Amount Of Fibroblast Growth Factor Research Articles

The enhancing effects of heparin on the biological activity of FGF-2 in heparin−FGF-2−calcium phosphate composite layers

Orthopedic and dental implants coated with fibroblast growth factor-2 (FGF-2)−calcium phosphate composite layers promote dermis formation, bone formation, and angiogenesis because of the biological activity of FGF-2. Enhancing the biological activity of FGF-2 in the composite layers is important for its wider application in orthopedics and dentistry. This study incorporated low-molecular-weight heparin (LMWH) into the FGF-2−calcium phosphate composite layers and clarified the enhancing effects of LMWH on the biological activity of FGF-2 in the composite layers in vitro. LMWH−FGF-2−calcium phosphate composite layers were successfully formed on zirconia in supersaturated calcium phosphate solutions. The composite layers comprised continuous and macroscopically homogeneous layers and particles smaller than 500 nm in size composed of amorphous calcium phosphate. The amounts of Ca and P deposited on zirconia remained almost unchanged with the addition of LMWH under the presence of FGF-2 in the supersaturated calcium phosphate solution. The LMWH in the supersaturated calcium phosphate solution increased the stability of FGF-2 in the solution and the amount of FGF-2 in the composite layers. The LMWH in the composite layers increased the mitogenic and endothelial tube-forming activities of FGF-2, and FGF-2 activity of inducing osteogenic differentiation gene expression pattern in the composite layers. Our results indicate that the enhanced biological activity of FGF-2 in the LMWH−FGF-2−calcium phosphate composite layers is attributed to an LMWH-mediated increase in the amount of FGF-2, which maintains its biological activity in the supersaturated calcium phosphate solution and the composite layers. The LMWH−FGF-2−calcium phosphate composite layer is a promising coating for orthopedic and dental implants. Statement of significanceOrthopedic and dental implants coated with fibroblast growth factor-2 (FGF-2)−calcium phosphate composite layers promote dermis formation, bone formation, and angiogenesis because of the biological activity of FGF-2. Enhancing the biological activity of FGF-2 in the layers is important for wider its application in orthopedics and dentistry. This study demonstrates the enhancing effects of low-molecular-weight heparin (LMWH) contained within LMWH−FGF-2−calcium phosphate composite layers on the biological activity of FGF-2 in vitro. Our results indicate that the enhanced biological activity of FGF-2 within the composite layers arises from an LMWH-mediated increase in the amount of FGF-2, which maintains its biological activity in the LMWH−FGF-2−calcium phosphate composite layers and supersaturated calcium phosphate solutions used for coating the composite layers.

Effect of Histatin-1 Proteins to Fibroblasts Growth Factor-2 (FGF2) Concentrate and Fibroblasts Cell Migration on Human Gingival Fibroblast (HGF) Culture

The purpose of this study is to determine the effect of histatin-1 protein increasing the concentration of fibroblast growth factor (FGF2) and fibroblast cell migration in human gingival fibroblast (HGF) culture. The HGF cell culture used was obtained from odontectomy patients and was the result of the 4th passage. Cell culture was divided into 4 groups: HGF control group (without treatment) and treatment groups with 5µM, 10µM, and 20µM concentration of histatin-1 respectively. The amount of fibroblast growth factor 2 (FGF2) was quantified by using ELISA method. In vitro fibroblast cells migration was measured using scratch/wound healing assay method. FGF2 concentration and HGF cell migration were measured at hour 0, 3, 11, 24, and 48. The results of the One Way Anova statistical test difference between FGF 2 (ΔFGF2) at hour 24 showed a value of P = 0.042 (P≤0.05) and HGF cell migration at hour 11 showed a P value = 0.003 (P≤0.05). The conclusion of this study is that Histatin-1 Protein is able to increase the concentration of Fibroblast Growth Factor 2 (FGF2) and the migration of Human Gingival Fibroblast cells.

High MUC2 Mucin Biosynthesis in Goblet Cells Impedes Restitution and Wound Healing by Elevating Endoplasmic Reticulum Stress and Altered Production of Growth Factors

Intestinal epithelial cell wound healing involves cell migration, proliferation, and differentiation. Although numerous studies have analyzed the migration of absorptive epithelial cells during wound healing, it remains unclear how goblet cells restitute and how MUC2 mucin production affects this process. In this study, we examined the role of high MUC2 production in goblet cell migration during wound healing and demonstrated that during high MUC2 output, goblet cells migrated slower because of impaired production of wound healing factors and endoplasmic reticulum (ER) stress. Two goblet cell lines, HT29-H and HT29-L, that produced high and low MUC2 mucin, respectively, were used. HT29-L healed wounds faster than HT29-H cells by producing significantly higher amounts of fibroblast growth factor (FGF) 1, FGF2, vascular endothelial growth factor-C, and matrix metallopeptidase 1. Predictably, treatment of HT29-H cells with recombinant FGF2 significantly enhanced migration and wound healing. High MUC2 biosynthesis in HT29-H cells induced ER stress and delayed migration that was abrogated by inhibiting ER stress with tauroursodeoxycholic acid and IL-22. FGF2- and IL-22-induced wound repair was dependent on STAT1 and STAT3 signaling. During wound healing after dextran sulfate sodium-induced colitis, restitution of Math1M1GFP+ goblet cells occurred earlier in the proximal colon, followed by the middle and then distal colon, where ulceration was severe. We conclude that high MUC2 output during colitis impairs goblet cell migration and wound healing by reducing production of growth factorscritical in wound repair.

Inhibition of PAI-1 induces neutrophil-driven neoangiogenesis and promotes tissue regeneration via production of angiocrine factors in mice

AbstractPlasminogen activator inhibitor-1 (PAI-1), an endogenous inhibitor of a major fibrinolytic factor, tissue-type plasminogen activator, can both promote and inhibit angiogenesis. However, the physiologic role and the precise mechanisms underlying the angiogenic effects of PAI-1 remain unclear. In the present study, we report that pharmacologic inhibition of PAI-1 promoted angiogenesis and prevented tissue necrosis in a mouse model of hind-limb ischemia. Improved tissue regeneration was due to an expansion of circulating and tissue-resident granulocyte-1 marker (Gr-1+) neutrophils and to increased release of the angiogenic factor VEGF-A, the hematopoietic growth factor kit ligand, and G-CSF. Immunohistochemical analysis indicated increased amounts of fibroblast growth factor-2 (FGF-2) in ischemic gastrocnemius muscle tissues of PAI-1 inhibitor-treated animals. Ab neutralization and genetic knockout studies indicated that both the improved tissue regeneration and the increase in circulating and ischemic tissue-resident Gr-1+ neutrophils depended on the activation of tissue-type plasminogen activator and matrix metalloproteinase-9 and on VEGF-A and FGF-2. These results suggest that pharmacologic PAI-1 inhibition activates the proangiogenic FGF-2 and VEGF-A pathways, which orchestrates neutrophil-driven angiogenesis and induces cell-driven revascularization and is therefore a potential therapy for ischemic diseases.

Platelet gel from cord blood: A novel tool for tissue engineering

Recent findings show that growth factors (GF) play a relevant role in regenerative medicine. Platelets (PLT) may be used as “drug-stores” of GF that can be released upon activation by PLT granules. In this context, PLT gel (PG) from peripheral blood is currently used to improve tissue healing in orthopedic, oral maxillofacial and dermatologic surgery. Recent findings on multiple biological properties of human umbilical cord blood (CB) and its high level of viral safety prompted us to investigate the characteristics of its PLTs and the possibility to produce PLT gel from cord blood. Our study shows that CB PG releases high levels of vascular endothelial growth factor (VEGF) and platelet-derived growth factor-BB (PDGF-BB), substantial amounts of fibroblast growth factor (FGF), hepatocyte growth factor (HGF) and transforming growth factor-beta 1 (TGFbeta1), and minimal amounts of PDGF-AB. These findings suggest that CB PG can be a preferable tool for tissue engineering applications where high levels of VEGF and PDGF may be desirable.

Exogenously Added Fibroblast Growth Factor 2 (FGF-2) to NIH3T3 CellsInteracts with Nuclear Ribosomal S6 Kinase 2 (RSK2) in a Cell Cycle-dependentManner

Fibroblast growth factor 2 (FGF-2) has been detected in the nuclei of many tissues and cell lines. Here we demonstrate that FGF-2 added exogenously to NIH3T3 cells enters the nucleus and interacts with the nuclear active 90-kDa ribosomal S6 kinase 2 (RSK2) in a cell cycle-dependent manner. By using purified proteins, FGF-2 is shown to directly interact through two separate domains with two RSK2 domains on both sides of the hydrophobic motif, namely the NH2-terminal kinase domain (residues 360-381) by amino acid Ser-117 and the COOH-terminal kinase domain (residues 388-400) by amino acids Leu-127 and Lys-128. Moreover, this interaction leads to maintenance of the sustained activation of RSK2 in G1 phase of the cell cycle. FGF-2 mutants (FGF-2 S117A, FGF-2 L127A, and FGF-2 K128A) that fail to interact in vitro with RSK2 fail to maintain a sustained RSK2 activity in vivo.

Role of a spatial distribution of IP3 receptors in the Ca2+ dynamics of the Xenopus embryo at the mid‐blastula transition stage

Periodic calcium activity correlates temporally with the onset of gene expression in the embryo, suggesting a causal relation between these two events. Calcium transients are elicited by the action of fibroblast growth factor (FGF) through the activation of phospholipase C. In this work, we present a reaction-diffusion model that extends our previous results on the generation of calcium oscillations for a single and two coupled blastomere cells to a meridian of the Xenopus embryo at the mid-blastula transition. In the model, all cells are subject to the same amount of FGF and contain the same concentration of intracellular components, except for the amount of IP(3) receptors (IP3R). A bell-shaped distribution of IP3R produces the correct shape of the calcium transients experimentally observed in the Xenopus blastula at stage 8 (mid-blastula transition stage). The model is also capable of predicting period and amplitude values close to the experimental values. In our model, calcium transients induce spatially localized ERK periodic transients that could activate specific nuclear genes, allowing for the regional differentiation of the cells in the zone under the influence of the calcium signal.

Evaluation of high‐pressure retrograde coronary venous delivery of FGF‐2 protein

Delivery of angiogenic factors to ischemic myocardium remains a practical challenge. We evaluated the efficiency and efficacy of delivery of fibroblast growth factor-2 (FGF-2) protein via high-pressure retrograde injection into the anterior interventricular vein (AIV) in a porcine model of chronic myocardial ischemia. Labeled FGF-2 protein was delivered to the myocardium of three pigs via the AIV and the left anterior descending (LAD) coronary artery in three others. At 1 hr, the amount of protein in the left ventricle and the LAD region was quantified. Copper stents were implanted in the LAD of 25 pigs, resulting in chronic myocardial ischemia. At 4 weeks, microsphere-derived myocardial blood flow was assessed at rest and during pacing. In eight pigs (AIV FGF), FGF-2 protein (6 microg/kg) was delivered via high-pressure retrograde injection into the AIV. Six pigs (intracoronary FGF) received the same amount of FGF-2 by intracoronary delivery. Five pigs (AIV saline) received a placebo injection into the AIV and six pigs (control) served as controls. Four weeks later, myocardial blood flow was reassessed. At 1 hr, significantly more FGF remained in the left ventricle (1.3 vs. 0.82 microg; P < 0.04) and in the LAD region (1.2 vs. 0.64 microg; P = 0.03) after AIV compared to intracoronary delivery. Four weeks after treatment, resting LAD blood flow (normalized to right ventricular flow) improved slightly in the AIV FGF and intracoronary FGF arms (1.32-1.37 for both; P = 0.11), while it decreased significantly in the AIV saline (1.32-1.23; P = 0.02) and the control arms (1.32-1.19; P = 0.0004). Pacing LAD blood flow decreased significantly in the control arm (1.30-1.23; P < 0.05), but did not change significantly in the other three arms. High-pressure retrograde injection into the AIV may represent an efficient and effective means for delivering angiogenic factors to ischemic myocardium.

Inducible expression of FGF2 by a rat oligodendrocyte precursor cell line promotes CNS myelination in vitro

Transplantation of glial cells into the central nervous system (CNS) may be a promising approach for the treatment of myelin disorders such as multiple sclerosis (MS). Myelination by transplantation of oligodendrocyte precursors has been obtained in different animal models of demyelination. A strategy to favor CNS remyelination is to enrich the lesioned areas in growth factors to stimulate the quiescent population of oligodendrocyte precursors. In this context, we have developed a genetically modified CG4 cell line (CG4-FGF2), which are able to release significant amounts of fibroblast growth factor 2 (FGF2) in a controlable fashion in vitro. The data presented here demonstrate that upon induction with Dox, CG4-FGF2 cells retain their capacity to differentiate in vitro. Additionally, we provide evidence that FGF2 release by engineered cells enhance proliferation and migration of cells of the oligodendrocyte lineage without preventing them to differentiate and myelinate axons in vitro.

Angiogenesis as a target in rheumatoid arthritis

A ngiogenesis, the growth of new blood vessels, is important in a variety of fibroproliferative disorders, such as diabetic retinopathy, psoriasis, tumour growth, and rheumatoid arthritis (RA). We and others...

Syndecan-3 Is a Selective Regulator of Chondrocyte Proliferation

Chondrocyte proliferation is important for skeletal development and growth, but the mechanisms regulating it are not completely clear. Previously, we showed that syndecan-3, a cell surface heparan sulfate proteoglycan, is expressed by proliferating chondrocytes in vivo and that proliferation of cultured chondrocytes in vitro is sensitive to heparitinase treatment. To further establish the link between syndecan-3 and chondrocyte proliferation, additional studies were carried out in vivo and in vitro. We found that the topographical location of proliferating chondrocytes in developing chick long bones changes with increasing embryonic age and that syndecan-3 gene expression changes in a comparable manner. For in vitro analysis, mitotically quiescent chondrocytes were exposed to increasing amounts of fibroblast growth factor-2 (FGF-2). Proliferation was stimulated by as much as 8-10-fold within 24 h; strikingly, this stimulation was significantly prevented when the cells were treated with both fibroblast growth factor-2 (FGF-2) and antibodies against syndecan-3 core protein. This neutralizing effect was dose-dependent and elicited a maximum of 50-60% inhibition. To establish specificity of neutralizing effect, cultured chondrocytes were exposed to FGF-2, insulin-like growth factor-1, or parathyroid hormone, all known mitogens for chondrocytes. The syndecan-3 antibodies interfered only with FGF-2 mitogenic action, but not that of insulin-like growth factor-1 or parathyroid hormone. Protein cross-linking experiments indicated that syndecan-3 is present in monomeric, dimeric, and oligomeric forms on the chondrocyte surface. In addition, molecular modeling indicated that contiguous syndecan-3 molecules might form stable complexes by parallel pairing of beta-sheet segments within the ectodomain of the core protein. In conclusion, the results suggest that syndecan-3 is a direct and selective regulator of the mitotic behavior of chondrocytes and its role may involve formation of dimeric/oligomeric structures on their cell surface.

Expression of fibroblast growth factor 1 is lower in breast cancer than in the normal human breast

We have measured the amount of fibroblast growth factor 1 (FGF-1) mRNA and protein in primary breast cancers and non-malignant breast tissue and have found greatly reduced levels in breast cancer compared with non-malignant tissue. A total of 116 breast cancers and 37 biopsies taken from non-malignant breast were compared for FGF-1 mRNA expression using reverse transcriptase-polymerase chain reaction (RT-PCR) and significantly lower levels were found in the cancer tissues (P < 0.001). These findings were confirmed at the protein level where four out of five breast cancers contained no detectable FGF-1 and a fifth cancer had a low level of FGF-1 compared with three samples from reduction mammoplasties. Similar results were obtained from breast cell lines in which 80% of cancer cell lines had very low levels of FGF-1, whereas all non-malignant breast cell lines contained higher levels of FGF-1. Immunohistochemical analysis indicated that FGF-1 was present in the luminal epithelial cells of the non-malignant breast but was absent from cancer cells. The decreased levels of FGF-1 in breast cancer may indicate that stimulation of cancer cells is resulting in down-regulation of FGF-1 expression or may implicate FGF-1 as a differentiation factor rather than a growth factor at its physiological concentration in the breast.

Fibroblast growth factor 2 is elevated in term maternal and cord serum and amniotic fluid in pregnancies complicated by diabetes: relationship to fetal and placental size.

We previously detected immunoreactive fibroblast growth factor 2 (FGF-2) in maternal and fetal circulations. Here, we determined whether the amounts of FGF-2 in term maternal serum, cord serum, and amniotic fluid were altered in pregnancies complicated by diabetes, as these are associated with a higher incidence of fetal macrosomia and increased placental size. Serum and amniotic fluid were collected at term from normal pregnancies (n = 17), women with pregestational insulin-dependent diabetes (n = 37; group A), patients with previously undiagnosed diabetes (n = 32; group B), women with gestational diabetes (n = 85; group C), and women with a milder form of glucose intolerance in pregnancy (n = 16; group D). Mean newborn weight and length, and placental weight did not significantly differ between normal and diabetic pregnancies, although the placental weight tended to be higher in the latter. However, 24% of the infants in group A and 19% in group B had a birth weight in excess of the 90th percentile. Levels of insulin in cord serum and amniotic fluid in groups A and B were significantly elevated compared to control values. FGF-2 was extracted from serum and amniotic fluid by heparin-Sepharose affinity chromatography and subjected to Western blot analysis or quantified by specific RIA. Western blot analysis of maternal serum, cord serum, and amniotic fluid from diabetic pregnant patients revealed, in each case, a single immunoreactive FGF-2 species of 18 kilodaltons; this was absent from nonpregnancy serum. In normal term pregnancies, the mean immunoreactive FGF-2 level in cord serum was 119 +/- 28 pmol/L, and that in amniotic fluid was 91 +/- 35 pmol/L. Values were significantly increased (2- to 4-fold) in both cord serum and amniotic fluid for all groups of diabetic patients. The mean FGF-2 level in normal term maternal serum was 104 +/- 24 pmol/L, and this was significantly increased in diabetic patients in groups B and C. The amount of FGF-2 in maternal serum showed a positive correlation with newborn weight and length, and placental weight (P < 0.05 or better, by Spearman rank correlation), and significant positive correlations also existed between the amounts of FGF-2 in cord serum and newborn or placental weight. The results suggest that the FGF-2 levels in maternal serum, cord serum, and amniotic fluid at term are elevated in pregnancies complicated by diabetes, and that the amounts of FGF-2 in maternal serum and cord serum are correlated with fetal and placental size.