Six undescribed 23-norursane triterpenoids from the biotransformation of ilexgenin a by endophytic fungi and their vascular protective activity.

Biotransformation of ursane-type triterpenoid ilexgenin A by endophytic fungi Lasiodiplodia sp. MQD-4 and Pestalotiopsis sp. ZZ-1, isolated from Ilex pubescences and Callicarpa kwangtungensis respectively, was investigated for the first time. Six previously undescribed metabolites (1-6) with 23-norursane triterpenoids skeleton were isolated and their structures were unambiguously established by the analysis of spectroscopic data and single-crystal X-ray crystallographic experiments. Decarboxylation, oxidation, and hydroxylation reactions were observed on the triterpenoid skeleton. Especially, the decarboxylation of C-23 provided definite evidence to understand the biogenetic process of 23-norursane triterpenoids. Moreover, the qualitative analysis of the extract of I. pubescences showed metabolites 1, 3, 4, and 6 could be detected in the originated plant, indicating biotransformation by endophytic fungi is a practical strategy for the isolation of novel natural products. Finally, all isolates were evaluated for the protective activities against H2O2-induced HUVECs dysfunction in vitro. Compound 5 could improve the viability of endothelial cells and decrease the level of intracellular ROS.

Cytotoxic indole diterpenoids and rare pyridoxatin atropisomers from the endophytic fungus Tolypocladium sp. SHJJ1.

Phytochemical investigation on the extract of endophytic fungus Tolypocladium sp. SHJJ1 resulted in the identification of a pair of previously undescribed pyridoxatin atropisomers [1 (M/P)] and three new indole diterpenoids (3-5), together with a pair of known pyridoxatin atropisomers [2 (M/P)] and ten known indole diterpenoids (6-15). Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and X-ray diffraction. Among the undescribed natural products, [1 (M/P)] that two rapidly interconverting atropisomers are the third example to report in the pyridoxatin atropisomers. Except for compounds 1 (M/P) and 2 (M/P), all other compounds were tested for their cytotoxicity using HepG2, A549, and MCF-7 human cell lines. Compound 9 displayed moderate cytotoxicity against the HepG2, A549, and MCF-7 cell lines with IC50 values of 32.39 ± 1.48 µM, 26.06 ± 1.14 µM, and 31.44 ± 1.94 µM, respectively, which was similar to the positive drug cisplatin (with IC50 values of 32.55 ± 1.76 µM, 18.40 ± 1.43 µM, and 27.31 ± 1.22 µM, respectively).

Two new 2-(2-phenylethyl)chromone derivatives and two sesquiterpenes from agarwood of Aquilaria sinensis with anti-inflammatory activity.

Two new 2-(2-phenylethyl)chromones (1-2), two new sesquiterpenes (12-13), and twelve known compounds (3-11, 14-16) were isolated from agarwood of Aquilaria sinensis. These structures were confirmed by HRESIMS, 1D and 2D NMR spectra. The absolute configurations of two new sesquiterpenes were determined by comparing the experimental and calculated ECD spectra. Among them, 7,8-dihydroxy-2-[2-(4'-methoxyphenyl)ethyl]chromone (2) was the first time found that the hydroxyl groups at both C-7/C-8 in agarwood. And Aseudesm B (13), the aldehyded methyl group at C-5 of eucalyptane sesquiterpenes was first discovered in natural products. In the bioassays, all compounds were evaluated for their inhibitory activity against lipopolysaccharide-activated nitric oxide (NO) production in RAW264.7 cells. Compounds 2-5, 7, 9-10, and 13-14 revealed notable inhibitory effects against NO production with IC50 values ranging from 4.0 to 13.0 µM.

Decreased syntaxin17 expression contributes to the pathogenesis of acute pancreatitis in murine models by impairing autophagic degradation.

Acute pancreatitis (AP) is an inflammatory disease of the exocrine pancreas. Disruptions in organelle homeostasis, including macroautophagy/autophagy dysfunction and endoplasmic reticulum (ER) stress, have been implicated in human and rodent pancreatitis. Syntaxin 17 (STX17) belongs to the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) subfamily. The Qa-SNARE STX17 is an autophagosomal SNARE protein that interacts with SNAP29 (Qbc-SNARE) and the lysosomal SNARE VAMP8 (R-SNARE) to drive autophagosome-lysosome fusion. In this study, we investigated the role of STX17 in the pathogenesis of AP in male mice or rats induced by repeated intraperitoneal injections of cerulein. We showed that cerulein hyperstimulation induced AP in mouse and rat models, which was characterized by increased serum amylase and lipase activities, pancreatic edema, necrotic cell death and the infiltration of inflammatory cells, as well as markedly decreased pancreatic STX17 expression. A similar reduction in STX17 levels was observed in primary and AR42J pancreatic acinar cells treated with CCK (100 nM) in vitro. By analyzing autophagic flux, we found that the decrease in STX17 blocked autophagosome-lysosome fusion and autophagic degradation, as well as the activation of ER stress. Pancreas-specific STX17 knockdown using adenovirus-shSTX17 further exacerbated pancreatic edema, inflammatory cell infiltration and necrotic cell death after cerulein injection. These data demonstrate a critical role of STX17 in maintaining pancreatic homeostasis and provide new evidence that autophagy serves as a protective mechanism against AP.

Seven new meroterpenoids from the fungus Penicillium sclerotiorum GZU-XW03-2.

Seven previously undescribed meroterpenoids, peniscmeroterpenoids H - N (1-7), were isolated from the marine-derived fungus Penicillium sclerotiorum GZU-XW03-2. Their structures were established by the spectroscopic methods and the electronic circular dichroism (ECD) calculations. Peniscmeroterpenoid H was a 6/6/6/5/6 rearranged pentacyclic meroterpenoid, featuring a unique 2-oxaspiro[5.5] undeca-4,7-dien-3-one motif. Peniscmeroterpenoids I and J (2 and 3) owned rare 6(D)/5(E) fused rings were not common in natural products, and compound 2 was the second example of a berkeleyone analogue stripped of the methyl ester fragment. Peniscmeroterpenoid K (4) was the first case where the C-24 was oxidized. In bioassay, compound 5 showed moderate anti-inflammatory activity.

New chromone compounds from the marine derived fungus Diaporthe sp. XW12-1.

Four new chromone compounds diaporspchromanones A-C (1-3) and diaporspchromanone H (4), together with three known compounds (5-7) were separated from the marine derived fungus Diaporthe sp. XW12-1. The structures of the new compounds, including their absolute configurations, were elucidated by extensive spectroscopic analysis and the Mosher's ester method. Among them, diaporspchromanones A-C (1-3) possess a 3-substituted-chroman-4-one skeleton, which are rarely found in natural sources. In the bioassays, all compounds were evaluated for their inhibitory activity against lipopolysaccharide-activated nitric oxide (NO) production in RAW264.7 cells. Compounds 2 and 3 showed potent anti-inflammatory effects than the positive control (indomethacin, IC50, 70.33 ± 0.95 µM) (p < 0.05) with IC50 values of 19.06 ± 3.60 and 9.56 ± 0.18 µM, respectively.

Meroterpenoids from the fungus Penicillium sclerotiorum GZU-XW03-2 and their anti-inflammatory activity.

Seven undescribed meroterpenoids, peniscmeroterpenoids A - G, were isolated from the marine-derived fungus Penicillium sclerotiorum GZU-XW03-2. Their structures were established by the spectroscopic methods and the electronic circular dichroism (ECD) calculations. Peniscmeroterpenoid A possessed an unprecedented and highly oxidized 6/7/6/5/5 pentacyclic system, featuring a unique tetrahydrofuro [2,3-b]furan-2(3H)-one motif. Peniscmeroterpenoids B - E owned rare 6(D)/5(E) fused rings were not common in natural products, and peniscmeroterpenoid E is the first example of a berkeleyone analogue stripped of the methyl ester fragment. In bioassays, peniscmeroterpenoids A and D inhibited the production of nitric oxide (NO) in RAW264.7 cells with IC50 values of 26.60 ± 1.15 and 8.79 ± 1.22 µM. Moreover, peniscmeroterpenoid D significantly suppressed the production of pro-inflammatory mediators (COX-2, IL-1ß and IL-6) and the protein expression of the enzyme iNOS.

Bioactive pterocarpans from the root of Astragalus membranaceus var. mongholicus.

Eleven undescribed and three known pterocarpans were isolated and identified from the traditional Chinese medicine "Huang-qi", Astragali Radix (the root of Astragalus membranaceus var. mongholicus (Bunge) P.K.Hsiao). The structures of these pterocarpans were determined using spectroscopic, X-ray crystallographic, quantum chemical calculation, and chemical methods. Pterocarpans, almost exclusively distributed in the family of Leguminosae, are the second largest subgroup of isoflavanoids. However, pterocarpan glycoside number is limited, most of which are glucosides, and only one pterocarpan apioside was isolated from nature. Notably, nine rare apiosyl-containing pterocarpan glycosides were isolated and identified. The hypoglycemic activities of all these compounds were evaluated using α-glucosidase and DPP-IV inhibitory assays respectively, and some isolates displayed the α-glucosidase inhibitory function. The antioxidant activities of all compounds were evaluated using the ORAC and DPPH radical scavenging assays, respectively. All compounds exhibited varying degrees of oxygen radical absorbance capacity, and some compounds displayed DPPH radical scavenging ability.

Rare cytochalasans isolated from the mangrove endophytic fungus Xylaria arbuscula.

Four new cytochalasans, arbuschalasins A-D (1-4), along with thirteen known analogues (5-17), were isolated from the solid rice medium of endophytic fungus Xylaria arbuscula. Arbuschalasins A-B feature a rare 5/6/6/6 fused ring system while arbuschalasin D was characterized as the first example of natural cytochalasans that possesses a 5/5/11 fused scaffold. The structures of 1-4 were assigned by spectroscopic data, with their absolute structures being determined by electronic circular dichroism (ECD) calculations. All of the isolates were evaluated against the human colorectal adenocarcinoma cell lines (HCT15). Compounds 6 and 7 showed significant inhibitory effects (IC50 values were 13.5 and 13.4 µM, respectively), being more active than those of the positive control, fluorouracil (103.1 µM).

Two New Diterpenoids from Biscogniauxia sp. and Their Activities.

Two new diterpenoids, including a seco-isopimarane type (1) and an abietane type (2), were isolated from Biscogniauxia sp. (71-10-1-1). Their structures, including absolute configurations, were elucidated by NMR spectroscopic analyses, X-ray crystallography, 13C chemical shifts calculations, and ECD calculations. This is the first report of diterpenoids from Biscogniauxia sp. Furthermore, short-term memory enhancement against Alzheimer's disease (AD), anti-inflammatory, and cytotoxic activities of 1-2 were also evaluated. The results showed that compound 1 exhibited short-term memory enhancement activity against AD.

Butyrolactone and sesquiterpene derivatives as inhibitors of iNOS from the roots of Lindera glauca.

Nine previously undescribed butyrolactone and sesquiterpene derivatives, named cyclopentanone A (1), subamolides F and G (2 and 3), secosubamolide F (4), rupestonic acids J - L (5-7), linderaguaianols A and B (8 and 9), together with six known ones 10-15 were isolated from the roots of Lindera glauca. Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, quantum chemical calculations, and Mo2(AcO)4-induced circular dichroism. Compound 1 that possessed a unique five-membered cyclopentane skeleton with a side chain was rarely found from natural sources. The biogenetic pathway for 1-4 was postulated. Secosubamolide F (4) inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW264.7 cells with IC50 value of 1.73 ± 0.18 µM and also significantly suppressed the production of iNOS. The binding interactions between 4 and iNOS were investigated using docking analyses.

Caesalminaxins O-T, cassane diterpenoids from the seeds of Caesalpinia minax and their anti-inflammation.

Six previously undescribed cassane diterpenoids, named caesalminaxins O-T (1-6), together with 28 known compounds (7-34), were isolated from the seeds of Caesalpinia minax Hance. Their structures, including their absolute configurations were elucidated by extensive spectroscopic analysis, X-ray diffraction, and quantum chemical calculations. Among the undescribed diterpenoids, compound 6 that possessed an unusual enol group at C-7 with a highly deshielded 1H NMR signal was the first example in cassane diterpenoids. All of the isolates were evaluated for their inhibitory activity against lipopolysaccharide-activated NO production in RAW264.7 cells. Compound 16 showed moderate inhibitory activity with an IC50 value of 17.3 µM, which was more potent than the positive control (indomethacin, IC50 = 29.7 µM).

A facile and selective approach to the qualitative and quantitative analysis of triterpenoids and phenylpropanoids by UPLC/Q-TOF-MS/MS for the quality control of Ilex rotunda.

Ilex rotunda, in which triterpenoids and phenylpropanoids are major bioactive constituents, has been widely used in traditional Chinese medicines. In this study, a validated UPLC/Q-TOF-MS/MS method was developed to simultaneously identify and quantify the triterpenoids and phenylpropanoids in the stem bark, fruit, leaves, roots and stem xylem of this herbal medicine. A total of seventy triterpenoids and twelve phenylpropanoids were identified with the assistance of the modified mass defect filter and key product ion filter data processing strategies, and forty-eight of them were confirmed by reference substances. Meanwhile, the contents of twelve triterpenoids and three phenylpropanoids in the five plant parts were determined with good linearity (R2 ≥ 0.9993), precision (RSD ≤ 2.04%), repeatability (RSD ≤ 1.99%), stability (RSD ≤ 1.88%) and recovery (96.65-103.17% and RSD ≤ 3.54%). Furthermore, PCA and OPLS-DA methods were employed to visualize the relationships and discrimination of the forty-two stem bark samples from two origins based on the contents of fifteen analytes. Our findings may provide early scientific evidence for quality control and for elucidating the therapeutic principle of Ilex rotunda.

Simultaneous qualitative and quantitative evaluation of Ilex kudingcha C. J. tseng by using UPLC and UHPLC-qTOF-MS/MS.

In this study, a systematic method was established for the holistic quality control of Ilex kudingcha C. J. Tseng, a popular functional drink for adjuvant treatment of diabetes, hypertension, obesity and hyperlipidemia. Both qualitative and quantitative analyses were conducted. For qualitative analysis, an ultra high performance liquid chromatography (UHPLC) coupled with an electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-qTOF-MS) method was established for rapid separation and structural identification of the constituents in Ilex kudingcha. Samples were separated on an ACQUITY UPLC HSS T3C18 column (2.1 mm × 100 mm, 1.8 µm) by gradient elution using 0.1% (v/v) formic acid (solvent A) and acetonitrile (solvent B) as mobile phases at a flow rate of 0.25 mL min-1. The chromatographic profiling of Ilex kudingcha by UHPLC-qTOF-MS/MS resulted in the characterization of 53 compounds, comprising 18 compounds that were unambiguously identified by comparison with reference standards. For quantitative analysis, 18 major compounds from 15 batches of Ilex kudingcha samples were simultaneously detected by UPLC-DAD at wavelengths of 210 nm, 260 nm, and 326 nm. The method was validated with respect to precision, linearity, repeatability, stability, accuracy, and so on. The contents of the 18 target compounds were applied for hierarchical clustering analysis (HCA) and principal component analysis (PCA) to differentiate between the samples. The results of HCA and PCA were consistent with each other. Sample No. 1 differed significantly based on HCA and PCA, and the differentiating components were confirmed to originate from different batches of samples. Phenolic acids and triterpenes were found to be the main ingredients in Ilex kudingcha. This strategy was effective and straightforward, and provided a potential approach for holistic quality control of Ilex kudingcha.

[HPLC-UV fingerprints and chemical pattern recognition of Ilicis Pubescentis Radix].

The present study is to establish the fingerprints for the quality evaluation of Ilicis Pubescentis Radix by HPLC-UV. The chromatographic conditions were defined as Phenomenex Luna C18(4.6 mm × 250 mm, 5 µm). Mobile phase was acetonitrile-0.05% phosphoric acid in gradient elution, and the flow rate was 0.8 mL·min⁻¹.Column temperature was 30 °C and the injection volume was 10 µL．The detection wavelength was 210 nm. According to the similarity evaluation, the chemometric method was used to assess the quality of Ilicis Pubescentis Radix. The fingerprints of 16 batches of Ilicis Pubescentis Radix were established. There were 29 common peaks in the fingerprints and 12 common peaks were identified by reference substances. Fingerprints similarity of samples were greater than 0.92. The samples were classified into three groups by hierarchical cluster analysis combined with principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA), and seven components were the main markers that cause differences in the different batches of samples. By comparing the on-line UV spectra of chromatographic peaks, the chromatographic fingerprint was divided into three regions: region A showed seventeen main peaks (mainly lignans and phenolic acids); region B showed eight main peaks, which were proved as saponins; region C showed four main peaks, which were proved as other components. The established HPLC-UV fingerprint is highly specific, and can be used to evaluate the quality consistency of different batches of Ilicis Pubescentis Radix.

Triterpenoids with antiplatelet aggregation activity from Ilex rotunda.

Phytochemical studies on the barks of Ilex rotunda Thunb. had resulted in the isolation of seven previously undescribed triterpenoids, rotundinosides E-K, along with sixteen known ones. The structures of previously undescribed compounds were elucidated on the basis of extensive spectroscopic analysis and the sugar moieties were further identified by HPLC and GC after acid hydrolysis. Among the isolates, rotundinoside F featured a rare triterpene-phenylpropanoid hybrid structure and rotundinoside H was an uncommon triterpene saponin with α-linked glucopyranosyl moiety at C-3. The antiplatelet aggregation of all compounds were evaluated against ADP induced rat platelet aggregation in vitro, and five compounds exhibited moderate inhibitory effects with IC50 values ranging from 22.4 to 32.8 µM.

Bioactive glycosides from the roots of Ilex asprella.

Context The roots of Ilex asprella (Hook. et Arn.) Champ. ex Benth. (Aquifoliaceae) are widely used in Chinese medicine to treat influenza, amygdalitis, pertussis, etc. Their mechanism of action is still unknown, which raises the need to identify new bioactive compounds in this plant. Objective In this study, we isolated a novel saponin containing sulphonic groups, namely, asprellcoside A (1) and a known phenolic glycoside compound (2) from the roots of Ilex asprella and evaluated their bioactivities. Materials and methods Molecular structures were elucidated by analysing their spectral and chemical properties. The viability of A549 cells was tested using a MTT assay. Ability of the compounds to inhibit viruses was determined using the neuraminidase activity assay. Their anti-inflammatory effects were tested using the IP-10 activity assay using various concentrations (compound 1: 0.6, 0.2, 0.6, 1.70, 5.00 and 15.00 µM; compound 2: 0.4, 1.2, 3.6, 11.0, 33.0 and 100 µM). Their inhibitory effect on platelet aggregation induced by adenosine diphosphate (ADP) in rabbit plasma was determined at 60 and 80 µM. Results Both compounds inhibit influenza virus strain A/PuertoRico/8/1934 (H1N1) strongly with EC50 values of 4.1 and 1.7 µM, respectively. Both compounds inhibit the secretion of IP-10 with EC50 values of 6.6 and 2.5 µM, respectively. Compound 1 alone inhibited platelet aggregation significantly, with the rate of suppression being 47 ± 8 and 38 ± 3%, at 60 and 80 µM, respectively. Conclusions The results suggest that both compounds may be valid therapeutics against influenza virus infection and that compound 1 may be a novel agent for treating thrombosis.

Diterpenoid alkaloids and flavonoids from Delphinium trichophorum.

Five hetisane-type C20-diterpenoid alkaloids, trichodelphinines A-E, one delnudine-type C20-diterpenoid alkaloid, trichodelphinine F and three known flavonoids, quercetin, quercetin 3-O-ß-D-glucopyranoside, and quercetin 3-O-ß-D-glucopyranoside-7-O-α-L-arabinopyranoside, were isolated from whole plants of Delphinium trichophorum Franch. Their structures were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, (1)H-(1)H COSY, NOESY and X-ray crystallographic analysis, and from chemical evidence. The cytotoxic activities of the diterpenoid alkaloids were evaluated using the MTT method, and the IC50 values of their cytotoxicity against A549 cancer cells ranged from 12.03 to 52.79 µM.

[Tanshinone IIA protects against triptolide-induced liver injury via Nrf2/ARE activation].

The aim of this study is to investigate the protection effect of tanshinone IIA (Tan) against triptolide (TP)-induced liver injury and the mechanisms involved. Acute liver injury was induced by intraperitoneal injection of TP (1 mg x kg(-1)) in mice. The activities of AST, ALT and LDH in serum and the levels of GSH, GST, GSH-PX, SOD, CAT and MDA in liver tissue were detected. The histopathological changes of liver tissues were observed after HE staining. Nrf2 translocation in liver tissue was detected by Western blotting, and real-time PCR was used to measure the expression levels of GCLC, NQO1 and HO-1 mRNA. The results showed that pretreatment with Tan significantly prevented the TP induced liver injury as indicated by reducing the activities of AST, ALT and LDH (P < 0.01). Tan pretreatment also prevented TP-induced oxidative stress in the mice liver by inhibiting MDA and restoring the levels of GSH, GST, SOD and CAT (P < 0.05). Parallel to these changes, pretreatment with Tan could attenuate histopathologic changes induced by TP. Furthermore, the results indicated that Tan pretreatment caused nuclear accumulation of Nrf2 as well as induction of mRNA expression of antioxidant response element (ARE)-driven genes such as GCLC, NQO1 and HO-1. These results indicated that Tan could protect against TP-induced acute liver injury via the activation of Nrf2/ARE pathway.

A new triterpenoid glycoside from the roots of Ilex asprella.

AIM: To study the chemical constituents of the roots of Ilex asprella Champ. ex Benth. METHODS: Compounds were isolated by silica gel, ODS, and Sephadex LH-20 column chromatography, and their structures were elucidated on the basis of physicochemical properties and spectroscopic analysis. RESULTS: Four triterpenoid glycosides were isolated and identified as (3ß)-19-hydroxy-28-oxours-12-en-3-yl ß-D-glucopyranosiduronic acid n-butyl ester (1), ilexasoside A (2), monepaloside F (3), and ilexoside A (4). CONCLUSION: Compound 1 is a new triterpenoid glycoside, and compounds 3 and 4 were isolated from this plant for the first time.