Inhibiting Angiogenesis by Anti-Cancer Saponins: From Phytochemistry to Cellular Signaling Pathways.

Saponins are one of the broadest classes of high-molecular-weight natural compounds, consisting mainly of a non-polar moiety with 27 to 30 carbons and a polar moiety containing sugars attached to the sapogenin structure. Saponins are found in more than 100 plant families as well as found in marine organisms. Saponins have several therapeutic effects, including their administration in the treatment of various cancers. These compounds also reveal noteworthy anti-angiogenesis effects as one of the critical strategies for inhibiting cancer growth and metastasis. In this study, a comprehensive review is performed on electronic databases, including PubMed, Scopus, ScienceDirect, and ProQuest. Accordingly, the structural characteristics of triterpenoid/steroid saponins and their anti-cancer effects were highlighted, focusing on their anti-angiogenic effects and related mechanisms. Consequently, the anti-angiogenic effects of saponins, inhibiting the expression of genes related to vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-α (HIF-1α) are two main anti-angiogenic mechanisms of triterpenoid and steroidal saponins. The inhibition of inflammatory signaling pathways that stimulate angiogenesis, such as pro-inflammatory cytokines, mitogen-activated protein kinase (MAPKs), and phosphoinositide 3-kinases/protein kinase B (PI3K/Akt), are other anti-angiogenic mechanisms of saponins. Furthermore, the anti-angiogenic and anti-cancer activity of saponins was closely related to the binding site of the sugar moiety, the type and number of their monosaccharide units, as well as the presence of some functional groups in their aglycone structure. Therefore, saponins are suitable candidates for cancer treatment by inhibiting angiogenesis, for which extensive pre-clinical and comprehensive clinical trial studies are recommended.

Evaluation of the Cytotoxicity of Aqueous Extract and Oleo-Essential Oil of Dorema ammoniacum Plant Oleo-Gum Resin in Some Human Cancer Cell Lines.

Results: Aqueous extract and essential oil reduced the viability of A549 cancer cells in a concentration-dependent manner. The lowest inhibitory concentrations (IC50) for both samples of D. ammoniacum oleo-gum resin were 10 and 2.5 µg/ml for 24 hours in A549 cell line, respectively. After treatment with extract and essential oil of D. ammoniacum oleo-gum resin, ROS increased significantly compared to the control group. Although changes in caspase-3 did not show a significant increase in extract, the caspase-3 was found to be increased after exposure to essential oil and caspase-9 was downregulated after exposure to essential oil. Also, exposure to essential oil of D. ammoniacum caused a reduction in MMP level. Conclusion: Based on results, the cytotoxic effect of essential oil of D. ammoniacum can induce apoptosis toward A549 cell line via induction of oxidative stress, MMP depletion, and caspase-3 activation, which is independent to mitochondrial cytochrome c release and caspase-9 function.

Comparison of the cytotoxic effects of different fractions of Artemisia ciniformis and Artemisia biennis on B16/F10, PC3 and MCF7 Cells.

BACKGROUND AND PURPOSE: Artemisia is one of the well-known herbal medicinal plants for antimicrobial, insecticidal, antioxidant, and antimalarial activities. The antiproliferative effects of dichloromethane extracts of Artemisia biennis (A. biennis) and A. ciniformis and the petroleum ether extract of A. ciniformis have been demonstrated previously on human cancerous cell lines. In the current study, further fractionation was carried out on the aforementioned extracts and their cytotoxic effects were evaluated on three human cancer cell lines; B16/F10, PC3, and MCF7. F1 to F16, F1' to F11', and F1" to F10" were resulted from the fractionation of dichloromethane extracts of A. biennis, A. ciniformis, and petroleum ether extract of A. ciniformis, respectively. EXPERIMENTAL APPROACH: The cytotoxic effects of 16 (F1-F16), 11 (F1'-F11') and 10 (F1"-F10") fractions, on B16/F10, PC3, and MCF7 cell lines were assessed using resazurin to measure viability and propidium iodide staining (sub G1) and flow cytometry to detect apoptosis. FINDINGS / RESULTS: The results showed that, some fractions at 100 µg/mL decreased cell viability. F2" in B16/F10 cells, F2, F4-F6, F10', F11', and F2" in PC3 cells, and F10', F11', and F2" in MCF7 significantly decreased cell viability in a concentration-dependent manner (12.5-50 µg/mL). Among different fractions, F2" demonstrated the most potent cytotoxic effects on cancer cell lines (P < 0.001). All of the mentioned fractions (except F11' on PC3 cells) increased the number of apoptotic cells and showed the cytotoxic effects on cancer cells compared with the control group. CONCLUSION AND IMPLICATIONS: A. biennis and A. ciniformis are suggested as the potential sources of cytotoxic phytochemicals. The probable presence of terpenoids, steroids, and alkaloids in the selected fractions is proposed based on the preliminary phytochemical study.

Isofraxidin: Synthesis, Biosynthesis, Isolation, Pharmacokinetic and Pharmacological Properties.

Isofraxidin (7-hydroxy-6, 8-dimethoxy coumarin) (IF) is a hydroxy coumarin with several biological and pharmacological activities. The plant kingdom is of the most prominent sources of IF, which, among them, Eleutherococcus and Fraxinus are the well-known genera in which IF could be isolated/extracted from their species. Considering the complex pathophysiological mechanisms behind some diseases (e.g., cancer, neurodegenerative diseases, and heart diseases), introducing IF as a potent multi-target agent, which possesses several herbal sources and the multiple methods for isolation/purification/synthesis, along with the unique pharmacokinetic profile and low levels of side effects, could be of great importance. Accordingly, a comprehensive review was done without time limitations until February 2020. IF extraction methods include microwave, mechanochemical, and ultrasound, along with other conventional methods in the presence of semi-polar solvents such as ethyl acetate (EtOAc). In addition to the isolation methods, related synthesis protocols of IF is also of great importance. From the synthesis point of view, benzaldehyde derivatives are widely used as precursors for IF synthesis. Along with the methods of isolation and biosynthesis, IF pharmacokinetic studies showed hopeful in vivo results of its rapid absorption after oral uses, leading to different pharmacological effects. In this regard, IF targets varieties of inflammatory mediators including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), tumor necrosis factor-α (TNF-α), and matrix metalloproteinases (MMPs). thereby indicating anticancer, cardioprotective, and neuroprotective effects. This is the first review on the synthesis, biosynthesis, isolation, and pharmacokinetic and pharmacological properties of IF in combating different diseases.

Cytotoxic and Apoptogenic Sesquiterpenoids from the Petroleum Ether Extract of Artemisia aucheri Aerial Parts.

Different types of Artemisia aucheri extracts were reported to have various biological activities including a cytotoxic effect on some cancer cell lines. We investigated the antiproliferative activity of isolated sesquiterpenoids from petroleum ether extract of Artemisia aucheri (A. aucheri) aerial parts on SK-N-MC, MCF-7, and A2780 cell lines. Phytochemicals from the petroleum ether cold macerated extract were isolated using normal phase vacuum liquid chromatography and high pressure liquid chromatography (VLC and HPLC) and the structures of the components were determined by spectroscopic means. Cell viability was determined by 3-(4,5- dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide assay. Activation of caspases-3 and -9 was evaluated using a spectrophotometer. Mitochondrial membrane potential (MMP) was measured using rhodamine 123 fluorescent dye. Two tetrahydrofuran- type sesquiterpenoids, hydroperoxide of davanone (1) and hydroxydavanone (2) were isolated and characterized. Between these compounds, compound 1 exhibited more potent activity against the MCF-7, SK-N-MC and A2780 cell lines with IC50 values of 8.45 ± 0.81 µg/mL, 9.60 ± 1.32 µg/mL and 10.9 ± 2.03 µg/mL in A2780, MCF-7 and SK-N-MC cells, respectively. Compound 1 inhibited the growth of human cancer cells by induction of apoptosis. To the best of our knowledge, this is the first comprehensive study on cytotoxic and apoptotic mechanism of two davanone derivatives isolated from A. aucheri in human cancer cells. Overall, our data suggest that hydroperoxide of davanone (1) should be further studied in-vivo as a potential antitumor agent.

2-Methylpyridine-1-ium-1-sulfonate from Allium hirtifolium: An anti-angiogenic compound which inhibits growth of MCF-7 and MDA-MB-231 cells through cell cycle arrest and apoptosis induction.

Natural products have well been recognized as sources of drugs in cancer treatment. Some medicinal plants contain the constituents with potent anti-angiogenic and anti-cancer effects, which have offered great hopes of being used as drugs for treating various cancers. The present study aims at identifying the anti-angiogenic effects of 2-Methylpyridine-1-ium-1-sulfonate (MPS) isolated from the ethyl acetate extract (EA) of Persian shallot (Allium hirtifolium). In a concentration-dependent manner, the MPS was able to inhibit endothelial cell migration and angiogenesis in both in vivo and in vitro assays, and also significantly suppressed proliferation of MCF-7 and MDA-MB-231 human breast cancer cell lines. Additionally, treatment with MPS showed a significant reduction in the vascular endothelial growth factor (VEGF) secretion level and production/activity of matrix metalloproteinases (MMP-2 and MMP-9) in the studied cells. The flow cytometry analysis indicated that MPS suppressed growth of MCF-7 and MDA-MB-231 cells at G0/G1 and S phases, respectively. Our results indicated that the induction of cell cycle arrest was correlated with the obvious changes in expression of p21, p27 and p53. According to the DNA fragmentation assay, MPS caused apoptosis in both cell lines, which confirms the results obtained with the growth assay. Moreover, the compound-mediated apoptosis accompanied with the increase in the Bax/Bcl-2 ratio and caspase-3 and -9 activities. Molecular docking results indicated that the MPS compound can surprisingly bind to VEGF and VEGF receptors and interacts with their critical amino acids. Finally, compounds with anticancer inhibitory activity (e.g. MPS) are abundant in nature and can be obtained from several sources. So, our data can be clinically developed for treating angiogenesis and cancer significantly.

Cytotoxic Properties of Three Isolated Coumarin-hemiterpene Ether Derivatives from Artemisia armeniaca Lam.

Considering multiple reports on cytotoxic activity of the Artemisia genus and its phytochemicals, in the current study A. armeniaca Lam. and the three components isolated from the plant were subjected to cytotoxic studies. Analytical fractionation of A. armeniaca aerial parts for the first time was directed to the isolation of 7-hydroxy-8-(4-hydroxy-3-methylbutoxy) comarin (armenin), 8-hydroxy-7-(4-hydroxy-3-methylbutoxy) comarin (isoarmenin) and deoxylacarol. Cytotoxicity assessed with alamalBlue® assay and apoptosis was detected by PI staining and western blot analysis of Bax and PARP proteins. Extracts and all compounds exhibited cytotoxic activity against apoptosis-proficient HL-60 and apoptosis-resistant K562 cells, with the lowest cytotoxic activity on J774 cell line as non-malignant cell. Armenin as the most potent component decreased the viability of cell with IC50 of 22.5 and 71.1 µM for K562 and HL-60 cells respectively and selected for further mechanistic study. Armenin increased the sub-G1 peak in flow cytometry histogram of HL-60 and K562 treated cells and increase in the amount of Bax protein and the cleavage of PARP in comparison with the control after treatment for 48 h in K562 treated cells verified the apoptotic activity of the armenin. Taken together, according to the finding of this study armenin was introduced as a novel cytotoxic compound with apoptotic activity, which is encouraging for further mechanistic and clinical studies.

Cytotoxic and apoptotic effects of different extracts of Artemisia biennis Willd. on K562 and HL-60 cell lines.

OBJECTIVES: Artemisia is a genus of herbs and small shrubs forms an important part of natural vegetation in Iran. It has been reported that several Artemisia species possess anti-proliferative effects. Considering the value of this genus in anti-cancer researches we have chosen Artemisia biennis for cytotoxic and mechanistic studies. MATERIALS AND METHODS: In this study we have investigated the cytotoxic and apoptotic effects of petroleum ether, dichloromethane, ethyl acetate, ethanol, and ethanol: water (1:1 v/v) extracts of A. biennis Willd. on two cancer human cell lines (K562 and HL-60) and J774 as normal cells. RESULTS: CH2Cl2 extract was found to have the highest anti-proliferative effect on cancer cells. IC50 values obtained in AlamarBlue® assay for CH2Cl2 extract were 64.86 and 54.31 µg/ml on K562 and HL-60 cells respectively. In flow cytometry histogram of the cells treated with CH2Cl2 extract, sub-G1 peak was induced. DNA fragmentation, increased in the level of Bax and cleavage of PARP protein all showed the induction of apoptosis with CH2Cl2 extract after 48 hr contact with cells. CONCLUSION: The results can corroborate the cytotoxic and apoptotic effects of the CH2Cl2 extract of A. biennis on the K562 and HL-60 cancer cell lines.

Evaluation of anti-aphthous activity of decoction of Nicotiana tabacum leaves as a mouthwash: a placebo-controlled clinical study.

OBJECTIVE: To determine the effects of decoction derived from the leaves of Nicotiana tabacum (L.) as a mouthwash on minor recurrent aphthous. METHODS: A randomized double-blinded placebo-controlled clinical trial was conducted on 60 patients with minor recurrent aphthous. Treatment comprised of application of tobacco or placebo mouthwash (10 mL 3 times a day) for 5 days. Clinical evaluation included pain level using a visual analog scale and ulcer size on days 1, 3, and 5 were measured. Adverse effects after mouthwash application were recorded, and the oral mucosa was examined by the investigator at each visit. RESULTS: A total of 54 subjects with the mean age (38 ± 10) years fulfilled the study. No minor and major adverse effects were observed. In the treatment group, ulcer pain score was decreased by 79.2% and 93.8% and ulcer size was reduced by 69.1% and 92.2% (days 3 and 5, respectively), which was significantly greater than the control group (P < 0.01). CONCLUSION: The decoction prepared with of Nicotiana tabacum leaves, used as mouthwash are well-tolerated and safe, and can be used for the management of recurrent aphthous.

Protective effects of fractions from Artemisia biennis hydro-ethanolic extract against doxorubicin-induced oxidative stress and apoptosis in PC12 cells.

OBJECTIVES: This study was designed to indicate whether different fractions from Artemisia biennis hydroethanolic extract could provide cytoprotection against oxidative stress and apoptosis induced by doxorubicin (DOX) in rat pheochromocytoma cell line (PC12). MATERIAL AND METHODS: Cell viability was determined by MTT assay. Also, activation of caspase-3 and superoxide dismutase were evaluated by spectrophotometry. Detection of reactive oxygen species (ROS) and measurement of mitochondrial membrane potential (MMP) were performed by flowcytometry. RESULTS: Treatment of PC12 cells with DOX reduced viability dose dependently. For evaluation of the effect of fractions (A-G) on DOX-induced cytotoxicity, PC12 cells were pretreated for 24 hr with the A. biennis fractions and then cells were treated with DOX. The fractions C and D increased PC12 cells viability significantly compared to DOX treated cells. Moreover, pretreatment with fractions C and D for 24 hr attenuated DOX-mediated apoptosis and the anti-apoptotic action of A. biennis fractions was partially dependent on inhibition of caspase 3 activity and also increasing the mitochondrial membrane potential (MMP). Selected A. biennis fractions also suppressed the generation of ROS and increased superoxide dismutase (SOD) activity. CONCLUSION: Taken together our observation indicated that subtoxic concentration of aforementioned fractions of A. biennis hydroetanolic extract has protective effect against apoptosis induced by DOX in PC12 cell. The results highlighted that fractions C and D may exert cytoprotective effects through their antioxidant actions.

A semipolar fraction of petroleum ether extract of Artemisia aucheri induces apoptosis and enhances the apoptotic response to doxorubicin in human neuroblastoma SKNMC cell line.

Artemisia is an important genus of Iranian flora whose potent anti-proliferative effect has been demonstrated previously on human cancerous cell lines. In the current study, further fractionation was carried out on the petroleum ether extract of A. aucheri and their cytotoxic effects were evaluated on three human cancer cell lines. Cell viability was determined by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide assay. Real time polymerase chain reaction (RT-PCR) was used to evaluate the expression of apoptotic related genes. Activation of caspases and detection of intracellular doxorubicin (DOX) accumulation were evaluated using a spectrophotometer. Mitochondrial membrane potential (MMP) was measured using flow cytometry. The fraction NO-7 (F7) of petroleum ether extract showed the highest anti-proliferative effect, especially against SKNMC cells. Therefore, we focused on a description of the cytotoxic mechanism of the most potent fraction on SKNMC cells. The results indicated that F7 was able to induce apoptosis through MMP disruption, activation of caspases and increament of proapoptotic genes Bax and Smac/DIABLO. Moreover, our observation indicated that F7 is able to increase the cytotoxicity of DOX in SKNMC cells. The combination of F7+DOX significantly increased the intracellular accumulation of DOX. These results indicated that F7 induces apoptosis in SKNMC cells. Moreover, it might enhance the antitumor activity of DOX, through modulating the activity of multidrug resistant cancer cells and inducing apoptosis.

Cytotoxic and apoptotic effects of extracts of Artemisia ciniformis Krasch. and Popov ex Poljakov on K562 and HL-60 cell lines.

Artemisia, as one of the largest genera in the tribe Anthemideae of the Asteraceae comprises an important part of Iranian flora. While cytotoxic and apoptotic properties have already been reported for some species of the genus there is not any report on cytotoxic effects of A. ciniformis. Petroleum ether (40-60), dichloromethane, ethyl acetate, ethanol and ethanol-water (50:50) extracts of the aerial parts of A. cinformis were subjected to cytotoxic and apoptotic evaluations on two cancer human cell lines (K562 and HL-60) and on J774 normal cells. Among multiple extracts evaluated for cytotoxicity, dichloromethane (CH2Cl2) and petroleum ether (PE) extracts were shown to possess the highest anti-proliferative effects on HL-60 and K562 cells with IC50 values of 31.3 and 25.5 µg/ml respectively. Apoptosis induction verified by sub-G1 peaks was seen in flow cytometry histograms. Increase in the amount of Bax protein, formation of DNA fragments, and cleavage of PARP to 24 and 89 kDa sub units all confirmed induction of apoptosis by A. cinformis extracts. Taken together according to the result of the present study some extracts of A. cinformis could be considered as sources for natural cytotoxic compounds and further mechanistic and phytochemical studies are recommended to fully understand the underlying mechanisms of cancer cell death as well as identification of responsible phytochemicals.

Cytotoxic and apoptotic effects of different extracts of Artemisia turanica Krasch. on K562 and HL-60 cell lines.

Artemisia is an important genus of Iranian flora. Cytotoxic activities for some species of the genus have already been reported. In this study, we have investigated the cytotoxic effects of n-hexane, CH2Cl2, EtOAc, EtOH, and EtOH/H2O (1:1) extracts of A. turanica Krasch. on two human leukemic cancer cell lines (K562 and HL-60) and J774 as normal cells using alamarBlue (resazurin) assay. PI staining of the fragmented DNA and western blot analysis were used to evaluate the possible apoptotic effect of the extract. The CH2Cl2 extract of A. turanica showed the most antiproliferative effect on cancer cells among all tested extracts with IC50 values of 69 and 104 µ g/mL on K562 and HL-60 cells, respectively, whereas the normal cells were not affected significantly by this extract. Sub-G1 peak in the flow cytometry histogram of the cells treated with CH2Cl2 extract of A. turanica and cleavage of PARP protein confirmed the induction of apoptosis with CH2Cl2 extract. Taken together, the findings of the present work suggest the anticancer potential of CH2Cl2 extract of A. turanica on human leukemic cancer cell lines.

In vitro anti-proliferative and apoptotic activity of different fractions of Artemisia armeniaca

Anti-proliferative properties have been reported for certain species of the genus Artemisia. In this study, we investigated the cytotoxic and apoptotic effects of n-hexane, CH2Cl2, EtOAc, n-BuOH and H2O fractions obtained from a crude methanol extract of A. armeniaca on two myeloid cell lines, apoptosis-proficient HL60 cells and apoptosis-resistant K562 cells; in addition, J774 cells were used as a control. Among the solvent fractions of A. armeniaca, the CH2Cl2 fraction was found to have the largest anti-proliferative effect on cancer cells. The IC50 values obtained using an MTS assay for the CH2Cl2 fraction were 75 and 130 µg/ml for HL-60 cells and K562, respectively. The control cells were not significantly affected by this fraction. A flow cytometry histogram of cells treated with the CH2Cl2 fraction of A. armeniaca revealed a sub-G1 peak. DNA fragmentation, increased protein levels of Bax and cleavage of the poly (ADP-ribose) polymerase (PARP) protein confirmed the induction of apoptosis in cells after a 48-h exposure to the CH2Cl2 fraction. Our results corroborate the cytotoxic and apoptotic effects of the CH2Cl2 fraction of A. armeniaca on K562 and HL-60 cancer cell lines.

New coumarin-hemiterpene ether glucosides and a structurally related phenylpropanoic acid derivative from Artemisia armeniaca.

Two new coumarin-hemiterpene ether glucosides, 4'-O-(beta-D-glucopyranosyl) desoxylacarol (1), and 5-O-(beta-D-glucopyranosyl) lacarol (2), were isolated from the methanolic extract of the aerial parts of Artemisia armeniaca Lam. Their structures were established by means of spectroscopic analysis including 1H- and 2D-NMR, HRESIMS, and acid hydrolysis. In addition, a structurally related phenylpropanoic acid derivative (3) was obtained in small amounts, and its structure tentatively assigned as 3-(4-hydroxy-3-methylbutoxy)-4-methoxy melilotic acid.