Endostatin, a carboxyl-terminal fragment of collagen XVIII is known as an anti-angiogenic agent, that specifically inhibits the proliferation of endothelial cell and the growth of several primary tumor. We report here the purification and characterization of the recombinant murine endostatin (rmEndostatin) which was expressed in a prokaryotic expression system. This rmEndostatin has similar physiochemical properties of yeast-produced recombinant endostatin, and it also specifically inhibits the proliferation and migration of bovine capillary endothelial cells stimulated by basic fibroblast growth factor. The biological activity of rmEndostatin was also shown by its anti-angiogenic ability on the chorioallantoic membrane of chick embryo in vivo. In this article, we demonstrate the refolding and purification of rmEndostatin, expressed using E. coli system, to a biologically active and soluble form. In addition, these results confirm the activity of endostatin as a potent anti-angiogenic agent. Copyright 2000 Academic Press.
Angiogenesis Inhibitors/pharmacology* ; Angiogenesis Inhibitors/isolation & purification ; Angiogenesis Inhibitors/genetics* ; Animal ; Blotting, Western ; Cattle ; Cell Movement/drug effects ; Chick Embryo ; Chorion/pathology ; Chorion/drug effects ; Circular Dichroism ; Collagen/pharmacology* ; Collagen/isolation & purification ; Collagen/genetics* ; Electrophoresis, Polyacrylamide Gel ; Endothelium, Vascular/drug effects ; Endothelium, Vascular/cytology ; Escherichia coli/genetics* ; Fibroblast Growth Factor, Basic/pharmacology ; Mice ; Neovascularization, Physiologic/drug effects ; Peptide Fragments/pharmacology* ; Peptide Fragments/isolation & purification ; Peptide Fragments/genetics* ; Protein Folding ; Recombinant Proteins/pharmacology ; Recombinant Proteins/isolation & purification ; Recombinant Proteins/genetics ; Solubility ; Yeasts/genetics

Arg-Gly-Asp (RGD)-toxin protein Lj-RGD3 of Lampetra japonica shares homologous with a Histidine-rich glycoprotein (HRG), and both RGD-toxin protein and HRG have antiangiogenic activities with different targets. To study the relationship between the function and the structure of Lj-RGD3, we studied the anti-angiogenic characteristics of both Lj-RGD3 and the mutation named Lj-112 of which three RGD motifs of Lj-RGD3 were deleted. We synthesized the gene of Lj-112, constructed it to the plasmid pET23b, and expressed the recombinant proteins in Escherichia coli BL21. Both recombinant proteins with the C-terminal his-tag were 15 kDa soluble proteins. Then we purified rLj-RGD3 and rLj-112 using the His-Bind affinity chromatography. To examine the effect of both proteins on bFGF-induced proliferation of ECV304 cell, we carried out the 3-(4,5)-dimethylthiahiazo (-z-yl)-3,5-di-phenytetrazoliumromide (MTT) assays. For cell migration and invasion assays, we used Transwell containing insert filter and Matrigel to imitate the in vivo environment. To examine whether both proteins were capable of interrupting the angiogenesis in vivo, we used the chick chicken embryonic chorioallantoic membrane (CAM) as an angiogenesis model. We used Integrin-linked kinase1 (ILK1) ELISA method to study functionary mechanisms of rLj-RGD3 and rLj-112. Both rLj-RGD3 and rLj-112 inhibited bFGF-induced proliferation of ECV304 cells in a dose-dependent manner with IC50 at 0.889 micromol/L and 0.160 micromol/L, respectively. The results of migration and invasion assays revealed that both rLj-RGD3 and rLj-112 showed significant inhibition on bFGF induced migration and invasion of ECV304; and rLj-112 was more active than rLj-RGD3. The result of CAM angiogenesis assay demonstrated that both proteins inhibited the angiogenesis in chick CAM, and rLj-112 was more active than rLj-RGD3. ELISA assay of ILK1 showed that both rLj-RGD3 and rLj-112 down-regulated ILK1 expression of ECV304 cell. The fact of rLj-112 was more active than rLj-RGD3 on anti-angiogenesis indicate that rLj-112 was likely with histidine-rich glycoprotein (HRG), and the factor of sequence homologous between rLj-RGD3 and HRG cannot enhance antiangiogenic activities of rLj-RGD3, the signal pathway of anti-angiogenesis of rLj-RGD3 and rLj-112 are differently.
Amino Acid Sequence ; Angiogenesis Inhibitors ; pharmacology ; Animals ; Base Sequence ; Cell Line ; Fish Venoms ; biosynthesis ; genetics ; isolation & purification ; pharmacology ; Humans ; Lampreys ; metabolism ; Molecular Sequence Data ; Mutant Proteins ; chemistry ; pharmacology ; Oligopeptides ; biosynthesis ; genetics ; isolation & purification ; pharmacology

OBJECTIVETo observe the effect of human vascular endothelial growth factor (VEGF) fragment (3 approximately 4 exon) in E. coli on anti-angiogenesis.

METHODSThrough RT-PCR amplification, endonuclease cut and DNA sequence analysis identification, hVEGF fragment cDNA was inserted into E. coli expression vector pTrcHis2A. The prokaryotic expression plasmid pTrcHis2A/VEGF(3 approximately 4) was constructed and transformed into TOP10F.

RESULTSAfter 8hr isopropy-beta-D-thiogalactoside (IPTG) induction, VEGF fragment was expressed in 15% of total proteins through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The expressed protein was highly antigenic and specific. The VEGF fragment was further purified by affinity, which could inhibit HUVEC proliferation and neovascularization of the chick chorioallantoic membrane.

CONCLUSIONVEGF fragment is anti-angiogenetic, which may potentially be used in oncologico-biological targeting therapy.

Angiogenesis Inhibitors ; isolation & purification ; pharmacology ; Cloning, Molecular ; Endothelial Growth Factors ; genetics ; isolation & purification ; pharmacology ; Escherichia coli ; genetics ; Gene Expression ; drug effects ; Genetic Vectors ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; isolation & purification ; pharmacology ; Isopropyl Thiogalactoside ; pharmacology ; Lymphokines ; genetics ; isolation & purification ; pharmacology ; Peptide Fragments ; genetics ; isolation & purification ; pharmacology ; Plasmids ; genetics ; Polymerase Chain Reaction ; Vascular Endothelial Growth Factor A ; Vascular Endothelial Growth Factors

AIMTo investigate the chemical constituents of the rhizomes of Beesia calthaefolia native to China in order to obtain a more comprehensive understanding of its effective components.

METHODSCompounds were isolated by column chromatography with silica gel. Their structures were elucidated by spectral analysis and chemical evidence. Compounds identified were subjected to pharmacological evaluation.

RESULTSTwo novel compounds were isolated and identified as (20S, 24S)-15 alpha-acetoxy-16 beta, 24; 20, 24-diepoxy-9, 19-cyclolanostane-3 beta, 25-diol-3-O-beta-D-xylopyranoside (I) and (20S, 24R)-15 alpha-acetoxy-9, 19-cyclolanostane-3 beta, 16 beta, 20, 24, 25-pentaol-3-O-beta-D-xylopyranoside (II), named beesioside O and beesioside P.

CONCLUSIONCompounds I and II are new compounds. Compounds I exhibited immunosuppressive activity and could inhibit angiogenesis as well as inhibit the proliferation of osteoblast. Compound II displayed remarkable inhibition activity against calcium channel receptor.

Angiogenesis Inhibitors ; chemistry ; pharmacology ; Animals ; Calcium Channel Blockers ; chemistry ; pharmacology ; Immunosuppressive Agents ; chemistry ; pharmacology ; Mice ; Molecular Conformation ; Molecular Structure ; Plants, Medicinal ; chemistry ; Ranunculaceae ; chemistry ; Saponins ; chemistry ; isolation & purification ; pharmacology

To explore the effects of protocatechuic acid (PCA) and its derivants on angiogenesis of the chick embryo chorioallantoic membrane (CAM) and scavenging DPPH radical in vitro. The protection of benzyl and alkaline hydrolysis of benzyl ester were employed. The structures of PCA-1, PCA-2 and PCA-3, the derivates of PCA, were elucidated by 1H, 13C-NMR and MS data The bioactivity of PCA and its derivants was evaluated on the models of DPPH radical and chick embryo chorioallantoic membrane (CAM), respectively. PCA and PCA-1 showed the best activity of scavenging DPPH radical among all the compounds. In contrast to PCA-2, PCA and PCA-3 displayed inhibition to angiogenesis (P < 0.001). Pyrocatechol hydroxyl is the active site of PCA on scavenging DPPH radical in vitro. PCA with carboxyl and without pyrocatechol hydroxyl seems to show promotion to angiogenesis, but it needs more evidences.
Angiogenesis Inducing Agents ; antagonists & inhibitors ; chemistry ; Animals ; Biphenyl Compounds ; Catechols ; chemistry ; Chick Embryo ; Chorioallantoic Membrane ; drug effects ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Free Radical Scavengers ; chemistry ; Hydroxybenzoates ; chemistry ; Magnetic Resonance Spectroscopy ; Molecular Structure ; Picrates

In the course of screening of angiogenesis inhibitor from natural products, cryptotanshinone from Salvia miltiorrhiza was isolated as a potent small molecule inhibitor of angiogenesis. Cryptotanshinone inhibits bFGF-induced angiogenesis of BAECs at ten micromolar ranges in vitro without cytotoxicity. Tanshinone IIA, another tanshinone isolated from S. miltiorrhiza, which is structurally very similar to cryptotanshinone except C-15 position of dihydrofuran ring does not inhibit angiogenesis induced by bFGF. These results demonstrate that cryptotanshinone is a new anti-angiogenic agent and double bond at C-15 position of the dihydrofuran ring plays a crucial role in the activity.
Angiogenesis Inhibitors/chemistry/isolation & purification/*pharmacology ; Animals ; Cattle ; Cell Movement/drug effects ; Cell Proliferation/drug effects ; Cells, Cultured ; Drugs, Chinese Herbal/chemistry/isolation & purification/pharmacology ; Endothelial Cells/drug effects/physiology ; Fibroblast Growth Factor 2/pharmacology ; Humans ; Neovascularization, Physiologic/drug effects ; Phenanthrenes/chemistry/isolation & purification/*pharmacology ; Plant Roots/chemistry ; Research Support, Non-U.S. Gov't ; Salvia miltiorrhiza/*chemistry

Angiostatin(AS) and endostatin(ES) are both potent endogenous angiogenesis inhibitors, and the combination of AS and ES has been shown to have synergistic antiangiogenic effects. Here we report the fusion protein AS-ES expressed in E. coli which has antiangiogenic effects. At first, AS and ES genes were cloned respectively through RT-PCR, then fusion gene was made through gene splicing ,finally pET-42 (b)/AS-ES expression plasmid was constructed and transduced in E. coli BL21 (DE3). Target protein was in form of inclusion body,the rate of expression was about 14%, and MW about 65KD. Western blotting assay showed expressed protein had specific immune reaction to both the antibodies of AS and ES. The expressed protein which was refolded and purified through heparin affinity chromatography had antiangiogenic effect to vessels on chicken embryo chorioallantoic membrane. The results show that fusion protein AS-ES was expressed successfully in E. coli, and the expressed protein,which was renatured and purified, had immuno-reactivity to anti-AS and anti-ES in Western blotting and angiogenesis inhibition activity.
Angiogenesis Inhibitors ; Angiostatins ; biosynthesis ; genetics ; isolation & purification ; pharmacology ; Animals ; Blotting, Western ; Chick Embryo ; Endostatins ; biosynthesis ; genetics ; isolation & purification ; pharmacology ; Escherichia coli ; genetics ; metabolism ; Plasmids ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; isolation & purification ; pharmacology ; Recombination, Genetic ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection

Both the morbidity and mortality of ovarian cancer, among malignant tumors ot temale genital organs, are quite high. The traditional therapeutic methods on ovarian cancer are surgical operation, chemotherapy, radiotherapy and combination of these methods mentioned above. In recent years, some components of traditional Chinese medicine, such as genistein, semen Coicis, phytosterols, curcumin, quercetin, ginsenoside, etc. have been found to exert anticancer actions of inhibiting proliferation and inducing apoptosis of cancer cells, increasing the sensitivity of patients to chemotherapeutic agents in viva and/or in vitro, the mechanisms involve such aspects as inhibiting activity of key enzymes in cell metabolism, affecting gene expression, antioxidation, and inhibiting tumor angiogenesis, etc. As an adjuvant therapeutic means, the bioactive components of traditional Chinese medicine have broad future of clinical application.
Angiogenesis Inhibitors ; pharmacology ; Animals ; Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Curcumin ; isolation & purification ; pharmacology ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Female ; Genistein ; isolation & purification ; pharmacology ; Humans ; Ovarian Neoplasms ; blood supply ; pathology ; Quercetin ; isolation & purification ; pharmacology ; Tumor Cells, Cultured

AIMTo investigate the inhibitory effects of artesunate on angiogenesis.

METHODSThe in vitro anti-angiogenic effect of artesunate was tested on models of angiogenesis: proliferation, migration and tube formation of human umbilical vein endothelial (HUVE) cells; The anti-angiogenic effect in vivo was evaluated in nude mice by means of human ovarian cancer HO-8910 implantation and immunohistochemical stainings for microvessel (CD31), vascular endothelial growth factor (VEGF) and VEGF receptor KDR/flk-1.

RESULTSArtesunate significantly inhibited angiogenesis in a concentration-dependent form in range of 0.5-50 mumol.L-1. The IC50 of artesunate for HUVE cells was (21 +/- 3) mumol.L-1. Growth of xenograft tumor was decreased and microvessel density was reduced following drug-treatment with no apparent toxicity to the animals. Artesunate also remarkably lowered VEGF expression on tumor cells and KDR/flk-1 expression on endothelial cells as well as tumor cells.

CONCLUSIONArtesunate was shown to inhibit angiogenesis in vitro and in vivo. These findings together with the known low toxicity of artesunate are clues that artesunate may be a promising angiogenesis inhibitor.

Angiogenesis Inhibitors ; pharmacology ; Animals ; Artemisia ; chemistry ; Artemisinins ; isolation & purification ; pharmacology ; Endothelial Cells ; cytology ; Female ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Ovarian Neoplasms ; metabolism ; pathology ; Receptors, Vascular Endothelial Growth Factor ; biosynthesis ; Sesquiterpenes ; isolation & purification ; pharmacology ; Tumor Cells, Cultured ; Umbilical Veins ; cytology ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis

Bibenzyl is a type of active compounds abundant in Dendrobium. In the present study, we investigated the inhibitory effects of six bibenzyls isolated from Dendrobium species on vascular endothelial growth factor (VEGF)-induced tube formation in human umbilical vascular endothelial cells (HUVECs). All those bibenzyls inhibited VEGF-induced tube formation at 10 micromol x L(-1) except tristin, and of which moscatilin was found to have the strongest activity at the same concentration. The lowest effective concentration of moscatilin was 1 micromol x L(-1). Further results showed that moscatilin inhibited VEGF-induced capillary-like tube formation on HUVECs in a concentration-dependent manner. Western blotting results showed that moscatilin also inhibited VEGF-induced phosphorylation of VEGFR2 (Flk-1/KDR) and extracellular signal-regulated kinase 1/2 (ERK1/2). Further results showed that moscatilin inhibited VEGF-induced activation of c-Raf and MEK1/2, which are both upstream signals of ERK1/2. Taken together, results presented here demonstrated that moscatilin inhibited angiogenesis via blocking the activation of VEGFR2 (Flk-1/KDR) and c-Raf-MEK1/2-ERK1/2 signals.
Angiogenesis Inhibitors ; administration & dosage ; isolation & purification ; pharmacology ; Animals ; Benzyl Compounds ; administration & dosage ; isolation & purification ; pharmacology ; Bibenzyls ; isolation & purification ; pharmacology ; Cell Count ; Cells, Cultured ; Dendrobium ; chemistry ; Dose-Response Relationship, Drug ; Human Umbilical Vein Endothelial Cells ; Humans ; MAP Kinase Kinase 1 ; metabolism ; MAP Kinase Kinase 2 ; metabolism ; MAP Kinase Signaling System ; drug effects ; Mice ; Mice, Inbred C57BL ; Neovascularization, Physiologic ; drug effects ; Phosphorylation ; drug effects ; Plants, Medicinal ; chemistry ; Proto-Oncogene Proteins c-raf ; metabolism ; Signal Transduction ; drug effects ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism