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Marine biodiversity as a new source of promising polysaccharides
Published in Antonio Trincone, Enzymatic Technologies for Marine Polysaccharides, 2019
Sylvia Colliec-Jouault, Corinne Sinquin, Agata Zykwinska, Christine Delbarre-Ladrat
Low-molecular-weight sulfated or oversulfated derivatives have been prepared from HE800 and GY785 EPS, respectively. LMW HE800 EPS and LMW GY785 EPS derivatives have been obtained by a free-radical depolymerization. Then a sulfation reaction has been developed using a chemical process to generate new bioactive derivatives having a molecular weight of <30,000/mol and a sulfate content of 30% w/w (Colliec-Jouault et al. 2001). HE800 EPS derivatives were potent inhibitors of the complement cascade and 10 times less anticoagulant than heparin in clotting assays. They improved the dermal fibroblast proliferation in two-dimensional (2D) cultures and were reported to inhibit interleukin-1beta (IL-1β) stimulation of matrix metalloproteinase (MMP) secretion. To summarize, these derivatives are able to inhibit some parameters involved in tissue breakdown and inflammation such as complement cascade and induction of MMP by IL-1β. They are also able to induce tissue repair by promoting fibroblast growth factor (FGF) activity and consequently fibroblast proliferation. HE800 EPS produced by Vibrio diabolicus and its derivatives can be considered potentially as new functional biomaterial for tissue repair and engineering (Senni et al. 2013).
Wound Healing and Inflammatory Response to Biomaterials
Published in Chih-Chang Chu, J. Anthony von Fraunhofer, Howard P. Greisler, Wound Closure Biomaterials and Devices, 2018
P. H. Lin, M. K. Hirko, J. A. von Fraunhofer, H. P. Greisler
Cellular proliferation at the implant site, which leads to both the wound healing as well as fibrous cap formation around the biomaterial, is predominantly a growth factor-mediated event. Macrophages add to this form of healing by secreting peptide growth factors such as platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), and transforming growth factor β (TGF-β).55–59 Secretion of these growth factors by activated macrophages will stimulate the growth of the endothelial cells, smooth muscle cells, and fibroblasts surrounding the biomaterial. PDGF is a potent mitogen for cells of mesenchymal origin, including smooth muscle cells and fibroblasts.60,61 Additionally, it is also chemotactic to monocytes62 and smooth muscle cells.63 FGF is mitogenic to endothelial cells, smooth muscle cells, and fibroblasts and is an important promoter and regulator of angiogenesis.58,64 While polymers such as Dacron®, ePTFE, and lactide/glycolide biopolymers stimulate the production of these growth factors,65,66–68 it is unclear whether there is a preferential production of a specific growth factor by a particular biomaterial. It is probable that the biochemical composition of a biomaterial along with its construction and physical characteristics, as well as the site of implantation, may modulate the relative synthetic activities of specific growth factors by macrophages.
Stem Cell Engineering Using Bioactive Molecules for Bone-Regenerative Medicine
Published in Gilson Khang, Handbook of Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine, 2017
The FGF family consists of 22 polypeptides (FGF1 to 22) with diverse biological activities. FGF-2 regulates a variety of cellular functions, including differentiation and proliferation, by binding to cell surface FGF receptors (FGFRs) in the presence of heparin proteoglycans.72 FGF-2 is known as a heparin-binding GF, but the localization of the heparin-binding site has not been fully investigated. Lee et al. examined two potential HBDs of FGF-2, residues 105 to 111 (F105, YKRSRYT) and 119 to 135 (F119, KRTGQYKLGSKTGPGQK).72 Among the motifs, both F105 and F119 interact with cell surface heparin sulfate proteoglycans and suggested that FGF-2 contains two heparin-binding sites. Additionally, osteoblast differentiation was increased by surface immobilization of F105 and F119 and was confirmed by ALP activity and mineralization assays. These heparin-binding peptides could be applied as biological agents in tissue regeneration tools, especially for bone regeneration, to enhance osteoblast differentiation and surface modification. A peptide sequence of FN consisting of WQPPRARI was immobilized onto polystyrene and polyethylene terephthalate film by the use of a heterobifunctional crosslinker. This peptide promoted endothelial cell attachment and spreading.73 This example demonstrates that the cell-binding activity of immobilized heparin-binding peptides may have significant applications in cell and tissue engineering research.
Natural latex serum: characterization and biocompatibility assessment using Galleria mellonella as an alternative in vivo model
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Giovana Sant’Ana Pegorin Brasil, Patrícia Pimentel de Barros, Matheus Carlos Romeiro Miranda, Natan Roberto de Barros, Juliana Campos Junqueira, Alejandro Gomez, Rondinelli Donizetti Herculano, Ricardo José de Mendonça
The fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) signaling system contains 22 members, which are responsible for regulating a variety of biological processes, including embryogenesis, angiogenesis, tissue homeostasis, wound repair and cancer. It has been observed in most studies that different members of the FGF family, mainly FGF1 and FGF2, can induce in vitro a complex pro-angiogenic phenotype in endothelial cells, which covers various aspects of angiogenesis in vivo, including from modulation of cell proliferation, migration, protease production, integrin and cadherin receptor expression, and intercellular gap junction communication [79, 80].
The role of rhFGF-2 soaked polymer membrane for enhancement of guided bone regeneration
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Sang-Hoon Lee, Young-Bum Park, Hong-Seok Moon, June-Sung Shim, Han-Sung Jung, Hyung Jun Kim, Moon-Kyu Chung
Much of the study on maximizing bone regeneration had been performed on growth factors, and in fact, growth factors play an important role in the development of teeth and surrounding tissues. Among them, Bone morphogenic protein (BMP) and Fibroblast growth factor (FGF) play an important role in bone development and fracture healing process that occur naturally in the body and their temporal and spatial manifestations are known to regulate the extent of limb growth and bone formation [6]. FGF is known to induce proliferation, chemotaxis, and angiogenesis of undifferentiated ectodermal cells and it is also known to act as an important regulator of periodontal ligament regeneration and bone formation in the body [7–10]. Also, in the absence of FGF-2 gene, both bone quality and quantity decreased [11]. Several studies using FGF-2 showed increased bone regeneration and new bone formation [4,12–15]. These studies show that FGF-2 plays an important role in bone regeneration in the body. FGF is the protein first found in bovine pituitary gland in 1974, which strongly induces proliferation of fibroblast [16]. The action of FGF-2 increases laminin mRNA expression, which is important for angiogenesis, and increases synthesis of Osteopontin, Hyaluronan. It also increases early osteogenic marker, Cbfa-1 [17–20]. Conversely, the synthesis of type I collagen and the synthesis of osteocalcin, a late osteogenic marker, are reduced. Alkaline phosphatase activity associated with osteogenic differentiation levels also decreases [17,18,21]. This phenomenon is interesting because FGF-2 increases the proliferation of immature mesenchymal cells, but also reduces the differentiation and matrix synthesis of osteoblastic cells. In other words, although not directly involved in osteogenesis, proliferation of immature mesenchymal cells is sufficiently achieved at the early stage of osteogenesis, resulting in an advantageous environment for continuous bone formation.