The angiogenesis induced with neotype amphiphilic peptide containing Isoleucine-Lysine-Valine-Alanine-Valine (IKVAV) was explored in vivo. The peptide was self-assembled into hydrogel, confirmed using transmission electron microscopy (TEM). One millilitre of 10 mg/ml peptide (experiment group, EG) and 16.67% gelatin (control group, CG) were injected subcutaneously beside rat backbone. The systemic response and local skin were observed one week after injection. The specimens were harvested two weeks later and immunohistochemically examined for vascular endothelial growth factor (VEGF). TEM showed that hydrogel was composed of interconnected nanofibers. The inflammatory reaction and necrosis of local skins were not found one week after injection. Lots of capillary vessels with complete wall were found within self-assembled peptide hydrogel, with erythrocytes noted inside the vessels in EG; the capillary vessels or erythrocytes were not found in the gelatin in CG. The immunohistochemical detection revealed VEGF-positive cells in EG, which were not found in CG. The self-assembly hydrogel from IKVAV-containing peptide was able to induce the angiogenesis in vivo.
Animals ; Hydrogels ; pharmacology ; Laminin ; pharmacology ; Neovascularization, Physiologic ; drug effects ; Peptide Fragments ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Skin ; blood supply

OBJECTIVETo study the role of integrin alpha 6 in cell attachment, spread, survival/proliferation and differentiation of human hepatocellular carcinoma (HCC) BEL-7402 cells on various substrates by monoclonal antibody against the extracellular domain of alpha 6 subunit (IA6ED McAb).

METHODSThe effect of McAb on attachment and spread of BEL-7402 cells on LN or FN substrate was examined. MTT analysis was used to examine the cell survival/proliferation, gelatin zymography to the matrix metalloproteinases (MMPs) secreted by BEL-7402 cells, and microparticle immunoabsorbent kit to AFP secretion while the cells were cultured on LN-, FN- or Matrigel-coated substrates.

RESULTSThe cell attachment, spread and survival/proliferation were inhibited. Moreover importantly, the malignant cell dedifferentiation and abnormal differentiation on LN-coated substrate were also strongly inhibited by IA6ED McAb.

CONCLUSIONLN and integrin alpha 6 regulate human HCC cell phenotypes of survival/proliferation and differentiation. The phenotypes of dedifferentiation and abnormal differentiation can be reversed by blocking the interaction between integrin alpha 6 and LN using IA6ED McAb, which may lower metastatic potency of tumor cells.

Antibodies, Monoclonal ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; Cell Adhesion ; drug effects ; Humans ; Integrin alpha6 ; immunology ; physiology ; Laminin ; physiology ; Liver Neoplasms ; pathology ; Phenotype ; Receptors, Laminin ; physiology ; Tumor Cells, Cultured

In this study, Ti-O films were synthesized using magnetron sputtering, and were pretreated using NaOH solution for improving surface activity from hydroxyl. The laminin(LN) biomacromolecule was further immobilized to the surface through an anminosilane linker. The surface characteristics of these samples were analyzed by Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Atomic Force Microscopy and the contact angle method. Finally, human umbilical vein endothelial cells (HUVEC) were in vitro seeded to the modified and unmodified Ti-O films surface for evaluating the cell compatibility. Survey results suggested that the functional group of hydroxyl was presented onto Ti-O film surface after being pretreated, and laminin could be covalently immobilized to Ti-O film surface by anminosilane linker. The in vitro cell culture results reveal that the biological behaviors of ECs on biochemical modified Ti-O film surface are excellent. The adherence, growth and proliferation of ECs on laminin-immobilized surface were obviously improved when compared to control one. It implies that the laminin immobilizing is helpful to increasing the endothelialization of Ti-O films.
Cell Proliferation ; Cells, Cultured ; Coated Materials, Biocompatible ; pharmacology ; Endothelial Cells ; cytology ; Humans ; Immobilized Proteins ; Laminin ; chemistry ; Titanium ; chemistry ; pharmacology ; Umbilical Veins ; cytology

OBJECTIVETo explore the effects of fibrinogen(FG) and laminin(LN) in promoting the osteogenic differentiation of bone mesenchymal stem cells(BMSCs)in PEGDA scaffold.

METHODSAfter the rabbit BMSCs were isolated and cultured to passage 3. BMSCs were blended in PEGDA-FG or PEGDA-LN hydrogels and cultured for 7 days. The levels of osterix,osteopontin,osteocalcin,collagen 2,myocardin,PPARΓ,and integrins Α2,Α5,and Α6 in PEGDA-FG and PEGDA-LN constructs were determined. Immunohistochemistry was used to detect the expressions of myocardin,PPARΓ,and OPN in PEGDA-FG and PEGDA-LN constructs.

RESULTSThe expressions of osterix,OPN,and OC were significantly higher in PEGDA-FG scaffold than day 0(all P<0.05). The OPN and OC expression levels were significantly higher in PEGDA-LN scaffold than day 0(both P<0.05). In PEGDA-FG and PEGDA-LN scaffold,myocardin,PPARΓ and COL 2 expression level showed no significant differences than day 0(all P>0.05). Integrin Α2 was upregulated in PEGDA-LN scaffold than day 0(P<0.05). Integrin Α6 was upregulated in PEGDA-FG scaffold than day 0(P<0.05). Immunohistochemistry stain showed that OPN expression increased in PEGDA-FG and PEGDA-LN scaffolds.

CONCLUSIONFG and LN can promote rabbit BMSCs osteogenic differentiation in PEGDA three-dimensional scaffold.

Animals ; Bone Marrow Cells ; cytology ; drug effects ; Cell Differentiation ; Cells, Cultured ; Fibrinogen ; pharmacology ; Laminin ; pharmacology ; Mesenchymal Stromal Cells ; cytology ; drug effects ; Osteogenesis ; drug effects ; Rabbits ; Tissue Scaffolds

OBJECTIVETo study the role of extracellular matrix (ECM) in neural differentiation of mouse embryonic stem cells (ESCs).

METHODSMouse ESCs were incubated in the ESC conditioned medium, and the formation of embryonic bodies (EBs) were induced in bacteriological dishes using high-concentration all-trans retinoic acid (RA). The EBs were seeded on different matrixes (gelatin, fibronectin, and laminin/poly-L-ornithine) to test their impact on neural differentiation of the ESCs using immunofluorescence assay. The effect of laminin/poly-L-ornithine on the growth of neurites was evaluated with fluorescence microscopy.

RESULTSHigh-concentration RA activated and accelerated the differentiation of ESCs toward nestin-positive neural progenitor cells. Fibronectin supplement in the matrix dose-dependently promoted ESC differentiation into neural progenitor cells, while laminin/poly-L-ornithine increased the growth of the neurites and induced the maturation of the differentiated neural cells.

CONCLUSIONECM plays an important role in neural differentiation of mouse ESCs, and application of FN produces the most conspicuous effect during the differentiation of the ESCs into the neural progenitor cells;laminin/poly-L-ornithine is the most effective during their differentiation into neural cells.

Animals ; Cell Differentiation ; drug effects ; Cells, Cultured ; Culture Media ; Embryonic Stem Cells ; cytology ; drug effects ; Extracellular Matrix ; physiology ; Fibronectins ; pharmacology ; Laminin ; pharmacology ; Mice ; Neurons ; cytology ; drug effects ; Peptides ; pharmacology ; Tretinoin ; pharmacology

OBJECTIVETo determine the effect of hypercholsterolemia induced by a high-lipid diet on glomerulosclerosis.

METHODSTwenty nephrotic syndrome (NS) Wistar rats administrated adriamycin (ADR) with a single intravenous dose of 5 mg/kg body weight, were divided into the standard and high-lipid chow groups. Another 20 weight-matched non-NS rats that received a vehicle alone were grouped as control. Urinary protein excretion and serum cholesterol were assayed; image analysis and techniques of pathology, immunohistochemistry, and molecular biology were used to determine morphological changes in glomeruli and the production of glomerular mesangial matrices in different groups.

RESULTSThe serum total cholesterol level was significantly higher in rats with high-lipid chow in both non-NS [(2.2 +/- 0.3) g/L vs. (0.9 +/- 0.1) g/L, P < 0.01] and NS [(9.5 +/- 0.2) g/L vs. (2.3 +/- 0.3) g/L, P < 0.01]. The urinary protein excretion was significantly higher in the high-lipid diet rats than in standard chow rats [(76.2 +/- 24.2) mg/24h vs. (44.8 +/- 13.6) mg/24h, P < 0.05] in NS rats. Although increases in the mesangial matrix and mesangial cells were observed in rats with high-lipid diet in both NS and non-NS group, more obvious pathological changes were found in NS group, such as lipid deposits and foam cell formation in mesangial areas, and progressing to focal and segmental glomerulosclerosis in some glomeruli. The immunohistochemical asay showed that the production of 3 major components (collagen IV, fibronectin, and laminin) was increased in NS group, especially in the rats with high-lipid chow. The increased expression of laminin mRNA was also detected with slot blotting in both NS and non-NS rats with high-lipid chow, and it was more obvious in the rats with NS.

CONCLUSIONOur findings indicated that diet-induced hyperlipidemia can lead to over-production of mesangial matrix components, and further aggravate glomerulosclerosis in ADR-induced nephrosis.

Animals ; Dietary Fats ; pharmacology ; Doxorubicin ; Fibronectins ; metabolism ; Glomerular Mesangium ; metabolism ; pathology ; Hypercholesterolemia ; metabolism ; Laminin ; metabolism ; Male ; Nephrotic Syndrome ; chemically induced ; metabolism ; pathology ; Proteinuria ; urine ; Rats ; Rats, Wistar

OBJECTIVETo investigate the effects of beta1-integrin, fibronectin (FN) and laminin (LN) on the invasive behavior of human gliomas.

METHODSFunctional impacts of beta1-integrin, fibronectin and laminin on cell adhesion, migration and metastasis of U251 malignant glioblastoma cells were investigated by in vitro adhesion, migration and invasion assays. The amount and distributions of cellular microfilaments and pseudopodia were studied by fluorescent cytochemistry, confocal laser scanning microscope and scanning electron microscope. Lastly, beta1-integrin, fibronectin and laminin were investigated for their roles in cellular microfilament skeleton.

RESULTS(1) Fibronectin did not affect cell adhesion of U251MG cells, but anti-beta1 integrin antibodies inhibited cell adhesion (P < 0.01); Laminin stimulated cell adhesion of U251MG cells (P < 0.01) but anti-beta1 integrin antibodies had little effect on the laminin-mediated cell adhesion. (2) The migration of U251MG cells on dishes coated with FN was inhibited by anti-beta1 integrin antibodies (P < 0.05). (3) F-actins formed strong and dense stress fibers in U251MG cells on dishes coated with FN and LN. Anti-beta1 integrin antibodies disrupted the microfilament network and F-actin aggregation. (4) FN and LN increased the number of pseudopodia on cell surface, whereas anti-beta1 integrin antibodies reversed this function. (5) FN and anti-beta1 integrin antibodies had little effects on the invasive ability of U251MG cells in vitro. The invasion was increased by LN, but inhibited by anti-beta1 integrin antibodies.

CONCLUSIONS(1) The interaction between beta1-integrin, FN may stimulate U251MG cell migration via changing the structures of microfilament skeleton and the number of pseudopodia. (2) beta1-integrin may play a role in the LN-mediated in vitro invasion of U251MG cells.

Cell Adhesion ; drug effects ; Cell Line, Tumor ; Cell Movement ; drug effects ; Fibronectins ; pharmacology ; Glial Fibrillary Acidic Protein ; analysis ; Glioma ; metabolism ; pathology ; ultrastructure ; Humans ; Immunohistochemistry ; Integrin beta1 ; pharmacology ; Laminin ; pharmacology ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Neoplasm Invasiveness

PURPOSE: Because previous studies have reported depleted antioxidant capacity in patients with chronic pancreatitis (CP), prevention of free radical production has gained importance in antifibrotic treatment strategies for CP. The aim of this study was to investigate the effects of ascorbic acid on oxidative capacity and pancreatic damage in experimental CP. MATERIALS AND METHODS: CP was induced in male Sprague-Dawley rats by infusion of dibutyltin dichloride (DBTC) into the tail vein. Ascorbic acid was given intraperitoneally at a daily dose of 10mg/kg body weight. The treatment groups were as follows: group 1, DBTC plus intraperitoneal physiologic saline; group 2, DBTC plus intraperitoneal ascorbic acid; group 3, solvent plus intraperitoneal physiologic saline; group 4, no operation plus intraperitoneal physiologic saline. Each group contained 15 animals. Treatment was started after CP was established. After 4 weeks of treatment, serum hyaluronic acid and laminin levels were determined by radioimmunoassay, pancreatic tissue oxidative stress was analyzed, and the degree of pancreatic damage was determined. RESULTS: Ascorbic acid treatment markedly increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) concentrations in pancreatic tissue (p < 0.01 for both). Significant serum hyaluronic acid and laminin reductions were observed in group 2 as compared with group 1 (p < 0.05). However, the serum hyaluronic acid and laminin levels remained elevated when compared with those of groups 3 and 4 (p < 0.05). Histopathologic scores were also lower in animals with CP that underwent ascorbic acid-treatment (p < 0.05). CONCLUSION: Ascorbic acid treatment alleviated the degree of oxidative stress and pancreatic damage in rat CP. Antioxidant treatment might be considered a potential option to improve the pathologic process in CP.
Animals ; Antioxidants/pharmacology ; Ascorbic Acid/*pharmacology ; Hyaluronic Acid/blood ; Laminin/blood ; Male ; Organotin Compounds ; Oxidative Stress/drug effects ; Pancreas/*drug effects/pathology ; Pancreatic Diseases/blood/chemically induced/*prevention & control ; Rats ; Rats, Sprague-Dawley

OBJECTIVEThis study aimed at investigating whether notoginsenoside R1 (R1), a unique saponin found in Panax notoginseng could promote angiogenic activity on human umbilical vein endothelial cells (HUVECs) and elucidate their potential molecular mechanisms. In addition, vascular restorative activities of R1 was assessed in a chemically-induced blood vessel loss model in zebrafish.

METHODSThe in vitro angiogenic effect of R1 was compared with other previously reported angiogenic saponins Rg1 and Re. The HUVECs proliferation in the presence of R1 was determined by cell proliferation kit II (XTT) assay. R1, Rg1 and Re-induced HUVECs invasion across polycarbonate membrane was stained with Hoechst-33342 and quantified microscopically. Tube formation assay using matrigelcoated wells was performed to evaluate the pro-angiogenic actions of R1. In order to understand the mechanism underlying the pro-angiogenic effect, various pathway inhibitors such as SU5416, wortmannin (wort) or L-Nω-nitro- L-arginine methyl ester hydrochloride (L-NAME), SH-6 were used to probe the possible involvement of signaling pathway in the R1 mediated HUVECs proliferation. In in vivo assays, zebrafish embryos at 21 hpf were pre-treated with vascular endothelial growth factor (VEGF) receptor kinase inhibitor II (VRI) for 3 h only and subsequently post-treated with R1 for 48 h, respectively. The intersegmental vessels (ISVs) in zebrafish were assessed for the restorative effect of R1 on defective blood vessels.

RESULTSR1 could stimulate the proliferation of HUVECs. In the chemoinvasion assay, R1 significantly increased the number of cross-membrane HUVECs. In addition, R1 markedly enhanced the tube formation ability of HUVECs. The proliferative effects of these saponins on HUVECs were effectively blocked by the addition of SU5416 (a VEGF-KDR/Flk-1 inhibitor). Similarly, pre-treatment with wort [a phosphatidylinositol 3-kinase (PI3K)-kinase inhibitor], L-NAME [an endothelial nitric oxide synthase (eNOS) inhibitor] or SH-6 (an Akt pathway inhibitor) significantly abrogated the R1 induced proliferation of HUVECs. In chemicallyinduced blood vessel loss model in zebrafish, R1 significantly rescue the damaged ISVs.

CONCLUSIONR1, similar to Rg1 and Re, had been showed pro-angiogenic action, possibly via the activation of the VEGF-KDR/Flk-1 and PI3K-Akt-eNOS signaling pathways. Our findings also shed light on intriguing pro-angiogenic effect of R1 under deficient angiogenesis condition in a pharmacologic-induced blood vessels loss model in zebrafish. The present study in vivo and in vitro provided scientific evidence to explain the ethnomedical use of Panax notoginseng in the treatment of cardiovascular diseases, traumatic injuries and wound healing.

Animals ; Blood Vessels ; pathology ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Collagen ; pharmacology ; Disease Models, Animal ; Drug Combinations ; Ginsenosides ; chemistry ; pharmacology ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; enzymology ; physiology ; Humans ; Laminin ; pharmacology ; Neovascularization, Physiologic ; drug effects ; Phosphatidylinositol 3-Kinases ; metabolism ; Protein Kinase Inhibitors ; pharmacology ; Proteoglycans ; pharmacology ; Proto-Oncogene Proteins c-akt ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism ; Zebrafish

BACKGROUNDIn most colorectal carcinomas, the level of phospholipase C (PLC)-gamma 1 expression is greatly elevated. Increased expression of PLC-gamma 1 may play an important role in colon carcinogenesis, but the mechanism is not well known. The aim of this study was to evaluate the role of PLC-gamma 1 in colon carcinogenesis by using recombinant lentivirus that stably suppressed the PLC-gamma 1 expression in human colorectal carcinoma LoVo cells.

METHODSRecombinant lentivirus producing PLC-gamma 1 siRNA were prepared. After LoVo cells were transduced by each lentivirus, stably transduced cells were selected by Blasticidin. The protein and mRNA expression of PLC-gamma 1 were examined by Western-blot and reverse transcription-polymerase chain reaction (RT-PCR) analysis, and the effects of the lentivirus on the cell adhesion, migration and apoptosis were analyzed.

RESULTSStable LoVo cell line deficient in PLC-gamma 1, was established. Notably, PLC-gamma 1 was silenced without affecting the levels of other subtypes of PLC so that the role of PLC-gamma 1 in colon carcinogenesis could be examined. Silencing of endogenous PLC-gamma 1 resulted in efficient inhibition of the adhesion and migration of LoVo cells in vitro and a great increase of 5-fluorouracil induced apoptosis (30%-40%) of LoVo cells.

CONCLUSIONSPLC-gamma 1 may play an important role in metastasis and anti-apoptosis in human colorectal carcinomas.

Apoptosis ; drug effects ; Cell Adhesion ; Cell Line, Tumor ; Colorectal Neoplasms ; pathology ; therapy ; Fluorouracil ; pharmacology ; Humans ; Laminin ; antagonists & inhibitors ; genetics ; Lentivirus ; genetics ; Phospholipase C gamma ; antagonists & inhibitors ; genetics ; physiology ; RNA, Small Interfering ; therapeutic use