Potent anti-angiogenic component in Kaempferia galanga L. and its mechanism of action.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditionally, the roots of Kaempferia galanga has been used to treat high blood pressure, chest pain, headache, toothache, rheumatism, indigestion, cough, inflammation and cancer in Asia. Nevertheless, most of its pharmacological studies were focused on ethanolic extracts and volatile oils. The exact active chemical constituents and their underlying mechanisms are still poorly understood, especially towards its anti-cancer treatment. Inhibition of angiogenesis is an important atrategy to inhibit tumor growth. It has been reported that the low polar component of the plant possessed anti-angiogenic activity. Yet, the potent compound which is responsible for the effect and its molecular mechanism has not been reported. AIM OF THE STUDY: To determine the potent anti-angiogenic component in K.galanga and its mechanism of action. MATERIAL AND METHODS: The low polar components of the plant were concentrated using the methods of supercritical fluid extraction (SFE), subcritical extraction (SCE) and steam distillation (SD). The anti-angiogenic activity of the three extracts was evaluated using a zebrafish model. The content of the active compound in those extracts was determined with HPLC analysis. The in-vitro and in-vivo activity of the isolated compound was evaluated using human umbilical vein endothelial cells (HUVECs) model, the aortic ring assay and the matrigel plug assay, respectively. Its molecular mechanism was further studied by the western blotting assay and computer-docking experiments. Besides, its cytotoxicity on cancer and normal cell lines was evaluated using the cell-counting kit. RESULTS: HPLC results showed that trans-ethyl p-methoxycinnamate (TEM) was the major component of the extracts. The extract of SFE showed the best effect as it has the highest content of TEM. TEM could inhibit vascular endothelial growth factor (VEGF)-induced viability, migration, invasion and tube formation in human umbilical vein endothelial cells (HUVECs) in vitro. Moreover, it inhibited VEGF-induced sprout formation ex vivo and vessel formation in vivo. Mechanistic study showed that it could suppress tyrosine kinase activity of the receptor of VEGF (VEGFR2) and alter its downstream signaling pathways. In addition, the molecular docking showed that the binding of TEM and VEGFR2 is stable, which mainly attributed to the non-covalent binding interaction. Beside, TEM possessed little toxicity to both cancer and normal cells. CONCLUSION: TEM is the major anti-angiogenic component present in K. galanga and its anti-angiogenic property rather than toxicity provides scientific basis for the traditional use of K. galanga in cancer treatment.

Lysidrhodosides A-I, acylphloroglucinol glucosides with anti-inflammatory activities from the leaves of Lysidice rhodostegia.

Lysidrhodosides A-I (1-9), nine acylphloroglucinol glucoside derivatives along with three known analogues (10-12) were isolated from the leaves of Lysidice rhodostegia. Their structures and absolute configuration were elucidated by spectroscopic data analysis (NMR, UV, IR, HR-ESI-MS), single-crystal X-ray diffraction, and acid hydrolysis with HPLC analysis. Notably, compounds 7-9 represent the first examples of 3-methylbutyryl phloroglucinol glucoside dimers isolated from this plant. Additionally, compounds 1-12 were assessed for their inhibitory effects on nitric oxide (NO) in the LPS-induced BV-2 cells. The results showed that compounds 6 and 12 significantly inhibited the production of the inflammatory mediator NO, with an inhibitory rate of 95.96 and 91.13% at a concentration of 50 µM, respectively.

Stilbenes from the leaves of Cajanus cajan and their in vitro anti-inflammatory activities.

Eighteen stilbenes (1-18), including six previously undescribed ones (1-6), with diverse modification patterns were isolated from the leaves of edible and medicinal plant Cajanus cajan. Among the new isolates, compounds 1-3 were initially obtained as three racemic mixtures, which were further resolved into three pairs of optically pure enantiomers, respectively, by chiral HPLC. Besides, compounds 8, 10, 11, and 18 were obtained from C. cajan for the first time. The chemical structures and absolute configurations of the new stilbenes were elucidated unambiguously on the basis of extensive spectroscopic analyses, single crystal X-ray crystallographic study, and quantum chemical electronic circular dichroism (ECD) calculations. In addition, the in vitro anti-inflammatory activities of all isolated stilbenes were evaluated. Compounds 2, 9, 10, 11, and 14 exerted moderate suppression of nitric oxide (NO) secretion in lipopolysaccharide (LPS)-induced RAW264.7 cells without exhibiting substantial cytotoxicity.

Stilbene dimer xylosides and flavanols from the roots of Lysidice rhodostegia and their antioxidant activities.

Eight new stilbene dimer xylosides (1-8) and one new flavanol (9), along with seven known ones (10-16) were isolated from the roots of Lysidice rhodostegia. Their structures were elucidated by extensive analysis of spectroscopic data (IR, UV, HR-ESI-MS, 1D and 2D NMR), ECD calculations and acid hydrolysis. Compounds 1-16 were evaluated for their antioxidant activities using DPPH radical-scavenging assay. Especially, compounds 9 and 10 exhibited stronger antioxidant effects than the positive control (vitamin E), with IC50 values of 9.57 ± 1.30 and 13.60 ± 1.47 µM, respectively.

Rhodomentosones A and B: Two Pairs of Enantiomeric Phloroglucinol Trimers from Rhodomyrtus tomentosa and Their Asymmetric Biomimetic Synthesis.

Rhodomentosones A and B (1 and 2), two pairs of novel enantiomeric phloroglucinol trimers featuring a unique 6/5/5/6/5/5/6-fused ring system were isolated from Rhodomyrtus tomentosa. Their structures with absolute configurations were elucidated by NMR spectroscopy, X-ray crystallography, and ECD calculation. The bioinspired syntheses of 1 and 2 were achieved in six steps featuring an organocatalytic asymmetric dehydroxylation/Michael addition/Kornblum-DeLaMare rearrangement/ketalization cascade reaction. Compounds 1 and 2 exhibited promising antiviral activities against respiratory syncytial virus (RSV).

Five matrine-type alkaloids from Sophora tonkinensis.

Five matrine-type alkaloids (1‒5) including two new compounds (1 and 3) and a new natural product (2) were isolated from the roots of Sophora tonkinesis. Their structures were identified by extensive spectroscopic analysis (UV, IR, HRESIMS and NMR). The absolute configurations of 2 and 3 were determined by X-ray diffraction. Compounds 1‒5 were evaluated their activity against inflammatory cytokines TNF-α and IL-6 levels on LPS-induced RAW 264.7 macrophages, and compound 1 showed the most significant activity, potent than that of matrine, the representative ingredient from Sophora plants.

Two new isoquinoline alkaloids from the seeds of Nandina domestica.

Two new isoquinoline alkaloids, 6 R,6aS-N-nantenine Nß-oxide (1), 6S,6aS-N-nantenine Nα-oxide (2), along with nine known alkaloids, nantenine (3), oxonantenine (4), protopine (5), nornantenine (6), N-methyl-laurotetanine (7), isocorydine (8), O-methyflavinantine (9), N-methyl-2,3,6-trimethoxymorphinan-dien-7-one Nß-oxide (10) and (+)-10-O-methylhernovine Nß-oxide (11) were isolated from the seeds of Nandina domestica. Their structures were elucidated by extensive analyses of spectroscopic data (IR, UV, HRESIMS, 1 D and 2 D NMR), ECD calculation and comparison with the related literatures. In addition, the cytotoxicity against A549 cells of these alkaloids was determined by the MTT assay.

ß-Carboline Alkaloids from the Seeds of Peganum harmala and Their Anti-HSV-2 Virus Activities.

Pegaharines A-G (1-6), six novel ß-carboline alkaloids representing three types of skeleton, were isolated from the seeds of Peganum harmala. Compound 1 is a peculiar ß-carboline alkaloid characterized by the unprecedented carbon skeleton of an azepine-indole system. Compounds 3-6 represent the first examples of heterodimers constructed from rare tetracyclic ß-carboline and classic tricyclic ß-carboline alkaloids. Compounds 1 and 2 were characterized by X-ray crystallography. Compound 4 exhibited strong antiviral activity against HSV-2, with an IC50 value of 2.12 ± 0.14 µM.

Cyperenoic acid, a sesquiterpene derivative from Croton crassifolius, inhibits tumor growth through anti-angiogenesis by attenuating VEGFR2 signal pathway in breast cancer.

BACKGROUND: Cyperenoic acid, one of the main chemical constituents of the root of Croton crassifolius, exhibited potent anti-angiogenic property on the zebrafish embryo model with little cytotoxicity. Nevertheless, its anti-angiogenic mechanism and anti-tumor effect have not been investigated. PURPOSE: To investigate the anti-angiogenic mechanisms of cyperenoic acid and evaluate it whether could exert anti-tumor effect by inhibiting angiogenesis. STUDY DESIGN: Targeting vascular endothelial growth factor receptor-2 (VEGFR2) pathway to inhibit tumor angiogenesis is a significant strategy for cancer treatment. Initially, the anti-angiogenic effect of cyperenoic acid as well as the mechanisms of the action was studied using both in-vitro and in-vivo methodologies. Then, its anti-tumor effect through anti-angiogenesis by attenuating VEGFR2 signaling pathway was evaluated. METHODS: The in-vitro inhibitory effect of cyperenoic acid on the vascular endothelial growth factor (VEGF)-induced angiogenesis was evaluated using human umbilical vein endothelial cells (HUVECs) model. Moreover, its ex-vivo and in-vivo effects were evaluated using the aortic ring assay and the matrigel plug assay. The influence of the cyperenoic acid on tyrosine phosphorylation of VEGFR2 was studied by western blotting assay and the influence on downstream signaling pathway of VEGFR2 also be detected. Computer-docking simulations were carried out to study the interaction between cyperenoic acid and VEGFR2. Finally, its inhibitory effect on tumor growth was studied using breast cancer xenograft model. RESULTS: Cyperenoic acid possessed little toxicity to HUVECs, but it significantly inhibited VEGF-induced proliferation, invasion, migration and tube formation of HUVECs. Moreover, it inhibited VEGF-induced sprout formation ex vivo and vessel formation in vivo. Further mechanistic study showed that cyperenoic acid could suppress VEGFR2 tyrosine kinase activity and alter its downstream signaling pathways in VEGF-induced HUVECs. In addition, it could form two hydrogen bonds with the ATP binding pocket of the VEGFR2 kinase domain by docking. For breast cancer xenograft model, cyperenoic acid suppressed tumor growth, but no obvious toxic pathologic changes were observed in mice. Besides, it suppressed the phosphorylation of VEGFR2 in tumor, demonstrating its anti-angiogenic ability in vivo partly targeting the VEGFR2. CONLUSION: Cyperenoic acid could exert anti-tumor effect in breast cancer by inhibiting angiogenesis via VEGFR2 signaling pathway.

Caffeic acid oligomers from Mesona chinensis and their In Vitro antiviral activities.

The phytochemical study of the aerial part of Mesona chinensis led to the isolation of five new caffeic acid oligomers (1-5), as well as four known analogues (6-9). The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic analysis, chemical method, and quantum-chemical electronic circular dichroism (ECD) calculation. Among the isolates, compound 7 showed significant in vitro antiviral activity on respiratory syncytial virus (RSV).

Chemical constituents from the thorns of Gleditsia sinensis and their cytotoxic activities.

A new aromatic glycoside (1) and a new natural product, neolignan (2), along with twenty-three known compounds (3-25), were isolated from the thorns of Gleditsia sinensis. According to the spectroscopic analyses (IR, UV, HRESIMS, NMR and ECD), the structures of isolates were elucidated. Herein, compounds 4, 6-8, 10-13, 15, 16, 18, 20, 23 were isolated from the plant of G. sinensis for the first time. Moreover, compounds 4, 6, 15 and 24 showed cytotoxic effects on human ovarian cancer (SKOV-3) cells with IC50 values of 24.83 ± 4.90, 48.86 ± 9.11, 80.13 ± 5.62, 15.38 ± 2.21 µM, respectively. [Formula: see text].

Three new bisflavonols from the seeds of Hovenia dulcis Thunb. and their anti-RSV activities.

Three novel bisflavonol derivatives, Hovenianins A-C, along with 12 known flavonoids were isolated and identified from the seeds of Hovenia dulcis Thunb. Their structures were established on the basis of spectroscopic methods (MS, UV, IR, 1D and 2D NMR) and electronic circular dichroism experiments. Hovenianin A (1) was the first dimer of flavonol linked dihydroflavonol via the B rings at C-2' and C-2″'positions to be found in nature. While Hovenianins BC (2-3) were a pair of diastereoisomeric bis-dihydroflavonols firstly reported in the Hovenia genus. The in vitro antiviral activity against respiratory syncytium virus (RSV) were evaluated by cytopathic effect (CPE) reduction assay. As a result, compounds 4, 5, and 10 displayed better antiviral effect against RSV A2 strains.

Three new acylphloroglucinol glucosides from the roots of Lysidice rhodostegia and their antioxidant activities.

Three new acylphloroglucinol glucosides, rhodosides A-C (1-3), and three known ones (4-6) were isolated from the roots of Lysidice rhodostegia. The new structures were identified by MS, NMR, and acid hydrolysis. In addition, the antioxidant capacities of the isolated compounds were evaluated using DPPH radical-scavenging assay, and compounds 1-6 exhibited obvious antioxidant activities with IC50 values of 24.65 ± 1.27 to 38.11 ± 1.35 µM.

Quinolizidine alkaloids from Sophora tonkinensis and their anti-inflammatory activities.

Two new quinolizidine-based alkaloids (2 and 12), along with ten known ones (1, 3-11) were isolated from the roots of S. tonkinensis. Their structures were determined by spectroscopic data (including NMR, MS, IR, and UV), X-ray single crystal diffraction, electronic circular dichroism analyses (ECD), and comparing with related literatures. Compounds 1, 3-12 at non-toxic concentrations exhibited potent anti-inflammatory activities according to in vitro and in vivo anti-inflammatory tests. Among them, (-)-anagyrine (4), sophocarpine (8), 14ß-hydroxymatrine (10), and 7ß-sophoramine (12) showed more potent in vitro anti-inflammatory activities, and 5α,14ß-dihydroxymatrine (2), (-)-anagyrine (4), sophocarpine (8), and 5α-hydroxymatrine (9) exhibited better in vivo anti-inflammatory effects.

Three new alkaloids from the roots of Sophora tonkinensis.

A new ß-carboline alkaloid (1) and two new matrine-type alkaloids (2 and 3), together with two known alkaloids (4 and 5), were isolated from the roots of Sophora tonkinensis. The new structures were elucidated via extensive analyses of the spectroscopic data (IR, UV, HRESIMS, NMR) and X-ray crystallography. The absolute configuration of 1 was established by electronic circular dichroism data. Herein, is the first report of ß-carboline alkaloid in the plant of genus Sophora. In addition, the cytotoxic activities against HepG2 cells of compounds 1-5 were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Among them, compounds 1, 4 and 5 showed a weak cytotoxic activity with IC50 values of 87.4 ± 7.1, 91.8 ± 3.5 and 48.9 ± 5.2 µM, respectively.

PHMH, a diarylheptanoid from Alpinia officinarum attenuates VEGF-induced angiogenesis via inhibition of the VEGFR-2 signaling pathway.

The rhizome of Alpinia officinarum Hance, a popular spice used as a condiment in China and Europe, has various reported bioactivities, including anticancer, anti-inflammatory and antioxidant effects. However, its anti-angiogenic activity has not previously been reported. In this study, a diarylheptanoid was isolated from Alpinia officinarum and identified as 1-phenyl-7-(4-hydroxy-3-methoxyphenyl)-4E-en-3-heptanone (PHMH). We demonstrated that PHMH exerts anti-angiogenic activity both in vitro and in vivo. PHMH inhibited vascular endothelial growth factor (VEGF)-induced viability, migration, invasion and tube formation in human umbilical vein endothelial cells (HUVECs) in vitro, and also suppressed VEGF-induced sprout formation of rat aorta ex vivo. Furthermore, PHMH was found to block VEGF-induced vessel formation in mice and suppress angiogenesis in both zebrafish and chorioallantoic membrane models. Mechanistic studies indicated that PHMH inhibited VEGF-induced VEGF receptor-2 (VEGFR-2) auto-phosphorylation and resulted in the blockage of VEGFR-2-mediated signaling cascades in HUVECs, including the Akt/mTOR, ERK1/2, and FAK pathways. Our findings provide new insights into the potential application of PHMH as a therapeutic agent for anti-angiogenesis.

Antiviral activity of ethanol extract of Lophatherum gracile against respiratory syncytial virus infection.

ETHNOPHARMACOLOGICAL RELEVANCE: Lophatherum gracile, an important medicinal plant, is used traditionally in the treatment of cough associated with lung heat and inflammation. In this study, an ethanol extract of L. gracile (DZY) was shown to inhibit respiratory syncytial virus (RSV) infection and RSV-induced inflammation in vitro and in vivo. These findings provide a strong and powerful support for the traditional use of L. gracile in the treatment of RSV-related diseases. AIM OF THE STUDY: To determine the anti-RSV activities of DZY and its ingredients, and explore the relationship between RSV infection and inflammation. MATERIALS AND METHODS: DZY was extracted from L. gracile and its major ingredients were determined by high-performance liquid chromatography (HPLC). RSV-infected HEp-2 and RAW264.7 cell models were established to assess the inhibitory effect of DZY on RSV replication and nitric oxide (NO) production in vitro. Three-week-old BALB/c mice challenged intranasally with RSV were used to establish RSV-infected animal mode. The mice were respectively administered DZY at high-, middle-, and low-dose in different groups. The anti-RSV activity of DZY was evaluated by detecting viral load, lung lesion, CD4+ and CD8+ T cell population, and interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ expression in the lung tissue. RESULTS: In HEp-2 cell line, DZY effectively inhibited RSV infection in a dose-dependent manner with IC50 values of 20 µg/mL against RSV (Long strain) and IC50 values of 25 µg/mL against RSV (A2 strain). The anti-RSV activity of DZY was mainly determined by isoorientin, swertiajaponin, 3, 5-di-caffeoylquinic acid, and 3, 4-di-caffeoylquinic acid. Moreover, DZY suppressed NO production induced by RSV in vitro. In vivo, oral administration of DZY significantly reduced the viral load and ameliorated lesions in the lung tissue. A probable antiviral mechanism was mediated by slightly improving the ratio of CD4+/CD8+ T cells and inhibiting the mRNA and protein expression of IL-1ß, TNF-α, and IFN-γ. CONCLUSIONS: (1) DZY exhibits anti-RSV activities both in vitro and in vivo. (2) RSV infection can trigger a series of inflammatory reactions; thus, ameliorating inflammation is helpful to control the course of disease caused by RSV. These findings provide the rationale and scientific evidence behind the extensive use of L. gracile in traditional medicine for the treatment of diseases potentially caused by RSV.

Small molecule inhibits respiratory syncytial virus entry and infection by blocking the interaction of the viral fusion protein with the cell membrane.

Antiviral drug development against respiratory syncytial virus (RSV) is urgently needed due to the public health significance of the viral infection. Here, we report the anti-RSV activity of a small molecule, (1S,3R,4R,5R)-3,4- bis{[(E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxy}-1,5-dihydroxycyclohexane-1-carboxylic methyl ester (3,4-DCQAME) or 3,4- O-Dicaffeoylquinic acid methyl ester, which can be isolated from several plants of traditional Chinese medicine. We showed for the first time that compound 3,4-DCQAME potently inhibits RSV entry and infection. In vitro, 3,4-DCQAME can interact with F(ecto), the ectodomain of RSV fusion (F) protein. In cultured cells, the compound can block the interaction of F(ecto) protein with the cellular membrane and inhibit viral fusion during RSV entry, leading to inhibition of viral gene expression and infection. In RSV-infected mice that were treated with 3,4-DCQAME, we observed a reduction of RSV-induced pathologic changes and substantial inhibition of viral infection and growth in the lung tissues. Our results provide the first direct evidence of the anti-RSV activity of 3,4-DCQAME. Furthermore, these results suggest that 3,4-DCQAME represents a promising lead compound for anti-RSV therapeutic development.-Tang, W., Li, M., Liu, Y., Liang, N., Yang, Z., Zhao, Y., Wu, S., Lu, S., Li, Y., Liu, F. Small molecule inhibits respiratory syncytial virus entry and infection by blocking the interaction of the viral fusion protein with the cell membrane.

Terpenoids from the stems of Celastrus hindsii and their anti-RSV activities.

Two new oleanane-type triterpenoids (1-2), a new ursane-type triterpenoid (3), and a new podocarpane-type diterpenoid (4), together with 20 known compounds (5-24) were isolated from the stems of Celastrus hindsii Benth. Their structures were identified on the basis of the spectral data (HRESIMS, IR, UV, 1D, and 2D NMR) and the absolute configurations were determined by comparison of experimental and calculated ECD data. The structures of 1 and 4 were further confirmed by single crystal X-ray diffraction analysis. In addition, all compounds were evaluated for their in vitro antiviral activities against respiratory syncytium virus (RSV) using cytopathic effect (CPE) reduction assay. Compounds 7, 10, 11, 19 and 24 exhibited obvious anti-RSV activity with IC50 values from 1.55 to 6.25 µM.

Isodeoxyelephantopin induces protective autophagy in lung cancer cells via Nrf2-p62-keap1 feedback loop.

Isodeoxyelephantopin (ESI), isolated from Elephantopus scaber L. has been reported to exert anticancer effects. In this study, we aimed to investigate whether and how cancer cells exert protective responses against ESI treatment. Confocal fluorescence microscopy showed that ESI significantly induced autophagy flux in the lung cancer cells expressing mCherry-EGFP-LC3 reporter. Treatment of the cells with ESI increased the expression levels of the autophagy markers including LC3-II, ATG3 and Beclin1 in a dose-dependent manner. Pretreatment with autophagy inhibitor 3-methyladenine (3-MA) not only attenuated the effects of ESI on autophagy, but also enhanced the effects of ESI on cell viability and apoptosis. Mechanistically, the SILAC quantitative proteomics coupled with bioinformatics analysis revealed that the ESI-regulated proteins were mainly involved in Nrf2-mediated oxidative stress response. We found that ESI induced the nuclear translocation of Nrf2 for activating the downstream target genes including HO-1 and p62 (SQSTM1). More importantly, ESI-induced p62 could competitively bind with Keap1, and releases Nrf2 to activate downstream target gene p62 as a positive feedback loop, therefore promoting autophagy. Furthermore, knockdown of Nrf2 or p62 could abrogate the ESI-induced autophagy and significantly enhanced the anticancer effect of ESI. Taken together, we demonstrated that ESI can sustain cell survival by activating protective autophagy through Nrf2-p62-keap1 feedback loop, whereas targeting this regulatory axis combined with ESI treatment may be a promising strategy for anticancer therapy.