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Moosa Mohammadi - One of the best experts on this subject based on the ideXlab platform.

  • Structural Biology of the FGF7 Subfamily.
    Frontiers in genetics, 2019
    Co-Authors: Allen Zinkle, Moosa Mohammadi
    Abstract:

    Mammalian fibroblast growth factor (FGF) signaling is intricately regulated via selective binding interactions between 18 FGF ligands and four FGF receptors (FGFR1-4), three of which (FGFR1-3) are expressed as either epithelial ("b") or mesenchymal ("c") splice isoforms. The FGF7 subfamily, consisting of FGF3, FGF7, FGF10, and FGF22, is unique among FGFs in that its members are secreted exclusively by the mesenchyme, and specifically activate the "b" isoforms of FGFR1 (FGFR1b) and FGFR2 (FGFR2b) present in the overlying epithelium. This unidirectional mesenchyme-to-epithelium signaling contributes to the development of essentially all organs, glands, and limbs. Structural analysis has shown that members of the FGF7 subfamily achieve their restricted specificity for FGFR1b/FGFR2b by engaging in specific contacts with two alternatively spliced loop regions in the immunoglobulin-like domain 3 (D3) of these receptors. Weak basal receptor-binding affinity further constrains the FGF7 subfamily's specificity for FGFR1b/2b. In this review, we elaborate on the structural determinants of FGF7 subfamily receptor-binding specificity, and discuss how affinity differences among the four members for the heparin sulfate (HS) co-receptor contribute to their disparate biological activities.

  • Molecular Mechanisms of Fibroblast Growth Factor Signaling in Physiology and Pathology
    Cold Spring Harbor Perspectives in Biology, 2013
    Co-Authors: Artur A. Belov, Moosa Mohammadi
    Abstract:

    Fibroblast growth factor (FGF) signaling fulfills essential roles in metazoan development and metabolism. A wealth of literature has documented the requirement for FGF signaling in multiple processes during embryogenesis, including implantation (Feldman et al. 1995), gastrulation (Sun et al. 1999), somitogenesis (Dubrulle and Pourquie 2004; Wahl et al. 2007; Lee et al. 2009; Naiche et al. 2011; Niwa et al. 2011), body plan formation (Martin 1998; Rodriguez Esteban et al. 1999; Tanaka et al. 2005; Mariani et al. 2008), morphogenesis (Metzger et al. 2008; Makarenkova et al. 2009), and organogenesis (Goldfarb 1996; Kato and Sekine 1999; Sekine et al. 1999; Sun et al. 1999; Colvin et al. 2001; Serls et al. 2005; Vega-Hernandez et al. 2011). Recent clinical and biochemical data have uncovered unexpected roles for FGF signaling in metabolic processes, including phosphate/vitamin D homeostasis (Consortium 2000; Razzaque and Lanske 2007; Nakatani et al. 2009; Gattineni et al. 2011; Kir et al. 2011), cholesterol/bile acid homeostasis (Yu et al. 2000a; Holt et al. 2003), and glucose/lipid metabolism (Fu et al. 2004; Moyers et al. 2007). Highlighting its diverse biology, deranged FGF signaling contributes to many human diseases, such as congenital craniosynostosis and dwarfism syndromes (Naski et al. 1996; Wilkie et al. 2002, 2005), Kallmann syndrome (Dode et al. 2003; Pitteloud et al. 2006a), hearing loss (Tekin et al. 2007, 2008), and renal phosphate wasting disorders (Shimada et al. 2001; White et al. 2001), as well as many acquired forms of cancers (Rand et al. 2005; Pollock et al. 2007; Gartside et al. 2009; di Martino et al. 2012). Endocrine FGFs have also been implicated in the progression of acquired metabolic disorders, including chronic kidney disease (Fliser et al. 2007), obesity (Inagaki et al. 2007; Moyers et al. 2007; Reinehr et al. 2012), and insulin resistance (Fu et al. 2004; Chen et al. 2008b; Chateau et al. 2010; Huang et al. 2011), giving rise to many opportunities for drug discovery in the field of FGF biology (Beenken and Mohammadi 2012). Based on sequence homology and phylogeny, the 18 mammalian FGFs are grouped into six subfamilies (Ornitz and Itoh 2001; Popovici et al. 2005; Itoh and Ornitz 2011). Five of these subfamilies act in a paracrine fashion, namely, the FGF1 subfamily (FGF1 and FGF2), the FGF4 subfamily (FGF4, FGF5, and FGF6), the FGF7 subfamily (FGF3, FGF7, FGF10, and FGF22), the FGF8 subfamily (FGF8, FGF17, and FGF18), and the FGF9 subfamily (FGF9, FGF16, and FGF20). In contrast, the FGF19 subfamily (FGF19, FGF21, and FGF23) signals in an endocrine manner (Beenken and Mohammadi 2012). FGFs exert their pleiotropic effects by binding and activating the FGF receptor (FGFR) subfamily of receptor tyrosine kinases that are coded by four genes (FGFR1, FGFR2, FGFR3, and FGFR4) in mammals (Johnson and Williams 1993; Mohammadi et al. 2005b). The extracellular domain of FGFRs consists of three immunoglobulin (Ig)-like domains (D1, D2, and D3), and the intracellular domain harbors the conserved tyrosine kinase domain flanked by the flexible amino-terminal juxtamembrane linker and carboxy-terminal tail (Lee et al. 1989; Dionne et al. 1991; Givol and Yayon 1992). A unique feature of FGFRs is the presence of a contiguous segment of glutamic and aspartic acids in the D1–D2 linker, termed the acid box (AB). The two-membrane proximal D2 and D3 and the intervening D2–D3 linker are necessary and sufficient for ligand binding/specificity (Dionne et al. 1990; Johnson et al. 1990), whereas D1 and the D1–D2 linker are implicated in receptor autoinhibition (Wang et al. 1995; Roghani and Moscatelli 2007; Kalinina et al. 2012). Alternative splicing and translational initiation further diversify both ligands and receptors. The amino-terminal regions of FGF8 and FGF17 can be differentially spliced to yield FGF8a, FGF8b, FGF8e, FGF8f (Gemel et al. 1996; Blunt et al. 1997), and FGF17a and FGF17b isoforms (Xu et al. 1999), whereas cytosine-thymine-guanine (CTG)-mediated translational initiation gives rise to multiple high molecular weight isoforms of FGF2 and FGF3 (Florkiewicz and Sommer 1989; Prats et al. 1989; Acland et al. 1990). The tissue-specific alternative splicing in D3 of FGFR1, FGFR2, and FGFR3 yields “b” and “c” receptor isoforms which, along with their temporal and spatial expression patterns, is the major regulator of FGF–FGFR specificity/promiscuity (Orr-Urtreger et al. 1993; Ornitz et al. 1996; Zhang et al. 2006). A large body of structural data on FGF–FGFR complexes has begun to reveal the intricate mechanisms by which different FGFs and FGFRs combine selectively to generate quantitatively and qualitatively different intracellular signals, culminating in distinct biological responses. In addition, these structural data have unveiled how pathogenic mutations hijack the normal physiological mechanisms of FGFR regulation to lead to pathogenesis. We will discuss the current state of the structural biology of the FGF–FGFR system, lessons learned from studying the mechanism of action of pathogenic mutations, and how the structural data are beginning to shape and advance the translational research.

  • plasticity in interactions of fibroblast growth factor 1 fgf1 n terminus with fgf receptors underlies promiscuity of fgf1
    Journal of Biological Chemistry, 2012
    Co-Authors: Andrew Beenken, Anna V Eliseenkova, Omar A Ibrahimi, Shaun K Olsen, Moosa Mohammadi
    Abstract:

    Abstract Tissue-specific alternative splicing in the second half of Ig-like domain 3 (D3) of fibroblast growth factor receptors 1–3 (FGFR1 to -3) generates epithelial FGFR1b-FGFR3b and mesenchymal FGFR1c-FGFR3c splice isoforms. This splicing event establishes a selectivity filter to restrict the ligand binding specificity of FGFRb and FGFRc isoforms to mesenchymally and epithelially derived fibroblast growth factors (FGFs), respectively. FGF1 is termed the “universal FGFR ligand” because it overrides this specificity barrier. To elucidate the molecular basis for FGF1 cross-reactivity with the “b” and “c” splice isoforms of FGFRs, we determined the first crystal structure of FGF1 in complex with an FGFRb isoform, FGFR2b, at 2.1 A resolution. Comparison of the FGF1-FGFR2b structure with the three previously published FGF1-FGFRc structures reveals that plasticity in the interactions of the N-terminal region of FGF1 with FGFR D3 is the main determinant of FGF1 cross-reactivity with both isoforms of FGFRs. In support of our structural data, we demonstrate that substitution of three N-terminal residues (Gly-19, His-25, and Phe-26) of FGF2 (a ligand that does not bind FGFR2b) for the corresponding residues of FGF1 (Phe-16, Asn-22, and Tyr-23) enables the FGF2 triple mutant to bind and activate FGFR2b. These findings taken together with our previous structural data on receptor binding specificity of FGF2, FGF8, and FGF10 conclusively show that sequence divergence at the N termini of FGFs is the primary regulator of the receptor binding specificity and promiscuity of FGFs.

  • The FGF family: biology, pathophysiology and therapy
    Nature Reviews Drug Discovery, 2009
    Co-Authors: Andrew Beenken, Moosa Mohammadi
    Abstract:

    Fibroblast growth factors (FGFs) signal through FGF receptor tyrosine kinases to regulate a wide range of biological processes during development and adulthood. FGF receptors (FGFRs) are involved in the pathogenesis of cancer and skeletal disorders. Experiments in model systems have shown that FGFR-specific inhibitors may be valuable in treating multiple myeloma, bladder and endometrial cancers. FGF1, FGF2 and FGF4 have been studied in clinical trials for the treatment of cardiovascular disease. The results of most of these trials have been unclear. However, some promising prospects remain. In particular, plasmids encoding FGF1 have shown potential in treating peripheral ischaemia. Recombinant FGF7 is Food and Drug Administration approved for the treatment of chemoradiation-induced oral mucositis. Research into the application of FGF7 to treat conditions such as graft-versus-host disease is ongoing. FGF18 increases cartilage formation in rats and may be useful in treating osteoarthritis. The endocrine FGF19 subfamily holds the greatest promise for therapeutic development. These ligands circulate throughout the body owing to weak affinity for HSGAG (heparan sulphate glycosaminoglycan), and they require α-klotho–β-klotho proteins as cofactors for their activity. The α-klotho–β-klotho proteins also determine the target-tissue specificity of FGF19 subfamily ligands. FGF19 negatively regulates bile acid synthesis and recombinant FGF19 increases the metabolic rate of mice. Unfortunately, FGF19 transgenic mice develop hepatocellular carcinomas, and this side effect may impede the pharmaceutical development of FGF19. FGF21 is a mediator of the fasting response that increases glucose uptake, improves insulin sensitivity and reduces serum glucagon and triglyceride levels. In contrast to FGF19, FGF21 is not mitogenic, and FGF21 administration leads to neither oedema nor hypoglycaemia, which are two common side effects of agents that modulate metabolic disorders. FGF21 thus shows great potential for treating type 2 diabetes. FGF23 reduces renal phosphate reabsorption and downregulates vitamin D activation. FGF23 is broadly implicated in human disease, including autosomal-dominant hypophosphataemic rickets, tumour-induced osteomalacia, familial tumoral calcinosis and end-stage kidney disease. Neutralizing antibodies against FGF23 have shown efficacy in model systems and demonstrate the clinical potential of FGF23-specific therapies. The family of fibroblast growth factors (FGFs) regulates a plethora of developmental processes, including brain patterning, branching morphogenesis and limb development. Several mitogenic, cytoprotective and angiogenic therapeutic applications of FGFs are already being explored, and the recent discovery of the crucial roles of the endocrine-acting FGF19 subfamily in bile acid, glucose and phosphate homeostasis has sparked renewed interest in the pharmacological potential of this family. This Review discusses traditional applications of recombinant FGFs and small-molecule FGF receptor kinase inhibitors in the treatment of cancer and cardiovascular disease and their emerging potential in the treatment of metabolic syndrome and hypophosphataemic diseases. The central roles of members of the fibroblast growth factor (FGF) family in human developmental processes and disease have been well documented. In their Review, Beenken and Mohammadi discuss the more established applications of FGF-related therapies in the treatment of cancer and cardiovascular disease, emphasizing their potential to modulate aspects of the metabolic syndrome and hypophosphataemic diseases.

  • impaired fgf signaling contributes to cleft lip and palate
    Proceedings of the National Academy of Sciences of the United States of America, 2007
    Co-Authors: Bridget M Riley, Moosa Mohammadi, Adela M Mansilla, Sandra Daackhirsch, Brion S Maher, Lisa M Raffensperger, Erilynn T Russo, A R Vieira, Catherine Dode, Mary L Marazita
    Abstract:

    Nonsyndromic cleft lip and palate (NS CLP) is a complex birth defect resulting from a combination of genetic and environmental factors. Several members of the FGF and FGFR families are expressed during craniofacial development and can rarely harbor mutations that result in human clefting syndromes. We hypothesized that disruptions in this pathway might also contribute to NS CLP. We sequenced the coding regions and performed association testing on 12 genes (FGFR1, FGFR2, FGFR3, FGF2, FGF3, FGF4, FGF7, FGF8, FGF9, FGF10, FGF18, and NUDT6) and used protein structure analyses to predict the function of amino acid variants. Seven likely disease-causing mutations were identified, including: one nonsense mutation (R609X) in FGFR1, a de novo missense mutation (D73H) in FGF8, and other missense variants in FGFR1, FGFR2, and FGFR3. Structural analysis of FGFR1, FGFR2, and FGF8 variants suggests that these mutations would impair the function of the proteins, albeit through different mechanisms. Genotyping of SNPs in the genes found associations between NS CLP and SNPs in FGF3, FGF7, FGF10, FGF18, and FGFR1. The data suggest that the FGF signaling pathway may contribute to as much as 3–5% of NS CLP and will be a consideration in the clinical management of CLP.

James A Thomson - One of the best experts on this subject based on the ideXlab platform.

Nobuyuki Itoh - One of the best experts on this subject based on the ideXlab platform.

  • Roles of FGF Signals in Heart Development, Health, and Disease.
    Frontiers in Cell and Developmental Biology, 2016
    Co-Authors: Nobuyuki Itoh, Yoshiaki Nakayama, Hiroya Ohta, Morichika Konishi
    Abstract:

    The heart provides the body with oxygen and nutrients and assists in the removal of metabolic waste through the blood vessels of the circulatory system. It is the first organ to form during embryonic morphogenesis. FGFs with diverse functions in development, health, and disease are signaling proteins, mostly as paracrine growth factors or endocrine hormones. The human/mouse FGF family comprises 22 members. Findings obtained from mouse models and human diseases with FGF signaling disorders have indicated that several FGFs are involved in heart development, health, and disease. Paracrine FGFs including FGF8, FGF9, FGF10, and FGF16 act as paracrine signals in embryonic heart development. In addition, paracrine FGFs including FGF2, FGF9, FGF10, and FGF16 play roles as paracrine signals in postnatal heart pathophysiology. Although FGF15/19, FGF21, and FGF23 are typical endocrine FGFs, they mainly function as paracrine signals in heart development or pathophysiology. In heart diseases, serum FGF15/19 levels or FGF21 and FGF23 levels decrease or increase, respectively, indicating their possible roles in heart pathophysiology. FGF2 and FGF10 also stimulate the cardiac differentiation of cultured stem cells and cardiac reprogramming of cultured fibroblasts. These findings provide new insights into the roles of FGF signaling in the heart and potential therapeutic strategies for cardiac disorders.

  • roles of fgfs as paracrine or endocrine signals in liver development health and disease
    Frontiers in Cell and Developmental Biology, 2016
    Co-Authors: Nobuyuki Itoh, Yoshiaki Nakayama, Morichika Konishi
    Abstract:

    The liver plays important roles in multiple processes including metabolism, the immune system, and detoxification and also has a unique capacity for regeneration. FGFs are growth factors that have diverse functions in development, health, and disease. The FGF family now comprises 22 members. Several FGFs have been shown to play roles as paracrine signals in liver development, health, and disease. FGF8 and FGF10 are involved in embryonic liver development, FGF7 and FGF9 in repair in response to liver injury, and FGF5, FGF8, FGF9, FGF17, and FGF18 in the development and progression of hepatocellular carcinoma. In contrast, FGF15/19 and FGF21 are endocrine signals. FGF15/19, which is produced in the ileum, is a negative regulator of bile acid metabolism and a stimulator of gallbladder filling. FGF15/19 is a postprandial, insulin-independent activator of hepatic protein and glycogen synthesis. It is also required for hepatocellular carcinoma and liver regeneration. FGF21 is a hepatokine produced in the liver. FGF21 regulates glucose and lipid metabolism in white adipose tissue. Serum FGF21 levels are elevated in non-alcoholic fatty liver. FGF21 also protects against non-alcoholic fatty liver. These findings provide new insights into roles of FGFs in the liver and potential therapeutic strategies for hepatic disorders.

  • Cardiac Fgf21 synthesis and release: an autocrine loop for boosting up antioxidant defenses in failing hearts
    Cardiovascular Research, 2015
    Co-Authors: Fabio Di Lisa, Nobuyuki Itoh
    Abstract:

    Fibroblast growth factors (Fgfs) are signalling proteins of ∼150–300 amino acids with diverse functions, mainly in development and metabolism. The human/mouse Fgf family comprises 22 members. Fgfs can be classified as intracellular, paracrine, and endocrine Fgfs by their action mechanisms. Among Fgfs, Fgf2, Fgf16, Fgf21, and Fgf23 have been shown to be cardiomyokines playing pathophysiological roles in the heart.1 Fgf2 and Fgf16 are paracrine Fgfs, which usually function in an autocrine/paracrine manner. In contrast, so far Fgf21 and Fgf23 have been reported to function in an endocrine manner. Cardiac Fgf2 promotes cardiac hypertrophy and fibrosis by activating MAPK signalling through the activation of Fgf receptor (Fgfr). In contrast, cardiac Fgf16 may prevent them by competing with Fgf2 for the binding site of Fgfr. Although Fgf23 is an endocrine Fgf, cardiac Fgf23 induces cardiac hypertrophy by activating calcineurin/NFAT signalling in an autocrine/paracrine manner.1 Fgf21 is usually known to be a hepatic hormone involved in the control of glucose, lipid, and energy metabolism. These actions of Fgf21 are mediated by activating MAPK signalling through the activation of Fgfr in an endocrine manner.2 Fgf21 is also produced in the heart and prevents cardiac hypertrophy by activating MAPK signalling through the activation of Fgfr.3 Cardiac Fgf21 expression is induced by the protein deacetylase Sirt1,3 which protects against hypertrophy, ischaemia–reperfusion injury, and oxidative stress in the …

  • Pathophysiological roles of FGF signaling in the heart
    Frontiers in Physiology, 2013
    Co-Authors: Nobuyuki Itoh, Hiroya Ohta
    Abstract:

    Cardiac remodeling progresses to heart failure, which represents a major cause of morbidity and mortality. Cardiomyokines, cardiac secreted proteins, may play roles in cardiac remodeling. Fibroblast growth factors (FGFs) are secreted proteins with diverse functions, mainly in development and metabolism. However, some FGFs play pathophysiological roles in cardiac remodelling as cardiomyokines. FGF2 promotes cardiac hypertrophy and fibrosis by activating MAPK signaling through the activation of FGF receptor (FGFR) 1c. In contrast, FGF16 may prevent these by competing with FGF2 for the binding site of FGFR1c. FGF21 prevents cardiac hypertrophy by activating MAPK signaling through the activation of FGFR1c with β-Klotho as a co-receptor. In contrast, FGF23 induces cardiac hypertrophy by activating calcineurin/NFAT signaling without αKlotho. These FGFs play crucial roles in cardiac remodeling via distinct action mechanisms. These findings provide new insights into the pathophysiological roles of FGFs in the heart and may provide potential therapeutic strategies for heart failure.

  • Hormone-like (endocrine) Fgfs: their evolutionary history and roles in development, metabolism, and disease
    Cell and Tissue Research, 2010
    Co-Authors: Nobuyuki Itoh
    Abstract:

    Fibroblast growth factors (Fgfs) are proteins with diverse functions in development, repair, and metabolism. The human Fgf gene family with 22 members can be classified into three groups, canonical, intracellular, and hormone-like Fgf genes. In contrast to canonical and intracellular Fgf s identified in invertebrates and vertebrates, hormone-like Fgf s , Fgf15/19 , Fgf21 , and Fgf23 , are vertebrate-specific. The ancestral gene of hormone-like Fgf s was generated from the ancestral gene of canonical Fgf s by gene duplication early in vertebrate evolution. Later, Fgf15/19 , Fgf21 , and Fgf23 were generated from the ancestral gene by genome duplication events. Canonical Fgfs act as autocrine/paracrine factors in an Fgf receptor (Fgfr)-dependent manner. In contrast, hormone-like Fgfs act as endocrine factors in an Fgfr-dependent manner. Canonical Fgfs have a heparin-binding site necessary for the stable binding of Fgfrs and local signaling. In contrast, hormone-like Fgf s acquired endocrine functions by reducing their heparin-binding affinity during their evolution. Fgf15/19 and Fgf23 require βKlotho and αKlotho as cofactors, respectively. However, Fgf21 might physiologically require neither. Hormone-like Fgfs play roles in metabolism at postnatal stages, although they also play roles in development at embryonic stages. Fgf15/19 regulates bile acid metabolism in the liver. Fgf21 regulates lipid metabolism in the white adipose tissue. Fgf23 regulates serum phosphate and active vitamin D levels. Fgf23 signaling disorders caused by hereditary diseases or tumors result in metabolic disorders. In addition, serum Fgf19 or Fgf21 levels are significantly increased by metabolic disorders. Hormone-like Fgfs are newly emerging and quite unique in their evolution and function.

Zipora Yablonkareuveni - One of the best experts on this subject based on the ideXlab platform.

  • gene expression patterns of the fibroblast growth factors and their receptors during myogenesis of rat satellite cells
    Journal of Histochemistry and Cytochemistry, 2000
    Co-Authors: Stefanie Kastner, Maria C Elias, Anthony J Rivera, Zipora Yablonkareuveni
    Abstract:

    Satellite cells are the myogenic precursors in postnatal muscle and are situated beneath the myofiber basement membrane. We previously showed that fibroblast growth factor 2 (FGF2, basic FGF) stimulates a greater number of satellite cells to enter the cell cycle but does not modify the overall schedule of a short proliferative phase and a rapid transition to the differentiated state as the satellite cells undergo myogenesis in isolated myofibers. In this study we investigated whether other members of the FGF family can maintain the proliferative state of the satellite cells in rat myofiber cultures. We show that FGF1, FGF4, and FGF6 (as well as hepatocyte growth factor, HGF) enhance satellite cell proliferation to a similar degree as that seen with FGF2, whereas FGF5 and FGF7 are ineffective. None of the growth factors prolongs the proliferative phase or delays the transition of the satellite cells to the differentiating, myogenin+ state. However, FGF6 retards the rapid exit of the cells from the myogenin...

Masashi Suzuki - One of the best experts on this subject based on the ideXlab platform.

  • a stable chimeric fibroblast growth factor fgf can successfully replace basic fgf in human pluripotent stem cell culture
    PLOS ONE, 2015
    Co-Authors: Yasuko Onuma, Toru Imamura, Masahiro Asada, Masashi Suzuki, Kumiko Higuchi, Yasuhiko Aiki, Yujing Shu, Makoto Asashima, Yuzuru Ito
    Abstract:

    Fibroblast growth factors (FGFs) are essential for maintaining self-renewal in human embryonic stem cells and induced pluripotent stem cells. Recombinant basic FGF (bFGF or FGF2) is conventionally used to culture pluripotent stem cells; however, because of the instability of bFGF, repeated addition of fresh bFGF into the culture medium is required in order to maintain its concentration. In this study, we demonstrate that a heat-stable chimeric variant of FGF, termed FGFC, can be successfully used for maintaining human pluripotent stem cells. FGFC is a chimeric protein composed of human FGF1 and FGF2 domains that exhibits higher thermal stability and protease resistance than do both FGF1 and FGF2. Both human embryonic stem cells and induced pluripotent stem cells were maintained in ordinary culture medium containing FGFC instead of FGF2. Comparison of cells grown in FGFC with those grown in conventional FGF2 media showed no significant differences in terms of the expression of pluripotency markers, global gene expression, karyotype, or differentiation potential in the three germ lineages. We therefore propose that FGFC may be an effective alternative to FGF2, for maintenance of human pluripotent stem cells.

  • comparison of expression profiles of several fibroblast growth factor receptors in the mouse jejunum suggestive evidence for a differential radioprotective effect among major fgf family members and the potency of fgf1
    Radiation Research, 2009
    Co-Authors: Akiko Hagiwara, Kaori Motomura, Masashi Suzuki
    Abstract:

    Abstract Hariwara, A., Nakayama, F., Motomura, K., Asada, M., Suzuki, M., Imamura, T. and Akashi, M. Comparison of Expression Profiles of Several Fibroblast Growth Factor Receptors in the Mouse Jejunum: Suggestive Evidence for a Differential Radioprotective Effect among Major FGF Family Members and the Potency of FGF1. Radiat. Res. 172, 58-65 (2009). Several members of the fibroblast growth factor (FGF) family have the potential to protect the intestine against the side effects of radiation therapy. FGF1 is capable of signaling through all subtypes of FGF receptors (FGFRs), whereas FGF7 and FGF10 activate only the epithelial-specific subtype, FGFR2IIIb (FGFR2b). The present study compared the protective activity of FGF1, FGF7 and FGF10 and examined the profiles of FGFR expression in the jejunum of BALB/c mice given total-body irradiation (TBI) with γ rays. TBI caused drastic increases in FGFR1–4 transcript levels in the jejunum. However, FGFR2b protein temporarily decreased at 12 and 24 h after irradiatio...

  • an fgf1 fgf2 chimeric growth factor exhibits universal fgf receptor specificity enhanced stability and augmented activity useful for epithelial proliferation and radioprotection
    Biochimica et Biophysica Acta, 2008
    Co-Authors: Kaori Motomura, Akiko Komikuramochi, Masashi Suzuki, Akiko Hagiwara, Yoshiro Hanyu, Emi Honda, Miho Kimura, Junko Oki, Masahiro Asada
    Abstract:

    Structural instability of wild-type fibroblast growth factor (FGF)-1 and its dependence on exogenous heparin for optimal activity diminishes its potential utility as a therapeutic agent. Here we evaluated FGFC, an FGF1:FGF2 chimeric protein, for its receptor affinity, absolute heparin-dependence, stability and potential clinical applicability. Using BaF3 transfectants overexpressing each FGF receptor (FGFR) subtype, we found that, like FGF1, FGFC activates all of the FGFR subtypes (i.e., FGFR1c, FGFR1b, FGFR2c, FGFR2b, FGFR3c, FGFR3b and FGFR4) in the presence of heparin. Moreover, FGFC activates FGFRs even in the absence of heparin. FGFC stimulated keratinocytes proliferation much more strongly than FGF2, as would be expected from its ability to activate FGFR2b. FGFC showed greater structural stability, biological activity and resistance to trypsinization, and less loss in solution than FGF1 or FGF2. When FGFC was intraperitoneally administered to BALB/c mice prior to whole body gamma-irradiation, survival of small intestine crypts was significantly enhanced, as compared to control mice. These results suggest that FGFC could be useful in a variety of clinical applications, including promotion of wound healing and protection against radiation-induced damage.

  • comprehensive analysis of fgf and fgfr expression in skin fgf18 is highly expressed in hair follicles and capable of inducing anagen from telogen stage hair follicles
    Journal of Investigative Dermatology, 2005
    Co-Authors: Mitsuko Kawano, Akiko Komikuramochi, Masashi Suzuki, Ju Jiang
    Abstract:

    We quantified the mRNA expression of all 22 fibroblast growth factor family members (FGF) and their four receptors (FGFR) in adult mouse full-thickness skin at various stages of the hair growth cycle. We found that in addition to mRNA encoding FGF previously identified in skin (FGF1, 2, 5, 7, 10, 13, and 22), FGF18 mRNA was also strongly expressed. Expression of these FGF varied throughout hair growth cycle: mRNA expression of FGF18 and 13 peaked at telogen; FGF7 and 10 at anagen V; and FGF5 and 22 at anagen VI. In situ hybridization revealed that FGF18 mRNA is mainly expressed in the anagen inner root sheath and telogen bulge of hair follicles. In culture, FGF18 stimulated DNA synthesis in human dermal fibroblasts, dermal papilla cells, epidermal keratinocytes and vascular endothelial cells. When FGF18 was administered subcutaneously to mice in a uniform telogen state, anagen hair growth was observed. Our findings suggest that FGF18 is important for the regulation of hair growth and the maintenance of skin in adult mice.