Novel lignans from Zanthoxylum nitidum and antiproliferation activity of sesaminone in osimertinib-resistant non-small cell lung cancer cells.

Seven previously undescribed tetrahydrofuran lignans with different configurations and unusual isopentenyl substitutions, nitidumlignans D-J (corresponding to compounds 1, 2, 4, 6, 7, 9 and 10), along with 14 known lignans, were isolated from Zanthoxylum nitidum. Notably, compound 4 is an uncommon naturally occurring furan-core lignan derived from tetrahydrofuran aromatization. The antiproliferation activity of the isolated compounds (1-21) was determined in various human cancer cell lines. The structure-activity study revealed that the steric positioning and chirality of the lignans exert important effects on their activity and selectivity. In particular, compound 3 (sesaminone) exhibited potent antiproliferative activity in cancer cells, including acquired osimertinib-resistant non-small-cell lung cancer (HCC827-osi) cells. Compound 3 also inhibited colony formation and induced the apoptotic death of HCC827-osi cells. The underlying molecular mechanisms revealed that 3 downregulated the activation of the c-Met/JAK1/STAT3 and PI3K/AKT/mTOR signaling pathways in the HCC827-osi cells. In addition, the combination of 3 and osimertinib exhibited synergistic effects on the antiproliferative activity against HCC827-osi cells. Overall, these findings inform the structure elucidation of novel lignans isolated from Z. nitidum, and sesaminone was identified as a potential compound for exerting antiproliferative effects on osimertinib-resistant lung cancer cells.

Structurally diverse isobutylamides from Zanthoxylum nitidum.

Five pairs of new racemic alkamides (1a/1b and 4a/4b-7a/7b) and two new achiral derivatives (2-3), as well as five known ones (8-12), were purified from the 95% EtOH extract of Zanthoxylum nitidum. Their structures were elucidated based on spectroscopic analyses (NMR and HR-ESI-MS), electronic circular dichroism (ECD) and NMR calculations. The enantiomeric separation was successfully achieved by chiral-phase HPLC-ECD measurements. Among all the isolates, compounds 2, 3, and 10 showed inhibitory effects against five human cancer cell lines, with IC50 values in range of 18.51-48.03 µM.

Undescribed isoquinolines from Zanthoxylum nitidum and their antiproliferative effects against human cancer cell lines.

Eleven previously undescribed alkaloids, including three pairs of enantiomers nitidumalkaloids A-C, a pair of scalemic mixtures nitidumalkaloid D and three optically pure or achiral alkaloids, nitidumalkaloids E-G, along with 20 known alkaloids, were isolated from an ethanolic extract of the whole Zanthoxylum nitidum (Roxb.) DC plant. The chemical structures of the alkaloids were elucidated using a combination of comprehensive nuclear magnetic resonance (NMR) and high-resolution electro-spray ionization mass spectrometry (HR-ESI-MS) analyses. The configuration of the stereogenic centers of all undescribed compounds was precisely established based on single-crystal X-ray diffraction and electronic circular dichroism (ECD) calculations. Racemic mixtures of nitidumalkaloids A-D were purified, and their enantiomers were analyzed via chiral-phase high-performance liquid chromatography with electrochemical detection measurements (HPLC-ECD). Twelve compounds exhibited significant antiproliferative activities against a panel of cancer cell lines. Further studies were designed to investigate the underlying molecular mechanism of (1'S, 6R)-nitidumalkaloid B, which was the most active antiproliferative agent against human cancer A549 cells. G2/M cell cycle arrest, induction of apoptosis, and suppression of the Wnt/ß-catenin signaling pathway were in part associated with the antiproliferative activity of (1'S, 6R)-nitidumalkaloid B. Moreover, (1'S, 6R)-nitidumalkaloid B inhibited cell migration by downregulating the epithelial-mesenchymal transition process in A549 cells. These data suggest that the antiproliferation activity of (1'S, 6R)-nitidumalkaloid B was correlated with the stereoselectivity of the stereoisomers, and (1'S, 6R)-nitidumalkaloid B was prioritized as a potential leading compound for the management of aggressive human non-small-cell lung cancer (NSCLC) from natural products.

Synthesis and biological evaluation of thiazolidine-2-thione derivatives as novel xanthine oxidase inhibitors.

Xanthine oxidase (XO) is a key enzyme in the generation and development of hyperuricemia. Thiazolidine-2-thione, a typical heterocyclic compound, have been widely used in the field of drug synthesis. In this study, a series of novel thiazolidine-2-thione derivatives were synthesized as XO inhibitors, and the XO inhibitory potencies of obtained compounds were evaluated by in vitro enzyme catalysis. The result shown that compound 6k behaved the strongest XO inhibitory activity with an IC50 value of 3.56 µmol/L, which was approximately 2.5-fold more potent than allopurinol. The structure-activity relationship revealed that the phenyl-sulfonamide group was indispensable for thiazolidine-2-thione derivatives to produce XO inhibitory activity. The enzyme inhibition kinetics analyses confirmed that compound 6k exerted a mixed-type XO inhibition. Additionally, the molecular docking results suggested that the 4-fluorophenyl-sulfonyl moiety could interact with Gly260 and Ile264 in the innermost part of the active pocket through 2 hydrogen bonds, while the thiazolidinethione moiety could form two hydrogen bonds with Glu263 and Ser347 in hydrophobic pockets. In summary, the results described above suggested that compound 6k could be a valuable lead compound for the treatment of hyperuricemia as a novel XO inhibitor.

Discovery of 2H-chromone-4-one based sulfonamide derivatives as potent retinoic acid receptor-related orphan receptor γt inverse agonists.

Retinoic acid receptor related orphan receptor γt (RORγt), identified as the essential functional regulator of IL-17 producing Th17 cells, is an attractive drug target for treating autoimmune diseases. Starting from the reported GSK2981278 (Phase II), we structurally modified and synthesized a series of 2H-chromone-4-one based sulfonamide derivatives as novel RORγt inverse agonists, which significantly improved their human metabolic stabilities while maintaining a potent RORγt inverse agonist profile. Efforts in reducing the lipophilicity and improving the LLE values led to the discovery of c9, which demonstrated potent RORγt inverse agonistic activity and consistent metabolic stability. During in vivo studies, oral administration of compound c9 exhibited a robust and dose-dependent inhibition of IL-17A cytokine expression and significantly lessened the skin inflammatory symptoms in the mouse imiquimod-induced skin inflammation model. Docking analysis of the binding mode revealed that c9 can suitably occupy the active pocket, and the introduction of the morpholine pyridine group can interact with Leu396, His479, and Cys393. Thus, compound c9 was selected as a preclinical compound for treating Th17-driven autoimmune diseases.

Two new alkaloids from Tibetan medicine of Hypecoum leptocarpum.

Two new alkaloids, leptocarpinine B (1) and corydamine acid (2), with thirteen known alkaloid compounds (3-15), were isolated from Hypecoum leptocarpum. The structures of the isolated compounds were determined based on spectroscopic data analyses, including IR, ESI-MS, 1 D, and 2 D NMR. In addition, all the isolates were evaluated for cytotoxic activities. Compound 6 showed moderate cytotoxicity against human ovarian cancer cell lines (A2780), human cervical cancer cell lines (HeLa), and human hepatocellular carcinomas cell lines (HepG2).[Formula: see text].

Discovery of N-(2-benzyl-4-oxochroman-7-yl)-2-(5-(ethylsulfonyl) pyridin-2-yl) acetamide (b12) as a potent, selective, and orally available novel retinoic acid receptor-related orphan receptor γt inverse agonist.

The nuclear receptor retinoic acid receptor-related orphan receptor γ (RORγ, NR1F3, or RORc) exists in two isoforms, with one isoform (RORγ or RORc1) widely expressed in a variety of tissues, and the expression of the second isoform (RORγt or RORc2) restricted to the thymus and cells of the immune system. RORγt is a key regulator of the development and functions of T-helper 17 (Th17) cells. Clinical proof-of-concept (PoC) with small molecule inverse agonists of RORγt has been achieved with VTP-43742 (Phase II) for the treatment of psoriasis, and pre-clinical PoC for this mechanism has also been established for the treatment of autoimmune diseases. A series of aryl sulfonyl derivatives as novel RORγt inverse agonists were designed and synthesized based on VTP-43742. We conducted structural modifications that improved the activity profile. In pharmacodynamic (PD) studies, oral administration of compound b12 showed robust and dose-dependent inhibition of IL-6 and IL-17A cytokine expression. The ability of compound b12 to reduce the levels of IL-6 and IL-17A in vivo after oral dosing in mice, and a corresponding reduction in skin inflammation further supports the potential of small molecule RORγt modulation as a therapeutic target for the treatment of inflammatory diseases.

Discovery of Chromane-6-Sulfonamide Derivative as a Potent, Selective, and Orally Available Novel Retinoic Acid Receptor-Related Orphan Receptor γt Inverse Agonist.

Interleukin-17 (IL-17) is a proinflammatory cytokine that plays a dominant role in inflammation, autoimmunity, and host defense. RORγt is a key transcription factor mediating T helper 17 (Th17) cell differentiation and IL-17 production, which is able to activate CD8+ T cells and elicit antitumor efficacy. A series of sulfonamide derivatives as novel RORγt inverse agonists were designed and synthesized. Using GSK2981278 (phase II) as a starting point, we engineered structural modifications that significantly improved the activity and pharmacokinetic profile. In animal studies, oral administration of compound d3 showed a robust and dose-dependent inhibition of the IL-17A cytokine expression in a mouse imiquimod-induced skin inflammation model. Docking analysis of the binding mode revealed that the compound d3 occupied the active pocket suitably. Thus, compound d3 was selected as a clinical compound for the treatment of Th17-driven autoimmune diseases.

The neurotrophic and antineuroinflammatory effects of phenylpropanoids from Zanthoxylum nitidum var. tomentosum (Rutaceae).

Three novel lignans (1, 5 and 6) and two novel quinic acids (16 and 17) along with 15 known phenylpropanoids were obtained from the ethanol extract of Zanthoxylum nitidum var. tomentosum (Rutaceae). Their structures were confirmed by comprehensive spectroscopic data (NMR and HRESIMS), and the absolute configurations of all novel compounds were elucidated based on electronic circular dichroism (ECD) spectroscopic data. The production of nitric oxide (NO) in BV-2 microglial cells induced through lipopolysaccharide (LPS) was used to evaluate in vitro anti-neuroinflammatory activity of compounds 1-20. Compound 2, 3, 7 and 16 showed excellent inhibition of LPS-induced NO production. The structure-activity relationships of the isolates were investigated. In addition, the mechanism of action of 2 was elucidated by RT-PCR and Western blotting analysis, which indicated that it reduced neuroinflammatory mainly through NLRP3/caspase1 signaling pathways in LPS-induced BV2 microglial cells.

Anti-proliferative effects of diterpenoids from Sagittaria trifolia L. tubers on colon cancer cells by targeting the NF-κB pathway.

A new labdane-type diterpenoid, ent-19-ol-13-epi-manoyl oxide,19-undecane ester, together with ten known diterpenes, were isolated from the ethanolic crude extract of the fresh tubers of Sagittaria trifolia L. The chemical structures of these compounds were determined by extensive 2-D NMR experiments and by comparison with the data reported in the literature. These compounds showed different inhibitory effects on various human cancer cells. Among these, compound 11 exhibited potential inhibition effects against human colon cancer cells. Moreover, flow cytometry demonstrated that compound 11 arrested the cell cycle at the G1 phase and induced cellular apoptosis, accompanied by mitochondrial membrane potential reduction. Mechanistic studies revealed that treatment with compound 11 inhibited IKKα/ß phosphorylation and IκBα phosphorylation, which subsequently caused the blockage of NF-κB p65 phosphorylation and nuclear translocation. Compound 11 also inhibited the expression of c-Myc, Cyclin D1, and Bcl-2, the downstream targets of NF-κB. Therefore, our findings provided insight into the anticancer components of Sagittaria trifolia L. tubers, which could facilitate their utilization as functional food ingredients.

Anti-inflammatory activity of isobutylamides from zanthoxylum nitidum var. tomentosum.

Inflammation is a very common and important basic pathological process. There is still a great need for the isolation of effective anti-inflammatory agents from plants. In this paper, five new isobutylamides, zanthoxylumamides E-I (1-5), and four known isobutylamides (6-9) were isolated from Zanthoxylum nitidum var. tomentosum (Rutaceae). Chiral resolution of seven racemic isobutylamides (1-4 and 6-8) was successfully performed, and the absolute configurations of two stereoisomers of 1-4 were validated by ECD and NMR. The obtained isobutylamides were evaluated in vitro anti-inflammatory activity with the lipopolysaccharide (LPS)-stimulated production of nitric oxide (NO) in murine macrophage RAW264.7 cells. Compound 8 exhibited significant inhibition of LPS-induced NO production. The underlying molecular mechanisms of the anti-inflammatory activity of 8 revealed that it suppressed the NO production through the modulation of myeloid differentiation factor 88 (MyD88) and interferon regulatory factor 3 (IRF3) signaling pathways.

Five 11α, 12α-epoxy pentacyclic triterpenoid saponins with antithrombus activities from Glechoma longituba.

The present study reports the phytochemical investigation of n-butanol-soluble extracts of Glechoma longituba. Five new oleanane-type triterpenoid saponins with an 11α, 12α-epoxy unit, named glechomanosides A - E, were isolated from the n-butanol soluble fraction of G. longituba. Their chemical structures were established using HRESIMS, IR, 1D NMR, and 2D NMR techniques. The compounds were all evaluated for their antithrombus activities by monitoring thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), and antiplatelet aggregation assays. These results suggest that G. longituba might be a candidate plant source of an interesting antithrombotic activity.

NF-κB inhibitory and cytotoxic activities of hexacyclic triterpene acid constituents from Glechoma longituba.

BACKGROUND: Non-Small-Cell Lung Cancer (NSCLC) is the most-frequent cause of cancer death, and novel chemotherapeutic drugs for treating NSCLC are urgently needed. 2α, 3α, 23-trihydroxy-13α, 27-cyclours-11-en-28-oic acid (euscaphic acid G) is a new hexacyclic triterpene acid isolated by our group from Glechoma longituba (Nakai) Kupr. However, the underlying mechanisms responsible for the anticancer effects of hexacyclic triterpene acid have not been elucidated. PURPOSE: In the present work, we evaluated growth inhibitory effect of the new isolated hexacyclic triterpene acid and explored the underlying molecular mechanisms. METHODS/STUDY DESIGNS: Herbs were extracted and constituents were purified by chromatographic separation, including silica gel, ODS, MCI, Sephadex LH-20 and preparative HPLC. The compound structures were elucidated by the use of UV, NMR and MS spectral data. The anticancer activity of euscaphic acid G was evaluated by MTT assay. Cell cycle, apoptosis, reactive oxygen species and mitochondrial membrane potential were determined by flow cytometry. To display the possible mechanism of euscaphic acid G on NCI-H460 cells, RT-PCR, immunofluorescence and Western blot analysis were carried out. RESULTS: A new hexacyclic triterpene acid, euscaphic acid G, together with fifteen known triterpenoids, was isolated from the aerial parts of G. longituba. Our results showed that euscaphic acid G exerted strong anti-proliferative activity against NCI-H460 cells in a concentration- and time-dependent manner. Flow cytometry demonstrated euscaphic acid G arrested the cell cycle at G1 phase, induced cellular apoptosis, accompanied by ROS generation and mitochondrial membrane potential reduction. Mechanistic studies revealed that euscaphic acid G treatment inhibited IKKα/ß phosphorylation and IκBα phosphorylation, which subsequently caused the blockage of NF-κB p65 phosphorylation and nuclear translocation. CONCLUSION: In conclusion, these results suggested that euscaphic acid G from G. longituba showed potential anticancer effects against lung cancer cells via inducing cell cycle arrest and apoptosis, at least partly, through NF-κB signaling pathways.

New inhibitors of matrix metalloproteinases 9 (MMP-9): Lignans from Selaginella moellendorffii.

Matrix metalloproteinase 9 (MMP-9) is one of the structurally related zinc-dependent endopeptidases families and provides a new target for cancer therapy owing to its pivotal role in metastatic tumors. In this paper, fourteen lignans, including three novel lignans, named selamoellenin B-D (1-3), and eleven known lignan derivatives (4-14) were isolated from the plant of Selaginella moellendorffii. Among them, compound 3 is optically active, which was enantiomerically seperated to afford a pair of enantiomers, (-)-3 and (+)-3. Their structures were elucidated by extensive spectroscopic analyses. Their cytotoxic activities were evaluated against four human cancer cell lines. Among them, five compounds (4, 5, 6, 11 and 13) exhibited great potent cytotoxicity and their structure-activity relationships were also discussed. All compounds except for 3 lignan analogues with low cytotoxicity were selected for further in vitro enzyme inhibition, surface plasmon resonance (SPR), and molecular docking assays based on the MMPs target. The results shown that, compound 11 have the best inhibitory effect and can be considered as a potential drug candidate targeting at MMP-9 for cancer therapy.

A pentacyclic triterpene derivative possessing polyhydroxyl ring A suppresses growth of HeLa cells by reactive oxygen species-dependent NF-κB pathway.

Pentacyclic triterpene derivatives possessing polyhydroxyl ring A exhibit many important pharmacological activities. (1ß, 2α, 3ß, 19ß, 23)-1,2,3,19,23-pentahydroxyolean-12-en-28-oic acid (5), a new bioactive phytochemical with tetra-hydroxyl ring A isolated from Euphorbia sieboldiana in our laboratory, showed potential inhibition effects against several cancer cells previously. This study was performed to investigate the underlying mechanisms of action for its antitumor activity. The results showed that compound 5 inhibited dose-/time-dependently cell growth with low toxicity to normal cells and induced apoptosis in cervical cancer cells. Also, compound 5 inhibited the growth and proliferation of HeLa cells and resulted in G1 phase arrest. Furthermore, exposure of cells to compound 5 caused inactivation of the TNF-α-TAK1-IKK-NF-κB axis and inhibition of TNF-α-stimulated NF-κB activity, followed by down-regulation of NF-κB target genes involved in cell apoptosis (Bcl-2) and in the cell cycle and growth (Cyclin D, c-Myc). Additionally, compound 5 significantly suppressed the migration of HeLa cells. In addition, exposure of HeLa cells to compound 5 decreased the activity of NF-κB through the generation of reactive oxygen species (ROS). Collectively, these results suggested that compound 5 exerted potent anticancer effects on HeLa cells in vitro through targeting the ROS-dependent NF-κB signaling cascade and this compound may be a promising anticancer agent for cancer treatment.

Lung cancer and matrix metalloproteinases inhibitors of polyphenols from Selaginella tamariscina with suppression activity of migration.

Cancer metastasis has been a major impediment to effective cancer treatment and is the major cause of cancer-related death. Polyphenols compounds have been reported to possess anti-metastasis activity through their inhibitory activity of matrix metalloproteinases (MMPs). In this paper, twelve polyphenols compounds, including three novel phenols, named selaphenins A-C (1-3), two known selaginellin derivatives (4 and 5), together with seven known biflavonoids (6-12) were isolated from the plant of Selaginella tamariscina. Their structures were elucidated by extensive spectroscopic analyses. Notably, polyphenols compound 10 suppressed the migration of A549 cells by primary targeting MMP-9. The antitumor activity of compound 10 was possibly due to the induction of cell apoptosis through intrinsic apoptosis pathways, accompanied by increasing the expression of Bax and caspase-3 in a dose-dependent manner. This study provides evidence that polyphenols analogues from S. tamariscina as inhibitors of MMP-9 exhibited potential migration inhibition activities.

Selagintamarlin A: A Selaginellin Analogue Possessing a 1H-2-Benzopyran Core from Selaginella tamariscina.

Selagintamarlin A (1), a novel selaginellin analogue featuring the unique motif of 1H-2-benzopyran, a new selaginpulvilin E (2), together with eight known analogues were isolated from Selaginella tamariscina. Their structures were elucidated by extensive spectroscopic analyses. A plausible biosynthetic pathway of 1 was also postulated. Compound 1 showed remarkable inhibitory activity against phosphodiesterase-4 (PDE4D2), with an IC50 value of 40 nM, which is 20-fold higher than that of the positive control (rolipram). Furthermore, compound 1 significantly inhibited tubulin polymerization.