Xanthatin,a novel potent inhibitor of VEGFR2 signaling,inhibits angiogenesis and tumor growth in breast cancer cells

Anti-angiogenesis targeting vascular endothelial growth factor receptor 2 (VEGFR2) has emerged as an important tool for cancer treatment. In this study, we described a novel VEGFR2 inhibitor, xanthatin, which inhibits tumor angiogenesis and growth. The biochemical profiles of xanthatin were investigated using kinase assay, migration assay, tube formation, Matrigel plug assay, western blot, immunofluorescence and human tumor xenograft model. Xanthatin significantly inhibited growth, migration and tube formation of human umbilical vascular endothelial cell as well as inhibited vascular endothelial growth factor (VEGF)-stimulated angiogenesis. In addition, it inhibited VEGF-induced phosphorylation of VEGFR2 and its downstream signaling regulator. Moreover, xanthatin directly inhibit proliferation of breast cancer cells MDA-MB-231. Oral administration of xanthatin could markedly inhibit human tumor xenograft growth and decreased microvessel densities (MVD) in tumor sections. Taken together, these preclinical evaluations suggest that xanthatin inhibits angiogenesis and may be a promising anticancer drug candidate.     

Screening and identification of vascular-endothelial-cell-specific binding peptide in gastric cancer

Antiangiogenesis therapy has become a hot field in cancer research. Blood vessels of tumor carry specific markers that are usually related to angiogenesis. Study of these heterogeneous molecules in different tumor vessels may be beneficial for promoting antiangiogenic therapy. In this study, we established an in vitro co-culture model of human umbilical vein endothelial cells (HUVECs) and gastric adenocarcinoma cell line SGC7901, screened the peptides binding specifically to the HUVECs co-cultured with gastric cancer cells (Co-HUVECs) using phage display peptides library, and studied the affinity of these peptides to gastric cancer vascular endothelial cells. After four rounds of panning, there was an obvious enrichment for the phages specifically binding to the Co-HUVECs, and the output/input ratio of Co-HUVECs increased about 590-fold (from 0.95×10⁻⁷ to 561.25×10⁻⁷). Five phage clones (M6, M3, M9, IN12, IN11), which could strongly bind to Co-HUVECs instead of wild-type HUVECs, were characterized by ELISA. In vitro cellular binding assay showed that phage IN11 preferably bound to Co-HUVECs rather than control HUVECs, and the number of the phage IN11 recovered from Co-HUVECs was 5.7- and 16.9-folds, respectively, as much as those from control HUVECs and GES cells. Immunocytochemical and immunohistochemical staining confirmed that phage IN11 could specifically bind to Co-HUVECs as well as vascular endothelial cells in gastric cancer tissue sections. Competitive and inhibitory assay revealed the synthetic peptide GEBP11 (CTKNSYLMC) displayed on phage IN11 could competitively inhibit binding of the phage IN11 to Co-HUVECs. Immunofluorescence microscopy showed that the fluorescence-labeled peptide GEBP11 was located at the membrane and perinuclear cytoplasm of Co-HUVECs. Meanwhile, GEBP11 was found to be able to target the gastric cancer vascular endothelial cells. Therefore, GEBP11 may be a potential candidate for targeted drug delivery in antivascular therapy and diagnosis of gastric cancer.     

Triptolide Suppresses Alkali Burn‐Induced Corneal Angiogenesis Along with a Downregulation of VEGFA and VEGFC Expression

Triptolide (TPL) is an active compound extracted from a Chinese herbal medicine tripterygium wilfordii Hook. f. (Celastraceae), which has been used as an anti‐inflammatory drug for years. It also inhibits the growth and proliferation of different types of cancer cells. The inhibitory effect of TPL on angiogenesis after chemical‐induced corneal inflammation was studied in vivo. The effects of TPL on the proliferation, apoptosis, migration, and tube formation of rat aortic endothelial cells (RAECs) were studied in vitro. Cell proliferation and apoptosis were measured by MTT assay and flow cytometry, respectively. Migration was analyzed using the scratch wound healing assay and transwell assay. Tube formation assay was used to examine angiogenesis. Real‐time PCR and Western blot were used to determine the expression of vascular endothelial growth factor A (VEGFA) and VEGFC. To study the in vivo effects of TPL, the mouse model of alkali burn‐induced corneal angiogenesis was used. The angiogenesis was analyzed by determining the density of the newly generated blood vessels in corneas. We found that TPL induced apoptosis and inhibited the proliferation of RAECs in a dose‐dependent manner. TPL inhibited migration and tube formation of RAECs and decreased the expression of VEGFA and VEGFC in vitro. Furthermore, TPL suppressed alkali burn‐induced corneal angiogenesis and inhibited the expression of VEGFA and VEGFC in corneas in vivo. In conclusion, topical TPL as a pharmacological agent has the ability to reduce angiogenesis in cornea and may have clinical indications for the treatment of corneal angiogenesis diseases which have to be further explored. Anat Rec, 300:1348–1355, 2017. © 2017 Wiley Periodicals, Inc.     

Anti-angiogenic effect of high doses of ascorbic acid

Pharmaceutical doses of ascorbic acid (AA, vitamin C, or its salts) have been reported to exert anticancer activity in vitro and in vivo. One proposed mechanism involves direct cytotoxicity mediated by accumulation of ascorbic acid radicals and hydrogen peroxide in the extracellular environment of tumor cells. However, therapeutic effects have been reported at concentrations insufficient to induce direct tumor cell death. We hypothesized that AA may exert anti-angiogenic effects. To test this, we expanded endothelial progenitor cells (EPCs) from peripheral blood and assessed, whether or not high dose AA would inhibit EPC ability to migrate, change energy metabolism, and tube formation ability. We also evaluated the effects of high dose AA on angiogenic activities of HUVECs (human umbilical vein endothelial cells) and HUAECs (human umbilical arterial endothelial cells). According to our data, concentrations of AA higher than 100 mg/dl suppressed capillary-like tube formation on Matrigel for all cells tested and the effect was more pronounced for progenitor cells in comparison with mature cells. Co-culture of differentiated endothelial cells with progenitor cells showed that there was incorporation of EPCs in vessels formed by HUVECs and HUAECs. Cell migration was assessed using an in vitro wound healing model. The results of these experiments showed an inverse correlation between AA concentrations relative to both cell migration and gap filling capacity. Suppression of NO (nitric oxide) generation appeared to be one of the mechanisms by which AA mediated angiostatic effects. This study supports further investigation into non-cytotoxic antitumor activities of AA.     

Inhibitory effect of midkine-binding peptide on tumor proliferation and migration

Background: To investigate the inhibitory effect of midkine-binding peptides on human umbilical vein endothelial cells (HUVECs) proliferation and angiogenesis of xenograft tumor. Methods: The midkine-binding peptides were panned by Ph.D.-7^™ Phage Display Peptide Library Kit, and the specific binding activities of positive clones to target protein were examined by phage ELISA. The effect of midkine-binding peptides on proliferation of HUVECs was confirmed by MTT test. The xenograft tumor model was formed in BALB/c mice with the murine hepatocarcinoma cells H22 (H22). Microvessel density (MVD) was analyzed by immunohistochemistry of factor VIII staining. Results: Midkine-binding peptides have the inhibitory effects on tumor angiogenesis, a proliferation assay using human umbilical vein endothelial cells (HUVECs) indicated that particular midkine-binding peptides significantly inhibited the proliferation of the HUVECs. Midkine-binding peptides were also observed to efficiently suppress angiogenesis induced by murine hepatocarcinoma H22 cells in BALB/c nude mice. Conclusion: The midkine-binding peptides can inhibit solid tumor growth by retarding the formation of new blood vessels. The results indicate that midkine-binding peptides may represent potent anti-angiogenesis agents in vivo.     

Low-dose metronomic chemotherapy with cisplatin: can it suppress angiogenesis in H22 hepatocarcinoma cells?

Low‐dose chemotherapy drugs can suppress tumours by restraining tumour vessel growth and preventing the repair of damaged vascular endothelial cells. Cisplatin is a broad‐spectrum, cell cycle‐non‐specific drug, but has serious side effects if used at high doses. There have been few reports on the anti‐angiogenic effects of low‐dose cisplatin and hence the effect of low‐dose metronomic (LDM) chemotherapy on the proliferation and neovascularization of H22 hepatocarcinoma cells is discussed in this research. The influence of LDM chemotherapy with cisplatin on human umbilical vascular endothelial cells (HUVECs) and proliferation of the HepG₂ human hepatocarcinoma cell line were measured using MTT assays. The LDM group was treated with cisplatin 0.6 mg/kg/day; the control group with saline 0.2 ml; the maximum tolerated dose (MTD) group with cisplatin 9 mg/kg/day. Vascular endothelial growth factor (VEGF) and matrix metallopeptidase 2 (MMP‐2) were detected using immunohistochemical staining. A chicken chorio‐allantoic membrane (CAM) model was used to check the inhibitory effect of LDM chemotherapy with cisplatin on neovascularization in vivo. Low‐dose cisplatin inhibited HUVEC proliferation in a dose‐ and time‐dependent manner, but was ineffective in inhibiting HepG₂ cell proliferation. Tumour growth was delayed in mice receiving LDM cisplatin, without apparent body weight loss, compared with mice that received MTD cisplatin. Microvessel density and expression of VEGF and MMP‐2 were much lower in mice receiving LDM cisplatin than in the control and MTD groups. Continuous low‐dose cisplatin suppressed CAM angiogenesis in vivo. LDM chemotherapy with cisplatin can inhibit the growth of blood vessel endothelial cells in vitro and shows anti‐angiogenic ability in vivo.     

雷公藤甲素对血管生成的抑制作用

利用体外培养人脐静脉内皮细胞,经不同浓度的雷公藤甲素(0、5、10、20、30μg/L)处理后,MTT法显示雷公藤甲素可抑制内皮细胞的增殖,5μg/L雷公藤甲素的抑制率达29.15%;琼脂凝胶立体细胞培养系统检测发现内皮细胞经雷公藤甲素作用后,其游走能力降低;鸡胚尿囊膜试验观察到雷公藤甲素可有效抑制血管的生成;荧光定量RT-PCR检测发现雷公藤甲素可下调内皮细胞u-PAmRNA的表达。因此认为,雷公藤甲素可能在基因水平上干扰内皮细胞u-PAmRNA的表达,减少u-PA蛋白的生成,从而有效地抑制血管内皮细胞的增殖和移行,这可能是雷公藤甲素抑制血管生成的主要机制之一。     

Antiangiogenic Activity of Acer tegmentosum Maxim Water Extract in Vitro and in Vivo

Angiogenesis, the formation of new blood vessels, is critical for tumor growth and metastasis. Notably, tumors themselves can lead to angiogenesis by inducing vascular endothelial growth factor (VEGF), which is one of the most potent angiogenic factors. Inhibition of angiogenesis is currently perceived as one of the most promising strategies for the blockage of tumor growth. In this study, we investigated the effects of Acer tegmentosum maxim water extract (ATME) on angiogenesis and its underlying signal mechanism. We studied the antiangiogenic activity of ATME by using human umbilical vein endothelial cells (HUVECs). ATME strongly inhibited VEGF-induced endothelial cell proliferation, migration, invasion, and tube formation, as well as vessel sprouting in a rat aortic ring sprouting assay. Moreover, we found that the p44/42 mitogen activated protein (MAP) kinase signaling pathway is involved in the inhibition of angiogenesis by ATME. Moreover, when we performed the in vivo matrigel plug assay, VEGF-induced angiogenesis was potently reduced when compared to that for the control group. Taken together, these results suggest that ATME exhibits potent antiangiogenic activity in vivo and in vitro and that these effects are regulated by the extracellular regulated kinase (ERK) pathway.

Graphical Abstract

相似文献   

N-acetylcysteine inhibits endothelial cell invasion and angiogenesis.

The thiol N-acetylcysteine (NAC) is a chemopreventive agent that acts through a variety of mechanisms and can prevent in vivo carcinogenesis. We have previously shown that NAC inhibits invasion and metastasis of malignant cells as well as tumor take. Neovascularization is critical for tumor mass expansion and metastasis formation. We investigated whether a target of the anti-cancer activity of NAC could be the inhibition of the tumor angiogenesis-associated phenotype in vitro and in vivo using the potent angiogenic mixture of Kaposi's sarcoma cell products as a stimulus. Two endothelial (EAhy926 and human umbilical vein endothelial [HUVE]) cell lines were utilized in a panel of assays to test NAC ability in inhibiting chemotaxis, invasion, and gelatinolytic activity in vitro. NAC treatment of EAhy926 and HUVE cells in vitro dose-dependently reduced their ability to invade a reconstituted basement membrane, an indicator of endothelial cell activation. Invasion of HUVE cells was inhibited with an ID50 of 0.24 mM NAC, whereas inhibition of chemotaxis required a 10 fold higher doses, indicating that invasion is a preferential target. NAC inhibited the enzymatic activity and conversion to active forms of the gelatinase produced by endothelial cells. The matrigel in vivo assay was used for the evaluation of angiogenesis; NAC strongly inhibited neovascularization of the matrigel sponges in response to Kaposi's sarcoma cell products. NAC prevented angiogenesis while preserving endothelial cells, implying that it could be safely used as an anti-angiogenic treatment.     

Crucial Role for Endothelial Cell α2β1 Integrin Receptor Clustering in Collagen-Induced Angiogenesis

Angiogenesis is a crucial mechanism of vascular growth and regeneration that requires biosynthesis and cross-linking of collagens in vivo and is induced by collagen in vitro. Here, we use an in vitro model in which apical Type I collagen gels rapidly induce angiogenesis in endothelial monolayers. We extend previous studies demonstrating the importance of the endothelial α2β1 integrin, a key collagen receptor, in angiogenesis by investigating the roles of receptor clustering and conformational activation. Immunocytochemical localization of α2β1 integrins in endothelial monolayers showed a concentration of integrins along cell–cell borders. After inducing angiogenesis with collagen, the receptors redistributed to apical cell surfaces, aligning with collagen fibers, which were also redistributed during angiogenesis. Levels of conformationally activated α2β1 integrins were unchanged during angiogenesis and undetected on endothelial cells binding collagen in suspension. We mimicked the polyvalency of collagen fibrils using antibody-coated polystyrene beads to cluster endothelial cell surface α2β1 integrins, which induced rapid angiogenesis in the absence of collagen gels. Clustering of αvβ3 integrins and PECAM-1 but not of α1 integrins also induced angiogenesis. Soluble antibodies alone had no effect. Thus, the angiogenic property of collagen may reside in its ability to ligate and cluster cell surface receptors such as α2β1 integrins. Furthermore, synthetic substrates that promote the clustering of select endothelial cell surface receptors mimic the angiogenic properties of Type I collagen and may have applications in promoting vascularization of engineered tissues. Anat Rec, 2019. © 2019 American Association for Anatomy     

Down-modulation of monocyte transendothelial migration and endothelial adhesion molecule expression by fibroblast growth factor: reversal by the anti-angiogenic agent SU6668

Basic and acidic fibroblast growth factor (bFGF and aFGF, respectively) and vascular endothelial growth factor (VEGF) exert angiogenic actions and have a role in wound healing, inflammation, and tumor growth. Monocytes and endothelial cells are involved in these processes, but the effect of FGF and VEGF on monocyte-endothelial cell interactions has not been defined. We observed that monocyte adhesion to resting or cytokine (tumor necrosis factor-alpha or interleukin-1 alpha)-stimulated human umbilical vein endothelial cells (HUVECs) was markedly inhibited (40 to 65%) by culture (1 to 6 days) of HUVECs with aFGF or bFGF. Monocyte transendothelial migration induced by C5a and chemokines (MCP-1, SDF-1 alpha, RANTES, MIP-1 alpha) was also suppressed (by 50 to 75%) on bFGF-stimulated HUVECs. VEGF did not have these effects at the concentrations used (10 to 20 ng/ml), although like bFGF, it promoted HUVEC proliferation. Culture of HUVECs with bFGF and aFGF significantly down-regulated intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin expression on resting or tumor necrosis factor-alpha-stimulated HUVECs, but had no influence on platelet endothelial cell adhesion molecule (PECAM)-1 and VE-cadherin expression. bFGF also inhibited MCP-1 production by HUVECs. The inhibitory effects of bFGF on monocyte transendothelial migration and adhesion molecule expression were reversed by SU6668, an anti-angiogenic agent and bFGF receptor tyrosine kinase inhibitor. Our results suggest that bFGF and aFGF may suppress endothelial-dependent monocyte recruitment and thus have an anti-inflammatory action during angiogenesis in chronic inflammation but inhibit the immunoinflammatory tumor defense mechanism. However, SU6668 is an effective agent to prevent this down-regulatory action of bFGF on monocyte-endothelial cell interactions.     

Heat Shock Protein 47 Promotes Glioma Angiogenesis

Heat shock protein 47 (HSP47) is a collagen‐binding protein, which has been recently found to express in glioma vessels. However, the expression profile of HSP47 in glioma patients and the underlying mechanisms of HSP47 on glioma angiogenesis are not fully explored. In the current study, we found that expression of HSP47 in glioma vessels was correlated with the grades of gliomas. HSP47 knockdown by siRNAs significantly decreased cell viability in vitro and tumor volume in vivo; moreover, it reduced the microvessel density (MVD) by CD31 immunohistochemistry in vivo. HSP47 knockdown significantly inhibited tube formation, invasion and proliferation of human umbilical vein endothelial cells (HUVECs). Furthermore, conditional medium derived from HSP47 knockdown cells significantly inhibited HUVECs tube formation and migration, while it increased chemosensitivity of HUVECs cells to Avastin. Silencing of HSP47 decreased VEGF expression in glioma cells consistently, and reduced glioma vasculature. Furthermore, HSP47 promoted glioma angiogenesis through HIF1α‐VEGFR2 signaling. The present study demonstrates that HSP47 promotes glioma angiogenesis and highlights the importance of HSP47 as an attractive therapeutic target of GBM.     

Myricetin Induces Protective Autophagy by Inhibiting the Phosphorylation of mTOR in HepG2 Cells

Myricetin, a natural flavonoid present in a variety of fruits and vegetables, has been studied as a promising cancer chemopreventive agent in many cancer models. It has been reported that myricetin could inhibit tumor promotion by inducing cell cycle arrest and promoting apoptotic cell death. At present, autophagy is considered to be closely associated with cancer, functioning as either an anti‐cancer or pro‐cancer mechanism depending on the cancer stage. Till date, the role of myricetin in regulating autophagy has not been reported. In this study, we found that myricetin can induce autophagy by inhibiting mTOR activation in HepG2 cells. Our findings thus provide evidence for further research and application of myricetin as a potential cancer therapeutic agent. Anat Rec, 301:786–795, 2018. © 2017 Wiley Periodicals, Inc.     

Delta-like ligand 4-targeted nanomedicine for antiangiogenic cancer therapy

Tumor angiogenesis is a multistep process involved with multiple molecular events in cancer microenvironment. Several molecular-targeted agents aiming to suppress tumor angiogenesis have been successfully translated into cancer clinic. However, new strategies are still urgently desired to be excavated to overcome the poor response and resistance in some antiangiogenic therapies. Recently, Delta-like ligand 4 (Dll4) is identified to be specifically over-expressed on tumor vascular endothelial cells (EC), and the Dll4-Notch pathway serves as a critical regulator in the development and maintenance of tumor angiogenesis. The intensively up-regulated phenotype of Dll4 on the membrane of tumor vascular EC implies that Dll4 may act as a targetable address for drug delivery system (DDS) to achieve targeted antiangiogenic cancer therapy. Here, a nano-DDS, GD16 peptide (H₂N-GRCTNFHNFIYICFPD-CONH₂, containing a disulfide bond between Cys₃ and Cys₁₃) conjugated nanoparticles loading paclitaxel (GD16-PTX-NP), which can specifically target the angiogenic marker Dll4, was fabricated for the investigation of antiangiogenic therapeutic efficacy in human head and neck cancer FaDu (Dll4-negative) xenograft in nude mice. The results demonstrate that GD16-PTX-NP achieved controlled drug release and exhibited favorable in vivo long-circulating feature. GD16-PTX-NP exerted enhanced antiangiogenic activity in the inhibition of human umbilical vein endothelial cell (HUVEC) viability, motility, migration, and tube formation, and in the Matrigel plug model as well, which can be definitely ascribed to the active internalization mediated by the interaction of GD16 and the over-expressed Dll4 on EC. GD16-PTX-NP showed accurate in vivo tumor neovasculature targeting property in FaDu tumor, where the paclitaxel was specifically delivered into the tumor vascular EC, leading to significant apoptosis of tumor vascular EC and necrosis of tumor tissues. The antiangiogenic activity of GD16-PTX-NP significantly contributed to its in vivo anticancer efficacy in Fadu tumor; moreover, no overt toxicity to the mice was observed. Our research firstly presents the potency and significance of a Dll4-targeted nanomedicine in antiangiogenic cancer therapy.     

LHT7, a chemically modified heparin,inhibits multiple stages of angiogenesis by blocking VEGF,FGF2 and PDGF-B signaling pathways

Despite the therapeutic benefits of the angiogenesis inhibitors shown in the clinics, they have encountered an unexpected limitation by the occurrence of acquired resistance. Although the mechanism of the resistance is not clear so far, the upregulation of alternative angiogenic pathways and stabilization of endothelium by mural cells were reported to be responsible. Therefore, blocking multiple angiogenic pathways that are crucial in tumor angiogenesis has been highlighted to overcome such limitations. To develop an angiogenesis inhibitor that could block multiple angiogenic factors, heparin is an excellent lead compound since wide array of angiogenic factors are heparin-binding proteins. In previous study, we reported a heparin-derived angiogenesis inhibitor, LHT7, as a potent angiogenesis inhibitor and showed that it blocked VEGF signaling pathway. Here we show that LHT7 could block the fibroblast growth factor 2 (FGF2) and platelet-derived growth factor B (PDGF-B) in addition to VEGF. Simultaneous blockade of these angiogenic factors resulted in inhibition of multiple stages of the angiogenic process, including initial angiogenic response to maturation of the endothelium by pericyte coverage in vitro. In addition, the treatment of LHT7 in vivo did not show any sign of vascular normalization and directly led to decreased blood perfusion throughout the tumor. Our findings show that LHT7 could effectively inhibit tumor angiogenesis by blocking multiple stages of the angiogenesis, and could potentially be used to overcome the resistance.     

Effects of lycopene and apigenin on human umbilical vein endothelial cells in vitro under angiogenic stimulation

Angiogenesis is the formation process of new blood vessels from preexisting vessels. Solid tumors need angiogenesis for growth and metastasis. The suppression of tumor growth by inhibition of neoangiogenic processes represents a potential approach to cancer treatment. Lycopene has powerful antioxidant capacities and anticarcinogenic properties. The aim of this study was to investigate the effects of lycopene on angiogenesis in vitro. For this reason, we measured in vitro angiogenesis in human umbilical vein endothelial cells including parameters of cell proliferation, tube formation, cell migration. Lycopene and apigenin were observed to block the endothelial cell proliferation in a dose-dependent manner. In addition, they significantly decreased the capillary-like tube lengths, tube formation and endothelial cell migration. This study provides indications that apigenin and lycopene, which are considered as chemopreventive agents, to be effective in vitro on endothelial cells and angiogenesis.     

Role of the estrogen antagonist ICI 182,780 in vessel assembly and apoptosis of endothelial cells

Angiogenesis is required during tumor progression. Emerging data, including the presence of estrogen receptors in endothelium, suggests that estrogens can mediate endothelial proliferation and differentiation. Therefore, it is likely that anti-estrogenic drugs can also exert their effects in endothelial cells. The purpose of this work was to evaluate the effect of one anti-estrogenic agent, ICI 182,780, in human umbilical vein endothelial cells (HUVECs). Treatment of HUVECs with 5 different concentrations of ICI 182,780 resulted in decreased cell viability and increase in apoptosis. Gene expression profile of these ICI-treated cells evaluated by cDNA array presented an upregulation of 68 newly expressed genes, whose expression was absent from both control and 17β-estradiol-treated HUVECs. Most of these genes were implicated in both intrinsic and extrinsic apoptotic pathways. Furthermore, ICI 182,780 incubation prevented HUVECs from formity capillary-like tubules in a Matrigel assay. These findings suggest that besides blocking tumor cell proliferation in an estrogen receptor-dependent manner, ICI 182,780 impaired angiogenesis by preventing branching and capillary-like tubule formation and by activating apoptotic pathways in endothelial cells.     

Ethyl-p-methoxycinnamate isolated from kaempferia galanga inhibits inflammation by suppressing interleukin-1, tumor necrosis factor-α, and angiogenesis by blocking endothelial functions

OBJECTIVE:

The present study aimed to investigate the mechanisms underlying the anti-inflammatory and anti-angiogenic effects of ethyl-p-methoxycinnamate isolated from Kaempferia galanga.

METHODS:

The anti-inflammatory effects of ethyl-p-methoxycinnamate were assessed using the cotton pellet granuloma assay in rats, whereby the levels of interleukin-1 and tumor necrosis factor-α were measured in the animals'' blood. In addition, the levels of interleukin, tumor necrosis factor, and nitric oxide were measured in vitro using the human macrophage cell line (U937). The analgesic effects of ethyl-p-methoxycinnamate were assessed by the tail flick assay in rats. The anti-angiogenic effects were evaluated first by the rat aortic ring assay and, subsequently, by assessing the inhibitory effects of ethyl-p-methoxycinnamate on vascular endothelial growth factor, proliferation, migration, and tube formation in human umbilical vein endothelial cells.

RESULTS:

Ethyl-p-methoxycinnamate strongly inhibited granuloma tissue formation in rats. It prolonged the tail flick time in rats by more than two-fold compared with the control animals. The inhibition of interleukin and tumor necrosis factor by ethyl-p-methoxycinnamate was significant in both in vivo and in vitro models; however, only a moderate inhibition of nitric oxide was observed in macrophages. Furthermore, ethyl-p-methoxycinnamate considerably inhibited microvessel sprouting from the rat aorta. These mechanistic studies showed that ethyl-p-methoxycinnamate strongly inhibited the differentiation and migration of endothelial cells, which was further confirmed by the reduced level of vascular endothelial growth factor.

CONCLUSION:

Ethyl-p-methoxycinnamate exhibits significant anti-inflammatory potential by inhibiting pro-inflammatory cytokines and angiogenesis, thus inhibiting the main functions of endothelial cells. Thus, ethyl-p-methoxycinnamate could be a promising therapeutic agent for the treatment of inflammatory and angiogenesis-related diseases.