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.

Inula japonica ameliorated bleomycin-induced pulmonary fibrosis via inhibiting soluble epoxide hydrolase.

Pulmonary fibrosis is a progressive, irreversible, and fatal fibrotic lung disease with a high mortality and morbidity, and commonly nonresponsive to conventional therapy. Inula japonica Thunb. is a traditional Chinese medicine, known as "Xuan Fu Hua" in Chinese, and has been widely applied to relieve cough and dyspnea and eliminate retained phlegm with a long history. In this study, we aimed to evaluate the anti-fibrosis effect and action mechanism of I. japonica extract (IJE) for the treatment of bleomycin (BLM)-induced pulmonary fibrosis in mice. IJE treatment significantly restored BLM-induced alterations in body weight loss and lung function decline, decreased the collagen deposition induced by BLM in lung tissues, and inhibited fibrotic and inflammatory factors, such as α-SMA, TGF-ß1, TNF-α, IL-6, COX-2, NF-κB, and GSK3ß, in a dose-dependent manner. We found that IJE could enhance the concentration of 8,9-epoxyeicosatrienoic acid (8,9-EET) and decrease concentrations of 8,9-dihydroxyeicosatrienoic acid (8,9-DHET), 11,12-DHET, and 14,15-DHET in BLM-induced mice. Meanwhile, IJE suppressed protein and mRNA expression levels of soluble epoxide hydrolase (sEH), and significantly displayed the inhibition of sEH activity with an IC50 value of 0.98 µg/mL. Our results indicated that IJE exerted remarkable anti-fibrosis effect on BLM-induced pulmonary fibrosis in mice via inhibiting sEH activity, resulting in the regulation of GSK3ß signaling pathway. Our findings revealed the underlying action mechanism of I. japonica, and suggested that I. japonica could be regarded as a candidate resource for the treatment of pulmonary fibrosis.

Uncarialins A-I, Monoterpenoid Indole Alkaloids from Uncaria rhynchophylla as Natural Agonists of the 5-HT1A Receptor.

Nine new monoterpenoid indole alkaloids, uncarialins A-I (1-9), were isolated from Uncaria rhynchophylla as well as 14 known analogues (10-23). Their structures were determined by HRESIMS, 1D and 2D NMR, and experimental and calculated electronic circular dichroism data. Compounds 5, 7, 15, and 22 displayed significant agonistic effects against the 5-HT1A receptor with EC50 values of 2.2 ± 0.1, 0.1 ± 0.1, 1.6 ± 0.3, and 2.0 ± 0.5 µM, respectively. The mechanisms of action of these four compounds with the 5-HT1A receptor were investigated by molecular docking, and the results suggested that amino acid residues Asp116, Thr196, Asn386, and Tyr390 played critical roles in the observed activity of the above-mentioned compounds.

Demethylbellidifolin isolated from Swertia bimaculate against human carboxylesterase 2: Kinetics and interaction mechanism merged with docking simulations.

In this study, forty-nine kinds of traditional Chinese medicines (TCMs) were evaluated for their inhibitory activities against human carboxylesterase 2 (HCE 2) using a human liver microsome (HLM) system. Swertia bimaculata showed significant inhibition on HCE 2 at 10 µg/mL among forty-nine kinds of TCMs. The extract of Swertia bimaculata was separated by preparative HPLC to afford demethylbellidifolin (1) identified by MS, 1H NMR, and 13C NMR spectra. Demethylbellidifolin (1) was assayed for its inhibitory HCE 2 effect by HCE 2-mediated DDAB hydrolysis, and its potential IC50 value was 3.12 ±â€¯0.64 µM. Demethylbellidifolin (1) was assigned as a mixed-type competitive inhibitor with the inhibiton constant Ki value of 6.87 µM by Lineweaver-Burk and slope plots. Living cell imaging was conducted to corroborate its inhibitory HCE 2 activity. Molecular docking indicated potential interactions of demethylbellidifolin (1) with HCE 2 through two hydrogen bonds of the C-3 and C-5 hydroxy groups with amino acid residues Glu227 and Ser228 in the catalytic cavity, respectively.

Uncaria rhynchophylla Ameliorates Parkinson's Disease by Inhibiting HSP90 Expression: Insights from Quantitative Proteomics.

BACKGROUND/AIMS: Uncaria rhynchophylla, known as "Gou-teng", is a traditional Chinese medicine (TCM) used to extinguish wind, clear heat, arrest convulsions, and pacify the liver. Although U. rhynchophylla has a long history of being often used to treat central nervous system (CNS) diseases, its efficacy and potential mechanism are still uncertain. This study investigated neuroprotective effect and the underlying mechanism of U. rhynchophylla extract (URE) in MPP+-induced SH-SY5Y cells and MPTP-induced mice. METHODS: MPP+-induced SH-SY5Y cells and MPTP-induced mice were used to established Parkinson's disease (PD) models. Quantitative proteomics and bioinformatics were used to uncover proteomics changes of URE. Western blotting was used to validate main differentially expressed proteins and test HSP90 client proteins (apoptosis-related, autophagy-related, MAPKs, PI3K, and AKT proteins). Flow cytometry and JC-1 staining assay were further used to confirm the effect of URE on MPP+-induced apoptosis in SH-SY5Y cells. Gait analysis was used to detect the behavioral changes in MPTP-induced mice. The levels of dopamine (DA) and their metabolites were examined in striatum (STR) by HPLC-EC. The positive expression of tyrosine hydroxylase (TH) was detected by immunohischemical staining and Western blotting. RESULTS: URE dose-dependently increased the cell viability in MPP+-induced SH-SY5Y cells. Quantitative proteomics and bioinformatics results confirmed that HSP90 was an important differentially expressed protein of URE. URE inhibited the expression of HSP90, which further reversed MPP+-induced cell apoptosis and autophagy by increasing the expressions of Bcl-2, Cyclin D1, p-ERK, p-PI3K p85, PI3K p110α, p-AKT, and LC3-I and decreasing cleaved caspase 3, Bax, p-JNK, p-p38, and LC3-II. URE also markedly decreased the apoptotic ratio and elevated mitochondrial transmembrane potential (DΨm). Furthermore, URE treatment ameliorated behavioral impairments, increased the contents of DA and its metabolites and elevated the positive expressions of TH in SN and STR as well as the TH protein. CONCLUSIONS: URE possessed the neuroprotective effect in vivo and in vitro, regulated MAPK and PI3K-AKT signal pathways, and inhibited the expression of HSP90. U. rhynchophylla has potentials as therapeutic agent in PD treatment.

[Chemical Constituents of the Aerial Parts from Plumbago zeylanica].

Objective: To study the anti-oxidative constituents of the aerial parts of Plumbago zeylanica. Methods: The ethanol extract of Plumbago zeylanica was separated and purified by various chromatographic techniques. On the basis of various spectroscopic data, the structures of isolated compounds were elucidated. ABTS+radical scavenging were carried out in antioxidant activity evaluation of the isolated compounds. Results: Eleven compounds were isolated and identified as cis-isoshinanolone-4-O-ß-D-glucopyranoside( 1),tachioside( 2),2,6-dimethoxy-p-hydroquinone-1-O-ß-D-glucopyranoside( 3),3-( ß-D-glucopyranosyloxy)-4-methoxybenzoic acid( 4),3'-O-ß-D-glucopyranosyloxy-plumbagic acid( 5),3'-O-ß-D-glucopyranosyloxy-plumbagic acid methyl ester( 6),plumbagic acid( 7),plumbagine A( 8),plumbagine C( 9),syringate-4-O-ß-D-glucopyranoside( 10) and 2-methyl-5-hydroxychromone( 11). Compounds 2,3,and5 displayed significant scavenging effect on ABTS+. Conclusion: Compounds 1 ~ 4,10,11 are obtained from this plant for the first time. Compounds 2,3,and 5 show significant anti-oxidative effects.

Protostane Triterpenoids from the Rhizome of Alisma orientale Exhibit Inhibitory Effects on Human Carboxylesterase 2.

Twelve new and 10 known protostane triterpenoids were isolated from the rhizome of Alisma orientale. Their structures were elucidated based on physical data analyses, including UV, HRESIMS, NMR experiments ((1)H, (13)C NMR, (1)H-(1)H COSY, HSQC, HMBC, and NOESY), and induced electronic circular dichroism. New compounds 1-12 were classified as protostanes (1-10), 29-norprotostane (11), and 24-norprotostane (12) by structure analyses. Furthermore, the inhibitory effects on human carboxylesterases (hCE-1, hCE-2) of compounds 1-22 were evaluated. Compounds 2, 6, 9, and 11 showed moderate inhibitory activities and were selective toward hCE-2 enzymes, with IC50 values of 8.68, 4.72, 4.58, and 2.02 µM, respectively. The inhibition kinetics of compound 11 toward hCE-2 were established, and the Ki value was determined as 1.76 µM using a mixed inhibition model. The interaction of bioactive compound 11 with hCE-2 was shown using molecular docking.

Inhibitory Effects of Highly Oxygenated Lanostane Derivatives from the Fungus Ganoderma lucidum on P-Glycoprotein and α-Glucosidase.

Twelve new highly oxygenated lanostane triterpenoids and nine known ganoderic acids were isolated from the fruiting body of Ganoderma lucidum. The new compounds were lanostane nortriterpenoids with 27 carbons (1-5 and 8), lanostane nor-triterpenoids with 25 carbons (6 and 7), and lanostane triterpenoids (9-12) based on multiple spectroscopic data analysis, including HRESIMS, 1D-NMR, 2D-NMR, and CD. Compounds 1-5 were identified as rare nor-lanostanoids that contain a 17ß-pentatomic lactone ring. Compound 13, possessing a lactone ring, had been isolated previously. The P-glycoprotein (P-gp) inhibitory effects of compounds 1-21 were evaluated at a concentration of 20 µM using an adriamycin (ADM)-resistant human breast adenocarcinoma cell line (MCF-7/ADR). Compounds 1, 5, 18, and 20 and verapamil increased the accumulation of ADM in MCF-7/ADR cells approximately 3-fold when compared with the negative control. These data support the significant P-glycoprotein inhibitory activities of compounds 1, 5, 18, and 20. In silico docking analysis suggested these compounds had similar P-gp recognition mechanisms compared with those of verapamil (a classical inhibitor). Furthermore, in an in vitro bioassay, compounds 2, 4, 5, 6, and 18 showed moderate inhibitory effects against α-glucosidase compared with those of the positive control acarbose.

Phenolic constituents from the roots of Phyllodium pulchellum.

Three new phenolic constituents 1-3 were obtained from the 95% ethanol extract of the roots of Phyllodium pulchellum (Leguminosae). Their structures were elucidated on the basis of spectroscopic analyses, such as NMR, UV, IR, HR-ESI-MS, and CD. Furthermore, in an in vitro bioassay, all compounds were tested for inhibitory effects against the proliferation of acetaldehyde-stimulated HSC-T6 cells, and compound 3 exhibited potent inhibitory activity with the IC50 value of 7.6 µM.

[Chemical constituents against hepatic fibrosis from Phyllodium pulchellum roots].

OBJECTIVE: To investigate the bioactive constituents against hepatic fibrosis from the roots of Phyllodium pulchellum. METHODS: The chemical constituents of Phyllodium pulchellum roots were obtained by various chromatographic technologies and identified by several spectroscopic methods. RESULTS: Ten compounds were elucidated as 3,5,2',4'-tetrahydroxy-2",2"-dimethylpyrano-[5",6",7,8] -flavanone (1), yukovanol (2), citflavanone (3), 8-prenylated 5,7,3',4'-tetrahydroxyflavanone (4), pulchelstyrene A (5), pulchelstyrene B (6), pulchelstyrene D (7), 3-indolcarbaldehyde (8), 3-methoxyindole (9) and p-hydroxybenzoic acid (10). The effects to inhibit the proliferation of activated HSC-T6 cells of all isolated compounds were also evaluated. CONCLUSION: All compounds are isolated from this plant for the first time except for compounds 5 - 7. Compounds 2,4,5 and 6 can inhibit the proliferation of activated HSC-T6 cells in vitro.

Microbial transformation of deoxyandrographolide and their inhibitory activity on LPS-induced NO production in RAW 264.7 macrophages.

A series of analogues of deoxyandrographolide (1) transformed by Cunninghamella blakesleana AS 3.2004 were isolated and identified by spectral methods including 2D NMR. Among them, 3-oxo-17,19-dihydroxy-7,13-ent-labdadien-15,16-olide (9), 3-oxo-19-hydroxy-1,13-ent-labdadien-15,16-olide (16), 3-oxo-1ß-hydroxy-14-deoxy-andrographolide (17) and 3-oxo-2ß-hydroxy-14-deoxyandrographolide (18) are new compounds. And their structure-activity relationships (SAR) of inhibitory activity on LPS-induced NO production in RAW 264.7 macrophage cells were also discussed.

Microbial transformation of Norkurarinone by Cunninghamella blakesleana AS 3.970.

In this paper, microbial transformation of norkurarinone (1) by Cunninghamella blakesleana AS 3.970 was investigated and seven transformed products were isolated and characterized as kurarinone (2), 4″,5″-dihydroxykurarinone (3), 6″-hydroxyl-2'-methoxyl-norkurarinone 7-O-ß-d-glucoside (4), 6″-hydroxyl-norkurarinone 4'-O-ß-d-glucoside (5), 4″,5″-dihydroxynorkurarinone (6), 7-methoxyl-norkurarinone (7), and 7-methoxyl-4″,5″-dihydroxynorkurarinone (8), respectively. Among them, 3-5 are new compounds, and the glycosylation reaction in microbial transformation process was reported rarely. In addition, the cytotoxicities of transformed products (1-8) were also investigated.

Microbial biotransformation of kurarinone by Cunninghamella echinulata AS 3.3400.

In this paper, microbial transformation of kurarinone (1) by Cunninghamella echinulata AS 3.3400 was investigated and four transformed products were isolated and identified as 6″-hydroxykurarinone (2), 4″,5″,8″-trihydroxynorkurarinone (3), norkurarinone (4), and kurarinone-7-O-ß-glucoside (5), respectively. Among them, 3 and 5 are new compounds, and the rare glycosylation in microbial transformation was observed. In addition, the cytotoxicities of transformed products (2-5) were also investigated.

Human cytochrome P450 3A-mediated two-step oxidation metabolism of dimethomorph: Implications in the mechanism-based enzyme inactivation.

Dimethomorph (DMM), an effective and broad-spectrum fungicide applied in agriculture, is toxic to environments and living organisms due to the hazardous nature of its toxic residues. This study aims to investigate the human cytochrome P450 enzyme (CYP)-mediated oxidative metabolism of DMM by combining experimental and computational approaches. Dimethomorph was metabolized predominantly through a two-step oxidation process mediated by CYPs, and CYP3A was identified as the major contributor to DMM sequential oxidative metabolism. Meanwhile, DMM elicited the mechanism-based inactivation (MBI) of CYP3A in a suicide manner, and the iminium ion and epoxide reactive intermediates generated in DMM metabolism were identified as the culprits of MBI. Furthermore, three common pesticides, prochloraz (PCZ), difenoconazole (DFZ) and chlorothalonil (CTL), could significantly inhibit CYP3A-mediated DMM metabolism, and consequently trigger elevated exposure to DMM in vivo. Computational studies elucidated that the differentiation effects in charge distribution and the interaction pattern played crucial roles in DMM-induced MBI of CYP3A4 during sequential oxidative metabolism. Collectively, this study provided a global view of the two-step metabolic activation process of DMM mediated by CYP3A, which was beneficial for elucidating the environmental fate and toxicological mechanism of DMM in humans from a new perspective.

Biotransformation of 18ß-Glycyrrhetinic Acid by Human Intestinal Fungus Aspergillus niger RG13B1 and the Potential Anti-Inflammatory Mechanism of Its Metabolites.

18ß-Glycyrrhetinic acid (GA) is a triterpenoid possessing an anti-inflammatory activity in vivo, while the low bioavailability limits its application due to its intestinal accumulation. In order to investigate the metabolism of GA in intestinal microbes, it was incubated with human intestinal fungus Aspergillus niger RG13B1, finally leading to the isolation and identification of three new metabolites (1-3) and three known metabolites (4-6) based on 1D and 2D NMR and high-resolution electrospray ionization mass spectroscopy spectra. Metabolite 6 could target myeloid differentiation protein 2 (MD2) to suppress the activation of nuclear factor-kappa B (NF-κB) signaling pathway via inhibiting the nuclear translocation of p65 to downregulate its target proteins and genes in lipopolysaccharide (LPS)-mediated RAW264.7 cells. Molecular dynamics suggested that metabolite 6 interacted with MD2 through the hydrogen bond of amino acid residue Arg90. These findings demonstrated that metabolite 6 could serve as a potential candidate to develop the new inhibitors of MD2.

Metabolites isolated from the human intestinal fungus Penicillium oxalicum SL2 and their agonistic effects on PXR and FXR.

Intestinal commensal fungi are vital to human health, and their metabolites play a key role in the reciprocal relationship. In the present work, eighteen alkaloids and seven monoterpenoids were isolated from the fermentation of the human intestinal fungus Penicillium oxalicum SL2, including seven undescribed alkaloids (penicilloxalines A-G), three undescribed monoterpenoids (penicilloxalines H-J), and fifteen reported compounds. The structures of the isolated compounds were identified by HRESIMS, 1D and 2D NMR, electronic circular dichroism spectra and quantum chemical calculations. Some metabolites displayed moderate agonistic effects against the pregnane X receptor (PXR), whereas (6R)3,7-dimethyl-6,7-dihydroxy-2(Z)-octenoic acid displayed a significant agonistic effect against the farnesoid X receptor (FXR) with an EC50 value of 0.43 µM, which was verified by investigating FXR downstream target genes and proteins, such as small heterodimer partner 1 (SHP1), fibroblast growth factor (FGF), and bile salt export pump (BSEP).

Comparative metabolism of cinobufagin in liver microsomes from mouse, rat, dog, minipig, monkey, and human.

Cinobufagin (CB), a major bioactive component of the traditional Chinese medicine Chansu, has been reported to have potent antitumor activity. In this study, in vitro metabolism of CB among species was compared with respect to metabolic profiles, enzymes involved, and catalytic efficiency by using liver microsomes from human (HLM), mouse (MLM), rat (RLM), dog (DLM), minipig (PLM), and monkey (CyLM). Significant species differences in CB metabolism were revealed. In particular, species-specific deacetylation and epimerization combined with hydroxylation existed in RLM, whereas hydroxylation was a major pathway in HLM, MLM, DLM, PLM, and CyLM. Two monohydroxylated metabolites of CB in human and animal species were identified as 1α-hydroxylcinobufagin and 5ß-hydroxylcinobufagin by using liquid chromatography-mass spectrometry and two-dimensional NMR techniques. CYP3A4 was identified as the main isoform involved in CB hydroxylation in HLM on the basis of the chemical inhibition studies and screen assays with recombinant human cytochrome P450s. Furthermore, ketoconazole, a specific inhibitor of CYP3A, strongly inhibited CB hydroxylation in MLM, DLM, PLM, and CyLM, indicating that CYP3A was responsible for CB hydroxylation in these animal species. The apparent substrate affinity and catalytic efficiency for 1α- and 5ß-hydroxylation of CB in liver microsomes from various species were also determined. PLM appears to have K(m) and total intrinsic clearance value (V(max)/K(m)) similar to those for HLM, and the total microsomal intrinsic clearance values for CB obeyed the following order: mouse > dog > monkey > human > minipig. These findings provide vital information to better understand the metabolic behaviors of CB among various species.

Novel microbial transformation of resibufogenin by Fusarium solani.

In this paper, microbial transformation of resibufogenin by Fusarium solani AS 3.1829 was investigated, and five transformed products were isolated and identified as 3-ketone-resibufogenin (2), 3-one-cyclic 3-(1,2-dimethyl-1,2-ethanediylacetal)-resibufogenin (3), 3-dimethoxyl-resibufogenin (4), 3-epi-resibufogenin (5), and 3-epi-15α-hydroxy-7ßH-bufalin (6), respectively. Among them, 3, 4, and 6 are new compounds, and the rare double oxidization of C-3 was reported. In addition, the cytotoxicities of transformed products were also investigated.

Microbial transformation of deoxyandrographolide by Fusarium graminearum AS 3.4598.

Biotransformation of deoxyandrographolide (1) by Fusarium graminearum AS 3.4598 was investigated in this paper. And five transformed products of 1 by F. graminearum AS 3.4598 were obtained. Their chemical structures were characterized as 3-oxo-8α,17ß-epoxy-14-deoxyandrographolide (2), 3-oxo-14-deoxyandrographolide (3), 3-oxo-17,19-dihydroxyl-8,13-ent-labdadien-15,16-olide (4), 1ß-hydroxyl-14-deoxyandrographolide (5), and 7ß-hydroxyl-14-deoxyandrographolide (6) by spectral methods including 2D NMR. Among them, products 2, 4, and 5 are new.