The changes of IGF binding proteins after rhGH administration to patients totally dependent on parenteral nutrition
GROWTH HORMONE & IGF RESEARCH
Authors: Justova, V; Lacinova, Z; Melenovsky, V; Marek, J; Holly, JMP; Haas, T
Abstract
The objective was to study the effect of recombinant human growth hormone (rhGH) administration to patients with chronic malnutrition maintained on total parenteral nutrition (TPN) on the levels of insulin-like growth factor-I (IGF-I) and IGF binding proteins (IGFBPs) during a double-blind trial. After 1 week of TPN the patients were randomized into group I (placebo) or group II (rhGH). Samples were collected on the first day (start of the TPN) to measure basal values, the seventh day to study the effect of TPN and the 10th, 14th and 21st days to evaluate the rhGH effect. Basal laboratory evaluation, nutritional status and glucose tolerance were assessed using standard laboratory techniques. Radioimmunoassays were used to analyse IGF-I, free IGF-I (flGF-I) and IGFBP1-3. Electrophoresis with Western ligand blotting and Western immunoblotting was applied to find the pattern of IGFBPs. TPN had no effect on the circulating IGF-I concentration and the pattern of IGFBPs present in the studied groups of patients. The rhGH administration led to significant increases of IGF-I, total IGFBP-3, glycosylated IGFBP-3 (39, 42 kDa) and the 29 kDa fragment of IGFBP-3 and the decrease of IGFBP-2 during the trial (P<0.05). The mean levels of IGFBP-I, flGF-I and the parameters of nutritional status in group II during the trial were not significantly influenced by rhGH. However, it has been found that IGFBP-I and flGF-I levels were correlated with the levels of the weekly nitrogen balance of each patient in group II at the end of the trial. In spite of the significant changes of IGF-I, IGFBP-2, total IGFBP-3 and IGFBP-3 (29 kDa proteolytic fragment) after rhGH administration to patients with malnutrition, maintained on parenteral nutrition, the increase of nitrogen balance was seen only in patients who decreased their IGFBP-I and increased bioavailable IGF-I as reflected by measurement of fIGF-I. The levels of IGFBP-I may provide a useful marker of IGF-I bioavailability in monitoring the efficiency of the rhGH therapy in malnourished patients. (C) 2001 Elsevier Science Ltd.
c-fos-induced growth factor/vascular endothelial growth factor D induces angiogenesis in vivo and in vitro
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Authors: Marconcini, L; Marchio, S; Morbidelli, L; Cartocci, E; Albini, A; Ziche, M; Bussolino, F; Oliviero, S
Abstract
c-fos-induced growth factor/vascular endothelial growth factor D (Figf/Vegf-D) is a secreted factor of the VEGF family that binds to the vessel and lymphatic receptors VEGFR-2 and VEGFR-3, Here,ve report that Figf/Vegf-D is a potent angiogenic factor in rabbit cornea in vivo in a dose-dependent manner. In vitro Figf/Vegf-D induces tyrosine phosphorylation of VEGFR-2 and VEGFR-3 in primary human umbilical cord vein endothelial cells (HUVECs) and in an immortal cell line derived from Kaposi's sarcoma lesion (KS-IMM). The treatment of HUVECs with Figf/Vegf-D induces dose-dependent cell growth. Figf/VEGF-D also induces HUVEC elongation and branching to form an extensive network of capillary-like cords in three-dimensional matrix. In KS-IMM cells Figf/Vegf-D treatment results in dose-dependent mitogenic and motogenic activities. Taken together with the previous observations that Figf/Vegf-D expression is under the control of the nuclear oncogene c-fos, our data uncover a link between a nuclear oncogene and angiogenesis, suggesting that Figf/Vegf-D may play a critical role in tumor cell growth and invasion.