ß-Carboline alkaloids from the roots of Peganum harmala L.

This study reports the isolation of four new ß-carboline alkaloids (1-4) and six previously identified alkaloids (5-10) from the roots of Peganum harmala L. Among these compounds, 1 and 2 were characterized as rare ß-carboline-quinazoline dimers exhibiting axial chirality. Compound 3 possessed a unique 6/5/6/7 tetracyclic ring system with an azepine ring, and compound 4 was a novel annomontine ß-carboline. The structures of these compounds were elucidated by spectroscopic data and quantum mechanical calculations. The biosynthetic pathways of 1-3 were proposed. Additionally, the cytotoxicity of some isolates against four cancer cell lines (HL-60, A549, MDA-MB-231, and DU145) was evaluated. Notably, compound 4 exhibited significant cytotoxicity against HL-60, A549, and DU145 cells with IC50 values of 12.39, 12.80, and 30.65 µmol·L-1, respectively. Furthermore, compound 2 demonstrated selective cytotoxicity against HL-60 cells with an IC50 value of 17.32 µmol·L-1.

Expanded Application of Piper nigrum: Guided Isolation of Alkaloids with Inhibitory Activities of AChE/BuChE and Aß Aggregation.

Piper nigrum is a popular crop that can be used as seasoning or as an additive but its active ingredients also have an effect on the nervous system. Nineteen new amide alkaloids (1a/1b, 2-5, 6a/6b, 7, 8a/8b, 9, 10a/10b, 11a-11b, 12-14) were isolated from P. nigrum, guided by inhibitory activity of AChE and LC-MS/MS based on GNPS. The configurations were determined by extensive spectral analysis, Bulkiness rule, and NMR calculations. The inhibitory activities of AChE/BuChE and Aß aggregation were tested, and the results showed compounds 2, 7, and 12 had significant inhibitory activities. These components were identified in the crude fraction and their relative quantities were tested, which suggested that compound 2 was the index component in the active site from P. nigrum.

Six undescribed guaianolide-type sesquiterpenes from the aerial parts of Daphne penicillata.

Six undescribed guaianolide sesquiterpenes (1-6) were obtained from the aerial parts of Daphne penicillata. Their structures and absolute configuration were elucidated by HRESIMS, NMR analyses, ECD calculations and single-crystal X-ray diffraction analysis. Structurally, all compounds possess the typical 5,7-fused system of 8,12-guaianolides and this guaianolide-type was first reported to be isolated from Daphne penicillata. All compounds (1-6) were evaluated for anti-inflammatory and cytotoxic activity. Among them, compounds 1 and 5 showed moderate inhibitory effects on LPS-induced NO production in BV2 cells and 4 displayed potential inhibition against Hep3B cells with an IC50 value of 7.33 µM.

Glucose-responsive enzymatic biomimetic nanodots for H2O2 self-supplied catalytic photothermal/chemodynamic anticancer therapy.

Photothermal therapy (PTT) combined with chemodynamic therapy (CDT) presents an appealing complementary anti-tumor strategy, wherein PTT accelerates the production of reactive oxygen species (ROS) in CDT and CDT eliminates residual tumor tissues that survive from PTT treatment. However, nanomaterials utilized in PTT/CDT are limited by non-specific damage to the entire organism. Herein, a glucose-responsive enzymatic Fe@HRP-ABTS/GOx nanodot is judiciously designed for tumor-specific PTT/CDT via a simple and clean protein-templated biomimetic mineralization synthesis. By oxidizing glucose in tumor cells, glucose oxidase (GOx) activates glucose-responsive tumor therapy and increases the concentration of H2O2 at the tumor site. More importantly, the self-supplied peroxide hydrogen (H2O2) can convert ABTS (2,2'-Hydrazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diamine salt) into oxidized ABTS (oxABTS) through horseradish peroxidase (HRP) catalysis for PTT and photoacoustic (PA) imaging. Furthermore, the Fe2+ arising from the reduction of Fe3+ by overexpressed GSH reacts with H2O2 to generate intensely reactive •OH through the Fenton reaction, concurrently depleting GSH and inducing efficient tumor CDT. The in vitro and in vivo experiments demonstrate superior cancer cell killing and tumor eradication effect of Fe@HRP-ABTS/GOx nanodot under near-infrared (NIR) laser irradiation. Collectively, the nanodots provide mutually reinforcing catalytic PTT/CDT anti-tumor strategies for treating liver cancer and potentially other malignancies. STATEMENT OF SIGNIFICANCE: Combinatorial antitumor therapy with nanomedicines presents great prospects for development. However, the limitation of non-specific damage to normal tissues hinders its further clinical application. In this work, we fabricated tumor-selective biomimetic Fe@HRP-ABTS/GOx nanodots for H2O2 self-supplied catalytic photothermal/chemodynamic therapy of tumors. The biomimetic synthesis strategy provides the nanodots with enzymatic activity in response to glucose to produce H2O2. The self-supplied H2O2 initiates photothermal therapy with oxidized ABTS and enhances chemodynamic therapy through simultaneous •OH generation and GSH depletion. Our work provides a new paradigm for developing tumor-selective catalytic nanomedicines and will guide further clinical translation of the enzymatic biomimetic synthesis strategy.

Stereochemical insights into structurally diverse lignanamides from the herbs of Solanum lyratum Thunb.

A chemical investigation of Solanum lyratum Thunb. (Solanaceae) afforded six pairs of enantiomeric lignanamides consisting of twelve undescribed compounds, along with two undescribed racemic mixtures, and the separations of the enantiomers were accomplished by chiral-phase HPLC. The structures of these undescribed compounds were elucidated by the analysis of spectroscopic data, NMR and electronic circular dichroism calculations. All isolated compounds were assessed for neuroprotective activities in H2O2-induced human neuroblastoma SH-SY5Y cells, and acetylcholinesterase (AChE) inhibitory activities. Among tested isolates, some enantiomeric lignanamides exhibited conspicuous neuroprotective effects and AChE inhibitory effect.

Four Pairs of Neuroprotective Aryldihydronaphthalene-Type Lignanamide Enantiomers from the Herbs of Solanum lyratum.

Four pairs of aryldihydronaphthalene-type lignanamide enantiomers were isolated from Solanum lyratum (Solanaceae). The enantiomeric separation was accomplished by chiral-phase HPLC, and five undescribed compounds were elucidated. Analysis by various spectroscopy and ECD calculations, the structures of undescribed compounds were illuminated. The neuroprotective effects of all compounds were evaluated using H2 O2 -induced human neuroblastoma SH-SY5Y cells and AchE inhibition activity. Among them, compound 4 a exhibited remarkable neuroprotective effects at high concentrations of 25 and 50 µmol/L comparable to Trolox. Compound 1 a showed the highest AchE inhibition with the IC50 value of 3.06±2.40 µmol/L. Molecular docking of the three active compounds was performed and the linkage between the compounds and the active site of AchE was elucidated.

Antimalarial and neuroprotective ent-abietane diterpenoids from the aerial parts of Phlogacanthus curviflorus.

Six new ent-abietane diterpenoids, abientaphlogatones A-F (1-6), along with two undescribed ent-abietane diterpenoid glucosides, abientaphlogasides A-B (7-8) and four known analogs were isolated from the aerial parts ofPhlogacanthus curviflorus (P. curviflorus). The structures of these compounds were determined using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), one-dimensional and two-dimensional nuclear magnetic resonance (NMR) spectroscopy, electronic circular dichroism (ECD) spectra, and quantum chemical calculations. Notably, compounds 5 and 6 represented the first reported instances of ent-norabietane diterpenoids from the genus Phlogacanthus. In the ß-hematin formation inhibition assay, compounds 2, 4, 7-10, and 12 displayed antimalarial activity, with IC50 values of 12.97-65.01 µmol·L-1. Furthermore, compounds 4, 5, 8, and 10 demonstrated neuroprotective activity in PC12 cell injury models induced by H2O2 and MPP+.

1H NMR-guided isolation of hasubanan alkaloids from the alkaloidal extract of Stephania longa.

1H NMR-guided fractionation led to the isolation of 16 alkaloids from the alkaloidal extract of Stephania longa, including 11 new hasubanan alkaloids (1-11) and five known alkaloids (12-16). Interestingly, compounds 2 and 11 are typically considered protonated tertiary amine compounds, whereas compounds 1 and 10 are regarded as oxidized versions of the corresponding compounds. Their gross structures were determined through an extensive analysis of spectroscopic data (NMR (nuclear magnetic resonance) and HRESIMS (high resolution electrospray ionization mass spectroscopy)), and their absolute configurations were established by comparing their experimental and calculated electronic circular dichroism (ECD) spectra. The new (3) and a known (12) compounds in all isolates displayed stronger antineuroinflammatory effects (IC50 values of 1.8 and 11.1 µM, respectively) than minocycline (IC50 value of 15.5 µM) against NO production on LPS-activated BV2 cells.

Potential inhibitors of microglial activation from the roots of Wikstroemia lichiangensis W. W. Sm.

Research on natural inhibitors of microglial overactivation derived from members of the Wikstroemia genus revealed that the extract of W. lichiangensis W. W. Sm. Has a remarkable inhibitory effect on nitric oxide production in overactivated microglia. In the present study, thirty-four compounds, including five undescribed sesquiterpenoids [wiksdauctins A-B (1-2) and wikscarotins A-C (3-5)] and one undescribed lignan [wikstroeminasin A (8)], were isolated from a 95% EtOH extract of W. lichiangensis roots using bio-guided phytochemical research. The structures of the isolated compounds were elucidated using comprehensive spectroscopic analyses. Furthermore, their anti-neuroinflammatory effects were evaluated in lipopolysaccharide-stimulated BV-2 microglia. Seventeen isolated compounds exhibited stronger inhibitory effects than positive control minocycline (IC50 values of 67.08 ± 1.95 µM), with IC50 values ranging from 7.35 ± 2.51 to 64.49 ± 3.38 µM. The findings of this study imply that the isolated compounds might serve as potential therapeutic agents for neurodegenerative diseases.

Determination of 44 major components and chemical profiling of saccharide in Chinese medicinal formula Lanqin Oral Liquid.

INTRODUCTION: Lanqin Oral Liquid (LQL) is a traditional Chinese medicine preparation (TCMP) containing five herbal medicines and has been commonly used for the treatment of pharyngitis and hand-foot-and-mouth disease in clinic. The material basis of LQL has been reported in our previous study, but the contents of the major components and the features of saccharide in LQL are still unclear. OBJECTIVES: This study aimed to establish accurate and rapid methods for the quantification of the major components and profiling of saccharide in LQL. The quantitative results combined with similarity evaluation were applied to improve the quality control of LQL. METHODOLOGY: An ultra-high performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UPLC-QQQ-MS) method was utilised to determine 44 major components. Cosine similarity was used to evaluate the similarities among 20 batches of LQL based on the quantitative results of 44 major components. The physicochemical properties, structure, composition, and contents of saccharide in LQL were detected by a combination of chemical and instrumental analysis. RESULTS: A total of 44 compounds, including flavonoids, iridoid glycosides, alkaloids, and nucleosides, were accurately determined. The 20 batches of LQL were remarkably similar (> 0.95). In addition, d-glucose, galactose, d-glucuronic acid, arabinose, and d-mannose were detected in saccharide of LQL. The contents of saccharide in LQL were 13.52-21.09 mg/ml. CONCLUSIONS: The established methods can be applied for the comprehensive quality control of LQL, including characterisation of saccharide and quantification of representative components. Our study will provide a robust chemical foundation for disclosing the quality markers of its therapeutic effect.

Anthraquinone metabolites isolated from the rhizosphere soil Streptomyces of Panax notoginseng (Burk.) F. H. Chen target MMP2 to inhibit cancer cell migration.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax notoginseng (Burk.) F. H. Chen belongs to the Araliaceae family. It has been used by traditional Chinese people in Northeast Asia for centuries as an antidiabetic, antioxidant, antitumor agent, etc. Endophytic or rhizospheric microorganisms play key roles in plant defense mechanisms, and they are essential in the discovery of pharmaceuticals and valuable new secondary metabolites. In particular, endophytic or rhizospheric microorganisms of traditional medicinal plants. AIM OF THE STUDY: To discover valuable new secondary metabolites from rhizosphere soil Streptomyces sp. SYP-A7185 of P. notoginseng, and to explore potential bioactivities and targets of metabolites protrusive function. MATERIALS AND METHODS: The metabolites were obtained via column chromatography and identified by multiple spectroscopic analyses. The antitumor, antioxidant, antibacterial, and antiglycosidases effects of isolated metabolites were tested using 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetazolium bromide (MTT), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 96-well turbidimetric, and α-glucosidase inhibitory assays. The potential antitumor targets were predicted through network pharmacological approaches. The interactions between metabolites and target were verified by molecular docking and biolayer interferometry (BLI) assay. The effects of cancer cells migration were detected through wound healing assays in A549 and MCF-7. Other cellular validation experiments including reverse transcription-quantitative PCR (RT‒qPCR) and western blotting (WB) were used to confirm the hypothesis of network pharmacology. RESULTS: Five different chemotypes of anthraquinone derivatives (1-10), including six new compounds (3, 6-10), were identified from Streptomyces sp. SYP-A7185. Compounds 1-6 and 9 displayed moderate to strong cytotoxicity on five human cancer cell lines (A549, HepG2, MCF-7, MDA-MD-231, and MGC-803). Moreover, matrix metalloproteinase-2 (MMP2) were predicted as a potential antitumor target of metabolites 1-6 and 9 by comprehensive network pharmacology analysis. Later, BLI assays revealed strong intermolecular interactions between MMP2 and antitumor metabolites, and molecular docking results showed the interaction of metabolites 1-6 and 9 with MMP2 was dependent on the crucial amino acid residues of LEU-83, ALA-84, LEU-117, HIS-131, PRO-135, GLY-136, ALA-140, PRO-141, TYR-143, and THR-144. These results implied that metabolites (1-6 and 9) might inhibit cancer cell migration besides cancer cell proliferation. After that, the cell wound healing assay showed that the cell migration processes were also inhibited after the treatments of compounds 1 and 3 in A549 and MCF-7 cells. In addition, the RT‒qPCR and WB results demonstrated that the gene expression levels of MMP2 were decreased after the treatment with compounds 1 and 3 in A549 and MCF-7 cells. Besides, compound 2 displayed moderate antioxidant activity (EC50, 27.43 µM), compounds 3 and 6 exhibited moderate antibacterial activity, and compound 3 inhibited α-glucosidase with an IC50 value of 13.10 µM. CONCLUSIONS: Anthraquinone metabolites, from rhizosphere soil Streptomyces sp. of P. notoginseng, possess antitumor, antioxidant, antibacterial, and antiglycosidase activities. Moreover, metabolites 1 and 3 inhibit cancer cells migration through downregulating MMP2.

HSQC-based small molecule accurate recognition technology discovery of diverse cytotoxic sesquiterpenoids from Elephantopus tomentosus L. and structural revision of molephantins A and B.

Elephantopus tomentosus L. is a perennial herb taxonomically belonging to the family Asteraceae, which has been used as a folk medicine for the treatment of hepatobiliary diseases. Sesquiterpenoids from this plant have broad biological activities, including anti-tumor, anti-inflammatory, and antibacterial effects. In this study, fifteen structurally diverse sesquiterpenoids comprised 11 germacrane-type and 4 eudesmane-type sesquiterpenoids were prioritized to isolated from Elephantopus tomentosus L. based on the HSQC-based Small Molecule Accurate Recognition Technology (SMART) strategy. Among them, ten sesquiterpenoids were previously unreported, and their structures were elucidated by spectroscopic data, computational methods, single-crystal X-ray diffraction crystallographic data or electronic circular dichroism calculations. In addition, the structures of two known sesquiterpenoids, molephantin A and B, which were reported to possess E-geometry for the Δ1(10) double bond, were revised by reanalyzing their spectroscopic and X-ray crystallographic data. Some sesquiterpenoids exhibited significant cytotoxic activities against Hep3B and HepG2 cell lines.

Two new iridoids and triterpenoid analogues from the leaves of Viburnum chingii and their anti-acetylcholinesterase activity.

Two undescribed split-ring iridoids (1-2) with six known triterpenes (3-8) and one steride (9) were isolated from the Viburnum chingii. Compound 2 possessed an unprecedented split-ring iridoid skeleton formed by electrocyclic reaction and split ring. The structures and absolute configurations of the new iridoids were established by NMR, HRESIMS, and ECD calculations. All the isolated compounds were tested for AChE inhibitory activity. Biologically, 1, 2, 3, 4, and 7 displayed significant AChE effects compared to the positive control donepezil, and have also been subjected to molecular docking studies.

Ciprofloxacin and pegylated G-CSF combined therapy mitigates brain hemorrhage and mortality induced by ionizing irradiation.

Introduction: Brain hemorrhage was found between 13 and 16 days after acute whole-body 9.5 Gy 60Co-γ irradiation (IR). This study tested countermeasures mitigating brain hemorrhage and increasing survival from IR. Previously, we found that pegylated G-CSF therapy (PEG) (i.e., Neulasta®, an FDA-approved drug) improved survival post-IR by 20-40%. This study investigated whether Ciprofloxacin (CIP) could enhance PEG-induced survival and whether IR-induced brain hemorrhage could be mitigated by PEG alone or combined with CIP. Methods: B6D2F1 female mice were exposed to 60Co-γ-radiation. CIP was fed to mice for 21 days. PEG was injected on days 1, 8, and 15. 30-day survival and weight loss were studied in mice treated with vehicles, CIP, PEG, or PEG + CIP. For the early time point study, blood and sternums on days 2, 4, 9, and 15 and brains on day 15 post-IR were collected. Platelet numbers, brain hemorrhage, and histopathology were analyzed. The cerebellum/pons/medulla oblongata were detected with glial fibrillary acidic protein (GFAP), p53, p16, interleukin-18 (IL-18), ICAM1, Claudin 2, ZO-1, and complement protein 3 (C3). Results: CIP + PEG enhanced survival after IR by 85% vs. the 30% improvement by PEG alone. IR depleted platelets, which was mitigated by PEG or CIP + PEG. Brain hemorrhage, both surface and intracranial, was observed, whereas the sham mice displayed no hemorrhage. CIP or CIP + PEG significantly mitigated brain hemorrhage. IR reduced GFAP levels that were recovered by CIP or CIP + PEG, but not by PEG alone. IR increased IL-18 levels on day 4 only, which was inhibited by CIP alone, PEG alone, or PEG + CIP. IR increased C3 on day 4 and day 15 and that coincided with the occurrence of brain hemorrhage on day 15. IR increased phosphorylated p53 and p53 levels, which was mitigated by CIP, PEG or PEG + CIP. P16, Claudin 2, and ZO-1 were not altered; ICAM1 was increased. Discussion: CIP + PEG enhanced survival post-IR more than PEG alone. The Concurrence of brain hemorrhage, C3 increases and p53 activation post-IR suggests their involvement in the IR-induced brain impairment. CIP + PEG effectively mitigated the brain lesions, suggesting effectiveness of CIP + PEG therapy for treating the IR-induced brain hemorrhage by recovering GFAP and platelets and reducing C3 and p53.

Solanoids F - I: Terpenoids from Solanum lyratum with neuroprotective effects against H2O2-induced SH-SY5Y cell injuries.

Four new terpenoids, solanoids F - I (1-4), together with eleven known compounds (5-15), were isolated from the whole herb of Solanum lyratum. The chemical structures were characterized by spectroscopic techniques, and electronic circular dichroism (ECD) data analysis was adopted to confirm the absolute configurations of 1-4. Compounds 1-6, 8 and 12-15 exhibited neuroprotective effects against H2O2-induced oxidative damage of human SH-SY5Y cells. Additionally, this study also combined Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses to explore the potential targets and signaling pathways of active terpenoids components in intervening Alzheimer's disease (AD).

Chemical constituents from Daphne giraldii and their cytotoxicities and inhibitory activities against acetylcholinesterase.

Seven triterpenoids (1-7), two prenylated coumarins (8 and 9), and one diphenylpropane (10), including five previously undescribed compounds (1-3, 8, and 10), were obtained from the stem and root barks of Daphne giraldii. The structures and absolute configurations of the new triterpenoids were established by NMR, HRESIMS, ECD calculations, and single-crystal X-ray diffraction analysis. All identified compounds were tested for cytotoxicities (human tumour cell line Hep3B) and inhibitory effects on AChE in vitro. Notably, prenylated coumarins (8 and 9) exhibited moderate cytotoxic activities and 3-hydroxy-substituted triterpenoids (2 and 4) showed mild inhibitory effects on AChE. Furthermore, compounds 2 and 4 have also been subjected to molecular docking studies to investigate the inhibitory mechanism.

Chemical structures and anti-tyrosinase activity of the constituents from Elephantopus scaber L.

Four undescribed compounds including one germacrane-type sesquiterpene lactones (1), alkaloid (2) along with two neolignans (3-4) were isolated from Elephantopus scaber L. Their structures and absolute configurations were elucidated unambiguously by means of 1D and 2D NMR spectroscopic data analysis, and quantum chemical electronic circular dichroism calculations, as well as single-crystal X-ray crystallography. Their anti-tyrosinase activities have been evaluated in vitro and compound 2 exhibited significant inhibitory activity. Furthermore, molecular docking was performed to study the interaction patterns between 2 and the tyrosinase.

Sesquiterpene coumarins isolated from Ferula bungeana and their anti-neuroinflammatory activities.

This is the first study to profile natural sesquiterpene coumarins (SCs) in Ferula bungeana, a medicinal plant of the genus Ferula in China. Eight undescribed sesquiterpene coumarins (1-8), along with six known ones (9-14) were obtained from the whole plant of F. bungeana. These unreported SCs (1-8) enriched the structural diversity of natural SCs, especially these with the hydroxy or carbonyl group at C-7' and a hydroperoxy group at C-7' or C-8'. Compounds (9-14) were reported for the first time from this plant. The in vitro anti-neuroinflammatory activity assay showed that compounds 2 and 9 showed stronger inhibitory effect on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglia, compared with positive control minocycline, and compounds 5 and 10 showed moderate inhibitory effects.

Acylated sucroses and butenolide analog from the leaves of Tripterygium wilfordii Hook. f. and their potential anti-tyrosinase effects.

Three undescribed acylated sucroses (1-3), one undescribed butenolide analog (4) along with three known compounds (5-7) were isolated from the aqueous EtOH extract of the dried leaves of Tripterygium wilfordii. Their structures were elucidated on the basis of spectroscopic analyses, electron circular dichroism (ECD) techniques, and saccharide hydrolysis. All the isolated compounds were tested for their anti-tyrosinase effects. Among them, 6 exhibited similar inhibitory effects on tyrosinase with IC50 values of 0.073 mM comparing to arbutin. Additionally, the possible mechanism of the interaction between 6 and the active site of tyrosinase was explored by molecular docking.

Anti-tumor alkaloids from Peganum harmala.

Six alkaloids peharmalines F-K, along with 14 known ones, were isolated from the aerial part of Peganum harmala L.. The structures of the isolated compounds were determined based on their HR-ESI-MS data, extensive NMR spectroscopic analyses, and ECD calculations. 3-(4-Hydroxyphenyl)quinoline exhibited potent antiproliferative activity against the HepG-2 cell lines with an IC50 value of 3.05 µM. Norharmane displayed a moderate inhibition against A549 and HepG-2 cells with IC50 values of 16.45 µM and 17.27 µM, respectively.