Two Undescribed Protostane Triterpenoids from the Rhizome of Alisma plantago-aquatica.

Two undescribed protostane triterpenoids, 11-deoxy-13(17),15-dehydro-alisol B 23-acetate (2) and alisol S (3), together with 21 known ones (1, 4-23), were isolated from the dried rhizome of Alisma plantago-aquatica. Of these compounds, 13(17),15-Dehydro-alisol B 23-acetate (1) and 11-deoxy-13(17),15-dehydro-alisol B 23-acetate (2) are two protostane triterpenoids containing conjugated double bonds in the five-membered ring D that are rarely found from nature resource, while alisol S (3) is a protostane triterpenoid with undescribed tetrahydrofuran moiety linked via C20 -O-C24 at the side chain. Additionally, compound 18 is a new natural product, and cycloartenol triterpenoid 23 is a non protostane triterpenoid firstly isolated from genus Alisma. Their structures were elucidated by extensive spectral analysis of the UV, IR, MS, 1D and 2D NMR, and comparison of the experimental and calculated CD curves.

Study of Herbs Cortex Moutan, Poria cocos, and Alisma orientale and Periodontitis.

INTRODUCTION: The Chinese traditional herbs Cortex Moutan, Poria cocos, and Alisma orientale are considered to have potential to ameliorate periodontitis, although the possible underlying mechanisms remain mostly unknown. Due to the complex formulation of Chinese herbs, it is important to understand the mechanisms of pharmacologic effects of traditional herbs for better application in modern medical treatment. METHODS: Network pharmacology was applied to explore the mechanism of Cortex Moutan, Poria cocos, and Alisma orientale. First we analysed their chemical ingredients using the Traditional Chinese Medicine Systems Pharmacology database and identified 20 active ingredients. Then we analysed the target genes of these 20 active ingredients as well as genes associated with periodontitis and found 74 co-target genes. We further analysed the protein-protein interaction network of these 74 co-target genes using the STRING database and enriched the pathways using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. RESULTS: The top 10 core targets elicited were vascular endothelial growth factor A (VEGFA), interlukin-6 (IL-6), tumour necrosis factor (TNF), matrix metalloproteinase-2 (MMP2), matrix metalloproteinase-9 (MMP9), AKT serine/threonine kinase 1 (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), kinase insert domain receptor (KDR), fibroblast growth factor 2 (FGF2), and serpin family E member 1 (SERPINE1). Using these a network of "herbs-ingredients-targetgenes-KEGG pathways." was constructed. CONCLUSIONS: The target and bioprocess network suggested that the pharmacologic effects of Cortex Moutan, Poria cocos, and Alisma orientale may be mainly dependent on their anti-inflammatory potential. Further work is required to eucidate their detailed mechanisms of activity.

Alismol Purified from the Tuber of Alisma orientale Relieves Acute Lung Injury in Mice via Nrf2 Activation.

Since the ethanol extract of Alisma orientale Juzepzuk (EEAO) suppresses lung inflammation by suppressing Nuclear Factor-kappa B (NF-κB) and activating Nuclear Factor Erythroid 2-related Factor 2 (Nrf2), we set out to identify chemicals constituting EEAO that suppress lung inflammation. Here, we provide evidence that among the five most abundant chemical constituents identified by Ultra Performance Liquid Chromatography (UPLC) and Nuclear Magnetic Resonance (NMR), alismol is one of the candidate constituents that suppresses lung inflammation in a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model and protects mice from ALI-like symptoms. Alismol did not induce cytotoxicity or reactive oxygen species (ROS). When administered to the lung of LPS-induced ALI mice (n = 5/group), alismol decreased the level of neutrophils and of the pro-inflammatory molecules, including Tumor Necrosis Factor-alpha (TNF-α), Interleukin-1 beta (IL-1ß), Interleukin-6 (IL-6), Monocyte Chemoattractant Protein-1 (MCP-1), Interferon-gamma (IFN-γ), and Cyclooxygenase-2 (COX-2), suggesting an anti-inflammatory activity of alismol. Consistent with these findings, alismol ameliorated the key features of the inflamed lung of ALI, such as high cellularity due to infiltrated inflammatory cells, the development of hyaline membrane structure, and capillary destruction. Unlike EEAO, alismol did not suppress NF-κB activity but rather activated Nrf2. Consequently, alismol induced the expression of prototypic genes regulated by Nrf2, including Heme Oxygenase-1 (HO-1), NAD(P)H: quinine oxidoreductase-1 (NQO-1), and glutamyl cysteine ligase catalytic units (GCLC). Alismol activating Nrf2 appears to be associated with a decrease in the ubiquitination of Nrf2, a key suppressive mechanism for Nrf2 activity. Together, our results suggest that alismol is a chemical constituent of EEAO that contributes at least in part to suppressing some of the key features of ALI by activating Nrf2.

Translocation of TiO2 nanoparticles enhances phosphorus uptake by wetland plants: Evidence from Pistia stratiotes and Alisma plantago-aquatica.

Titanium dioxide nanoparticles (nTiO2) and phosphorus (P) are widely present in sewages. To verify the hypothesis and the associated mechanisms that root-to-shoot translocation of nTiO2 can enhance plant P uptake thus P removal during sewage treatment, two wetland plants (Pistia stratiotes and Alisma plantago-aquatica) with different lateral root structures were used to examine the effect of nTiO2 (89.7% anatase and 10.3% rutile) on plant growth and P uptake in a hydroponic system. Inductively coupled plasma-optical emission spectroscopy and transmission electron microscopy-energy dispersive spectroscopy showed that P. stratiotes with well-developed lateral roots translocated 1.4-16 fold higher nTiO2 than A. plantago-aquatica with poorly developed roots, indicating P. stratiotes is efficient in nTiO2 uptake. In addition, nTiO2 root-to-shoot translocation in P. stratiotes increased with increasing nTiO2 concentration, while the opposite occurred in A. plantago-aquatica. Corresponding to the stronger nTiO2 translocation in P. stratiotes, its P uptake efficiency (Imax) and P accumulation were greater than that in A. plantago-aquatica, with Imax being increased by 35.8% and -16.4% and shoot P concentrations being increased by 16.2-64.6% and 11.4%, respectively. The strong positive correlation between Ti and P concentrations in plant tissues (r = 0.72-0.89, P < 0.01) indicated that nTiO2 translocation enhanced P uptake. Moreover, nTiO2-enhanced P uptake promoted plant growth and photosynthetic pigment synthesis. Therefore, wetland plants with well-developed lateral roots like P. stratiotes have potential to be used in P removal from nTiO2-enriched sewages.

New Guaiane-Type Sesquiterpene and Norsesquiterpene from Alisma plantago-aquatica and Their Xanthine Oxidase Inhibitory Activity.

A new sesquiterpene (1) and a new norsesquiterpene (2) belonging guaiane-type skeleton together with six known compounds (3-8) were isolated from the rhizomes of Alisma plantago-aquatica. Their structures were determined by HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Absolute configurations of new compounds were established by experimental and TD-DFT computational ECD spectra. Compounds 1-8 exhibited xanthine oxidase inhibitory activity with their IC50 values in range of 9.4-66.7 µM. The sesquiterpenoids 1-5 displayed the inhibitory activity and hence they could be potential xanthine oxidase inhibitors from A. plantago-aquatica.

Phylogeny of Alisma (Alismataceae) revisited: implications for polyploid evolution and species delimitation.

Alisma L. is a genus of aquatic and wetland plants belonging to family Alismataceae. At present, it is thought to contain ten species. Variation in ploidy level is known in the genus, with diploids, tetraploids and hexaploids recorded. Previous molecular phylogenetic studies of Alisma have generated a robust backbone that reveals important aspects of the evolutionary history of this cosmopolitan genus, yet questions remain unresolved about the formation of the polyploid taxa and the taxonomy of one particularly challenging, widely distributed species complex. Here we directly sequenced, or cloned and sequenced, nuclear DNA (nrITS and phyA) and chloroplast DNA (matK, ndhF, psbA-trnH and rbcL) of multiple samples of six putative species and two varieties, and conducted molecular phylogenetic analyses. Alisma canaliculatum and its two varieties known in East Asia and A. rariflorum endemic to Japan possess closely related but heterogeneous genomes, strongly indicating that the two species were generated from two diploid progenitors, and are possibly siblings of one another. This evolutionary event may have occurred in Japan. Alisma canaliculatum var. canaliculatum is segregated into two types, each of which are geographically slightly differentiated in Japan. We reconstructed a single phylogeny based on the multi-locus data using Homologizer and then applied species delimitation analysis (STACEY). This allowed us to discern A. orientale as apparently endemic to the Southeast Asian Massif and distinct from the widespread A. plantago-aquatica. The former species was most likely formed through parapatric speciation at the southern edge of the distribution of the latter.

The combination of Alisma and Atractylodes ameliorates cerebral ischaemia/reperfusion injury by negatively regulating astrocyte-derived exosomal miR-200a-3p/141-3p by targeting SIRT1.

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Alisma and Atractylodes (AA), a classical traditional Chinese herbal decoction, may protect against cerebral ischaemia/reperfusion injury (CIRI). However, the underlying mechanism has not been characterized. Intriguingly, exosomal microRNAs (miRNAs) have been recognized as vital factors in the pharmacology of Chinese herbal decoctions. AIM OF THE STUDY: The aim of the present study was to assess whether the neuroprotective effect of AA was dependent on the efficient transfer of miRNAs via exosomes in the brain. MATERIALS AND METHODS: Bilateral common carotid artery ligation (BCAL) was used to induce transient global cerebral ischaemia/reperfusion (GCI/R) in C57BL/6 mice treated with/without AA. Neurological deficits were assessed with the modified neurological severity score (mNSS) and Morris water maze (MWM) test. Western blot (WB) analysis was used to detect the expression of sirtuin 1 (SIRT1) in the cerebral cortex. The inflammatory state was quantitatively evaluated by measuring the expression of phospho-Nuclear factor kappa B (p-NF-κB), Interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) using WB analysis and glial fibrillary acidic protein (GFAP) immunohistochemical staining. The protein expression of zonula occluden-1 (ZO-1), occludin, caudin-5 and CD31 was examined by immunohistochemical staining to determine blood‒brain barrier (BBB) permeability. Exosomes were extracted from the brain interstitial space by ultracentrifugation and identified by transmission electron microscopy (TEM), WB analysis and nanoparticle tracking analysis (NTA). The origin of exosomes was clarified by measuring the specific mRNAs within exosomes via Real Time Quantitative PCR (RT‒qPCR). Differential miRNAs in exosomes were identified using microarray screening and were validated by RT‒qPCR. Exosomes were labelled with fluorescent dye (PKH26) and incubated with bEnd.3 cells, the supernatant was collected, IL-1ß/TNF-α expression was measured using enzyme-linked immunosorbent assay (ELISA), total RNA was extracted, and miR-200a-3p/141-3p expression was examined by RT‒qPCR. In addition, the levels of miR-200a-3p/141-3p in oxygen glucose deprivation/reoxygenation (OGD/R)-induced bEnd.3 cells were quantified. The direct interaction between miR-200a-3p/141-3p and the SIRT1 3' untranslated region (3'UTR) was measured by determining SIRT1 expression in bEnd.3 cells transfected with the miR-200a-3p/141-3p mimic/inhibitor. RESULTS: Severe neurological deficits and memory loss caused by GCI/R in mice was markedly ameliorated by AA treatment, particularly in the AA medium-dose group. Moreover, AA-treated GCI/R-induced mice showed significant increases in SIRT1, ZO-1, occludin, caudin-5, and CD31 expression levels and decreases in p-NF-κB, IL-1ß, TNF-α, and GFAP expression levels compared with those in untreated GCI/R-induced mice. Furthermore, we found that miR-200a-3p/141-3p was enriched in astrocyte-derived exosomes from GCI/R-induced mice and could be inhibited by treatment with a medium dose of AA. The exosomes mediated the transfer of miR-200a-3p/141-3p into bEnd.3 cells, promoted IL-1ß and TNF-α release and downregulated the expression of SIRT1. No significant changes in the levels of miR-200a-3p/141-3p were observed in OGD/R-induced bEnd.3 cells. The miR-200a-3p/141-3p mimic/inhibitor decreased/increased SIRT1 expression in bEnd.3 cells, respectively. CONCLUSION: Our findings demonstrated that AA attenuated inflammation-mediated CIRI by inhibiting astrocyte-derived exosomal miR-200a-3p/141-3p by targeting the SIRT1 gene, which provided further evidence and identified a novel regulatory mechanism for the neuroprotective effects of AA.

Therapeutic Effects of Alisma orientale and its Active Constituents on Cardiovascular Disease and Obesity.

The treatment of cardiovascular diseases and obesity, two diseases posing a major risk to human health, has been plagued by the scarcity of potent and effective medication with fewer side effects. To address this problem, numerous efforts, and some progress, have been made. Among possible treatments are some medicinal herbs; particularly promising is Alisma orientale (AO). In the last decade, an increasing amount of research has shown that AO has some desirable therapeutic effects on cardiovascular diseases and obesity. Because of its efficacy, natural origin, and minimal adverse effects, AO has aroused great attention. Based on this, this review provides an overview of the latest progress from the last decade regarding the pharmacological and therapeutic effects, molecular mechanisms, and related effective constituents of AO in the treatment of cardiovascular diseases and obesity. Results from the research currently available reveal that active constituents of AO, such as alisol B 23-acetate, alisol A 24-acetace, and alisol A, have been proven to be effective for treating cardiovascular diseases by modulating the lipid metabolism of macrophages, improving the biological behavior of vascular smooth muscle cells (VSMCs), and enhancing anti-inflammatory effects. Moreover, the active constituents of AO can also intervene in obesity by modulating abnormal glucose and lipid metabolism and fat decomposition of the body by activating the AMPK- and PPAR-related signaling pathways. In summation, based upon our research of available literature, this review reveals that AO and its active constituents have a great potential to be used as drugs for treating cardiovascular diseases and ameliorating obesity.

PI3K/AKT/SERBP-1 pathway regulates Alisma orientalis beverage treatment of atherosclerosis in APOE-/- high-fat diet mice.

CONTEXT: Previously, we found Alisma orientalis beverage (AOB), a classic traditional Chinese medicine (TCM) formulation, had the potential effect of treating atherosclerosis (AS). The underlying mechanism was still unclear. OBJECTIVE: As an extention of our previous work, to investigate the underlying mechanism of action of AOB in the treatment for AS. MATERIALS AND METHODS: Network pharmacology was conducted using SwissTargetPrediction, GeneCards, DrugBank, Metascape, etc., to construct component-target-pathway networks. In vivo, AS models were induced by a high-fat diet (HFD) for 8 consecutive weeks in APOE-/- mice. After the administration of AOB (3.8 g/kg, i.g.) for 8 weeks, we assessed the aortic plaque, four indicators of blood lipids, and expression of the PI3K/AKT/SREBP-1 pathway in liver. RESULTS: Network pharmacology showed that PI3K/AKT/SREBP-1 played a role in AOB's treatment for AS (PI3K: degree = 18; AKT: degree = 17). Moreover, we found that the arterial plaque area and four indicators of blood lipids were all significantly reversed by AOB treatment in APOE-/- mice fed with HFD (plaque area reduced by about 37.75%). In addition, phosphorylated expression of PI3K/AKT and expression of SREBP-1 were obviously increased in APOE-/- mice fed with HFD, which were all improved by AOB (PI3K: 51.6%; AKT: 23.6%; SREBP-1: 40.0%). CONCLUSIONS: AOB had therapeutic effects for AS by improving blood lipids and inhibition of the PI3K/AKT/SERBP-1 pathway in the liver. This study provides new ideas for the treatment of AS, as well as new evidence for the clinical application of AOB.

Alisma Shugan Decoction attenuates hepatic fibrosis and endoplasmic reticulum stress in mice with carbon tetrachloride-induced fibrosis.

Background: Over the years, Alisma Shugan Decoction (ASD), because of its potent anti-inflammation activity, has been used in traditional Chinese medicine (TCM) for treatment of many inflammation-associated disorders including those of the heart, blood vessel and brain. Methods: Herein, we examined the probable therapeutic effect of ASD in carbon tetrachloride (CCl4)-induced liver injury and fibrosis mice models. Results: Our results demonstrate that ASD dose-dependently reduced the fibrosis-related increased collagen deposition secondary to liver tissue exposure to CCl4. Data from our biochemical analyses showed significantly less liver damage biomarkers including ALT, AST and hydroxyproline in the ASD-treated samples, suggesting hepato-protective effect of ASD. Furthermore, we demonstrated that treatment with ASD significantly reversed CCl4-induced elevation of TNF-α, IL-6, IL-1ß and MP-1. Interestingly, NF-κB signalling, a principal regulator of inflammation was markedly suppressed by ASD treatment. In addition, treatment with ASD deregulated stress signalling pathways by suppressing the expression of markers of unfolded protein response, such as ATF6, IRE and GRP78. Conclusion: In conclusion, the present study provides preclinical evidence for the use of ASD as an efficacious therapeutic option in cases of chemical-induced liver damage and/or fibrosis. Further large-cohort validation of these findings is warranted.

Flowering Biology of Alisma plantago-aquatica (Alismataceae).

Field observations of flowering Alisma plantago-aquatica plants were carried out in Moscow region (Russia). The A. plantago-aquatica flower remains anthetic for a single light day, from 9:00 a.m. to 8:00 p.m. White petals showed a contrast bicolored pattern in UV light, and the pattern probably serves as a nectar clue for pollinators. Flowers were visited by insects in daytime from 11:00 a.m. to 3:00 p.m. Coleopterans (Coccinellidae), dipterans (Drosophilidae, Hybotidae, Muscidae, Sepsidae, and Syrphidae), and hymenopterans (Apidae) were observed as flower visitors. Hoverflies (Syrphidae) and bees (Apidae) were the most frequent visitors. Large amounts of A. plantago-aquatica pollen grains were found on their bodies, and a major role in pollination was consequently assumed for the insects. Based on the original findings and literature data on A. plantago-aquatica reproductive biology in Belgium, Slovakia, and the Czech Republic, hoverflies were identified as the most stable and efficient pollinators of A. plantago-aquatica in various parts of the species range. Bees (Apidae) were recognized as A. plantago-aquatica pollinators for the first time in this work. A flower isolation experiment confirmed that A. plantago-aquatica is a self-compatible plant, but requires insects for the most efficient cross-pollination.

Screening of small molecule inhibitors against RhoA protein from Alisma using an online detection system.

Targeted high-throughput screening of inhibitors from natural products is an effective approach in the treatment of cancer progression. RhoA protein is essential for many signaling pathways. It is closely related to the occurrence and development of tumor. So far, there are only a few reports on the screening of small molecule inhibitors of RhoA protein from natural products. In this study, an online UHPLC-PDA-MS2-RhoA-FLD screening system was established for the first time to identify RhoA inhibitors from medicinal Alisma. Using this online system by adding fluorescent probes protopine [LZ1] to proteins, 17 active components were identified from Alisma, including 14 terpenoids. Their binding abilities were evaluated by Surface Plasmon Resonance experiments. The activities of representative compounds were tested and showed anti-proliferative effect in cancer cells. Mechanistic studies showed that these compounds were able to downregulate the cellular expressions of RhoA associated proteins. This study provides potential lead compounds as small molecule inhibitors of RhoA protein for cancer therapy. This reported method can be used for targeted screening of small molecule inhibitors against tumors, and provides an approach for screening tumor inhibitors from natural products.

Novel triterpenoids from Alisma plantago-aquatica with influence on LDL uptake in HepG2 cells by inhibiting PCSK9.

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9) has been regarded as an effective and exciting target in the treatment of atherosclerotic cardiovascular disease since 2003. Only two monoclonal antibodies have been approved in the market which, however, were also criticized for their high cost to $9000 per dose and delivery route. Exploration of natural new effective and cheaper small molecule alternatives with effective PCSK9 inhibition is feasible and desired. PURPOSE: The aim of the study was to explore natural small molecules with anti-hyperlipidemia activity through PCSK9 from Alisma plantago-aquatica. METHOD: A targeted isolation of triterpenoids from A. plantago-aquatica by LC-Orbitrap-QDa was conducted. The isolates were evaluated for their DiI-LDL uptake promoting activity with fluorescence intensity assayed in High-content Imaging System and PCSK9 inhibitory activity by Human PCSK9 Kit or western blot. The LDL uptake and PCSK9 level of target component in different concentrations and their mRNA level were further verified by corresponding kit, qPCR and western blot. RESULTS: Six novel triterpenoids, including three unusual nor-triterpenoids (1-3) and three protostane-type triterpenoids (4-6), along with thirty-four known ones, were isolated from A. plantago-aquatica. Compound 2 had the lowest number of carbon atoms than previous reported nor-PTs in this plant. The 17 triterpenoids showed relatively remarkable activities in promoting LDL uptake with relevant structure-activity relationships. And 6 triterpenoids may improve LDL uptake in HepG2 cells by inhibiting PCSK9, especially for alisol G (28) with PCSK9 inhibition reaching to 55.6%, which demonstrated to increase LDLR mRNA or protein, and simultaneously reduce PCSK9 mRNA or protein significantly. CONCLUSION: The protostane triterpenoids may serve as a new source for PCSK9 inhibitors.

Comparative analysis of the structure and function of rhizosphere microbiome of the Chinese medicinal herb Alisma in different regions.

Rhizoma Alismatis, a commonly used traditional Chinese medicine, is the dried tuber of Alisma orientale and Alisma A. plantago-aquatica, mainly cultivated in Fujian and Sichuan provinces (China), respectively. Studies have shown that the rhizosphere microbiome is a key factor determining quality of Chinese medicinal plants. Here we applied metagenomics to investigate the rhizosphere microbiome of Alisma in Fujian and Sichuan, focusing on its structure and function and those genes involved in protostane triterpenes biosynthesis. The dominant phyla were Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, and Gemmatimonadetes. Compared with Fujian, the rhizosphere of Sichuan has a greater α diversity and stronger microbial interactions but significantly lower relative abundance of archaea. Microbes with disease-suppressing functions were more abundant in Sichuan than Fujian, but vice versa for those with IAA-producing functions. Gemmatimonas, Anaeromyxobacter, and Pseudolabrys were the main contributors to the potential functional difference in two regions. Genes related to protostane triterpenes biosynthesis were enriched in Fujian. Steroidobacter, Pseudolabrys, Nevskia, and Nitrospira may contribute to the accumulation of protostane triterpenes in Alisma. This work fills a knowledge gap of Alisma's rhizosphere microbiome, providing a valuable reference for studying its beneficial microorganisms.

Beneficial Activities of Alisma orientale Extract in a Western Diet-Induced Murine Non-Alcoholic Steatohepatitis and Related Fibrosis Model via Regulation of the Hepatic Adiponectin and Farnesoid X Receptor Pathways.

The hepatic adiponectin and farnesoid X receptor (FXR) signaling pathways play multiple roles in modulating lipid and glucose metabolism, reducing hepatic inflammation and fibrosis, and altering various metabolic targets for the management of non-alcoholic fatty liver disease (NAFLD). Alisma orientale (AO, Ze xie in Chinese and Taeksa in Korean) is an herbal plant whose tubers are enriched with triterpenoids, which have been reported to exhibit various bioactive properties associated with NAFLD. Here, the present study provides a preclinical evaluation of the biological functions and related signaling pathways of AO extract for the treatment of NAFLD in a Western diet (WD)-induced mouse model. The findings showed that AO extract significantly reversed serum markers (liver function, lipid profile, and glucose) and improved histological features in the liver sections of mice fed WD for 52 weeks. In addition, it also reduced hepatic expression of fibrogenic markers in liver tissue and decreased the extent of collagen-positive areas, as well as inhibited F4/80 macrophage aggregation and inflammatory cytokine secretion. The activation of adiponectin and FXR expression in hepatic tissue may be a major mechanistic signaling cascade supporting the promising role of AO in NAFLD pharmacotherapy. Collectively, our results demonstrated that AO extract improves non-alcoholic steatohepatitis (NASH) resolution, particularly with respect to NASH-related fibrosis, along with the regulation of liver enzymes, postprandial hyperglycemia, hyperlipidemia, and weight loss, probably through the modulation of the hepatic adiponectin and FXR pathways.

Promising Anticancer Activities of Alismatis rhizome and Its Triterpenes via p38 and PI3K/Akt/mTOR Signaling Pathways.

The flowering plant genus Alisma, which belongs to the family Alismataceae, comprises 11 species, including Alisma orientale, Alisma canaliculatum, and Alisma plantago-aquatica. Alismatis rhizome (Ze xie in Chinese, Takusha in Japanese, and Taeksa in Korean, AR), the tubers of medicinal plants from Alisma species, have long been used to treat inflammatory diseases, hyperlipidemia, diabetes, bacterial infection, edema, oliguria, diarrhea, and dizziness. Recent evidence has demonstrated that its extract showed pharmacological activities to effectively reverse cancer-related molecular targets. In particular, triterpenes naturally isolated from AR have been found to exhibit antitumor activity. This study aimed to describe the biological activities and plausible signaling cascades of AR and its main compounds in experimental models representing cancer-related physiology and pathology. Available in vitro and in vivo studies revealed that AR extract possesses anticancer activity against various cancer cells, and the efficacy might be attributed to the cytotoxic and antimetastatic effects of its alisol compounds, such as alisol A, alisol B, and alisol B 23-acetate. Several beneficial functions of triterpenoids found in AR might be due to p38 activation and inhibition of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathways. Moreover, AR and its triterpenes inhibit the proliferation of cancer cells that are resistant to chemotherapy. Thus, AR and its triterpenes may play potential roles in tumor attack, as well as a therapeutic remedy alone and in combination with other chemotherapeutic drugs.

Proteomic insights into protostane triterpene biosynthesis regulatory mechanism after MeJA treatment in Alisma orientale (Sam.) Juz.

Protostane triterpenes in Alisma orientale (Sam.) Juz. have unique structural features with distinct pharmacological activities. Previously we have demonstrated that protostane triterpene biosynthesis could be regulated by methyl jasmonate (MeJA) induction in A. orientale. Here, proteomic investigation reveals the MeJA mediated regulation of protostane triterpene biosynthesis. In our study, 281 differentially abundant proteins were identified from MeJA-treated compared to control groups, while they were mainly associated with triterpene biosynthesis, α-linolenic acid metabolism, carbohydrate metabolism and response to stress/defense. Key enzymes 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), squalene epoxidase (SE), oxidosqualene cyclase (OSC) and cytochrome P450s which potentially involved in protostane triterpene biosynthesis were significantly enriched in MeJA-treated group. Basic Helix-loop-helix (bHLH), MYB, and GRAS transcription factors were enhanced after MeJA treatment, and they also improved the expressions of key enzymes in Mevalonate pathway and protostane triterpene. Then, MeJA also could increase the expression of α-galactosidase (α-GAL), thereby promoting carbohydrate decomposition, and providing energy and carbon skeletons for protostane triterpene precursor biosynthesis. As well, exogenous MeJA treatment upregulated 13-lipoxygenase (13-LOX), allene oxide synthase (AOS) and allene oxide cyclase (AOC) involved in α-linolenic acid metabolism, leading to the accumulation of endogenous MeJA and activation of the protostane triterpene biosynthesis transduction. Finally, MeJA upregulated stress/defence-related proteins, as to enhance the defence responses activity of plants. These results were further verified by quantitative real-time PCR analysis of 19 selected genes and content analysis of protostane triterpene. The results provide some new insights into the role of MeJA in protostane triterpene biosynthesis.

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, 3ß-hydroxy-25-anhydro-alisol F (1) and 3ß-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 Ki 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 canaliculatum Extract Affects AGS Gastric Cancer Cells by Inducing Apoptosis.

The anti-cancer effects of Alisma canaliculatum extracts (ACE) were identified in AGS gastric cancer cells. Our results showed that ACE inhibited the growth of AGS cells, increased the proportion of sub-G1 phase cells, and depolarized the membrane potential of mitochondria. ACE-induced gastric cancer cell death was associated with Bcl-2, survivin and Bax level changes, and it activated caspase-3 and -9. In addition, it was involved in the activation of MAPKs and increased the reactive oxygen species (ROS). These results suggest that ACE induces apoptosis in AGS gastric cancer cells, and therefore, ACE may have the potential to treat gastric cancer.

Alisol A 24-acetate stimulates lipolysis in 3 T3-L1 adipocytes.

BACKGROUND: Alisol A 24-acetate (AA-24-a), one of the main active triterpenes isolated from the well-known medicinal plant Alisma orientale (Sam.) Juz., exhibits multiple biological activities including hypolipidemic activity. However, its effect on lipid metabolism in adipocytes remains unclear. The present study aimed to clarify the effect of AA-24-a on adipocyte lipolysis and to determine its potential mechanism of action using 3 T3-L1 cells. METHODS: We assayed the release of glycerol into culture medium of 3 T3-L1 cells under treatment with AA-24-a. Protein and mRNA expression and phosphorylation levels of the main lipases and kinases involved in lipolysis regulation were determined by quantitative polymerase chain reaction and western blotting. Specific inhibitors of protein kinase A (PKA; H89) and extracellular signal-regulated kinase (ERK; PD98059), which are key enzymes in relevant signaling pathways, were used to examine their roles in AA-24-a-stimulated lipolysis. RESULTS: AA-24-a significantly stimulated neutral lipolysis in fully differentiated adipocytes. To determine the underlying mechanism, we assessed the changes in mRNA and protein levels of key lipolysis-related genes in the presence or absence of H89 and PD98059. Both inhibitors reduced AA-24-a-induced lipolysis. Moreover, pretreatment with H89 attenuated AA-24-a-induced phosphorylation of hormone-sensitive lipase at Ser660, while pretreatment with PD98059 attenuated AA-24-a-induced downregulation of peroxisome proliferator-activated receptor-γ and perilipin A. CONCLUSIONS: Our results indicate that AA-24-a promoted neutral lipolysis in 3 T3-L1 adipocytes by activating PKA-mediated phosphorylation of hormone-sensitive lipase and ERK- mediated downregulation of expression of perilipin A.