Selective receptor-mediated impairment of growth factor activity in neonatal- and X-linked adrenoleukodystrophy patients

2019 ◽  
Vol 32 (7) ◽  
pp. 733-738
Author(s):  
Mazen Al-Essa ◽  
Gursev S. Dhaunsi
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Dna Synthesis ◽  
Serum Levels ◽  
Vital Role ◽  
Brdu Incorporation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Factor Activity ◽  
Poor Growth ◽  
Fgf Receptor

Abstract Background Neonatal adrenoleukodystrophy (n-ALD) and X-linked ALD (X-ALD) patients present with demyelination, poor growth and progressive mental retardation. Growth factors are known to play a vital role in the development of children. Objective To examine the mitogenic activity of various growth factors in skin fibroblasts from n-ALD and X-ALD patients. Methods Skin fibroblast cultures from n-ALD and X-ALD patients, and controls were treated with 50 ng/mL of platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF) or insulin-like growth factor-1 (IGF-1) to examine DNA synthesis by 5-bromo-2′-deoxyuridine (BrdU) incorporation. Expression of receptors for PDGF, bFGF and IGF-1 was measured by western blotting. Serum levels of IGF-1 were assayed by enzyme-linked immunosorbent assay (ELISA). Results Fibroblasts from n-ALD and X-ALD patients had significantly (p < 0.01) less BrdU incorporation in response to fetal bovine serum (FBS). The mitogenic effect of PDGF, bFGF and IGF-1 was significantly lower in n-ALD as compared to control and X-ALD cells. X-ALD cells showed significant impairment in IGF-1-induced DNA synthesis. Expression of the FGF receptor (FGF-R) was significantly reduced in n-ALD cells. PDGF receptor remained unaffected, and IGF-1 receptor (IGF-1R) expression and serum IGF-1 levels were significantly (p < 0.01) reduced in n-ALD and X-ALD patients as compared to controls. Conclusions Growth factor activity differs in n-ALD and X-ALD patients, with marked impairment of IGF-1 function through receptor down-regulation.

Low Serum Levels of Fibroblast Growth Factor 2 in Gunn Rats: A Hyperbilirubinemia Animal Model of Schizophrenic Symptoms

2020 ◽  
Vol 19 (7) ◽  
pp. 503-508
Author(s):  
Maiko Hayashida ◽  
Sadayuki Hashioka ◽  
Kenji Hayashida ◽  
Shoko Miura ◽  
Keiko Tsuchie ◽  
...  
Keyword(s):  
Animal Model ◽  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Wistar Rats ◽  
Serum Levels ◽  
Significant Negative Correlation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Normal Strain ◽  
Fibroblast Growth ◽  
Gunn Rats

Background: Fibroblast growth factor (FGF) 2 (also referred to as basic FGF) is a multifunctional growth factor that plays a pivotal role in the pro-survival, pro-migration and pro-differentiation of neurons. Method: Because alterations in FGF2 levels are suggested to contribute to the pathogenesis schizophrenia, we investigated serum levels of FGF2 in the Gunn rat, a hyperbilirubinemia animal model of schizophrenic symptoms. Results: The enzyme-linked immunosorbent assay showed that the serum levels of FGF2 in Gunn rats were 5.09 ± 0.236 pg/mL, while those in the normal strain Wistar rats were 11.90 ± 2.142 pg/mL. The serum FGF2 levels in Gunn rats were significantly lower than those in Wistar rats. We also measured serum levels of unconjugated bilirubin (UCB) and found a significant negative correlation between UCB and FGF2 at serum levels in all the rats studied. Conclusion: Since it is known that FGF2 regulates dopaminergic neurons and have anti-neuroinflammatory effects, our finding suggests that low FGF2 levels may contribute to the pathogenesis of schizophrenia, in which disbalanced dopamin-ergic signaling and neuroinflammation are supposed to play certain roles.

Effect of steroids on cartilage metabolism "in vitro"

1986 ◽  
Vol 113 (4_Suppl) ◽  
pp. S35-S40 ◽  
Author(s):  
Marc V.L. DU CAJU ◽  
Raoul P. ROOMAN
Keyword(s):  
Growth Factor ◽  
Thymidine Incorporation ◽  
Normal Serum ◽  
Synthetic Analogue ◽  
Factor Activity ◽  
Poor Growth ◽  
Cartilage Metabolism ◽  
Glucocorticoid Administration

ABSTRACT Conditions characterized by high levels of glucocorticoids are associated with poor growth. Serum somatomedin or insulin-like growth factor activity measured by cartilage bioassay systems is low, but is generally not accompanied by a fall in somatomedin concentration. Hydrocortisone and a synthetic analogue, dexamethasone, impaired the serum stimulated "in vitro" 35S sulphate and 3H-thymidine incorporation in porcine rib cartilage at physiological concentrations. Hydrocortisone added at a concentration of 0,1 μg/ml decreased the potency of normal serum to 50 % of controls. Dexamethasone was at least 10 times more potent. Removal of "in vitro" or "in vivo" administered hydrocortisone with dextran-coated charcoal restored the sulphate and thymidine activity to normal. We conclude that physiological amounts of glucocorticoids inhibit the "in vitro" porcine cartilage metabolism. Glucocorticoid administration "in vivo" does not abolish the activity of the cartilage stimulating effect of serum but affects cartilage metabolism directly or by the induction of locally produced inhibitors of cartilage metabolism.

Platelet-Rich Plasma Powder: A New Preparation Method for the Standardization of Growth Factor Concentrations

2016 ◽  
Vol 45 (4) ◽  
pp. 954-960 ◽  
Author(s):  
Matthias Kieb ◽  
Frank Sander ◽  
Cornelia Prinz ◽  
Stefanie Adam ◽  
Anett Mau-Möller ◽  
...  
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Clinical Application ◽  
Whole Blood ◽  
Sports Medicine ◽  
Transforming Growth Factor ◽  
Platelet Rich Plasma ◽  
Transforming Growth Factor Β1 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tgf Β1

Background: Platelet-rich plasma (PRP) is widely used in sports medicine. Available PRP preparations differ in white blood cell, platelet, and growth factor concentrations, making standardized research and clinical application challenging. Purpose: To characterize a newly standardized procedure for pooled PRP that provides defined growth factor concentrations. Study Design: Controlled laboratory study. Methods: A standardized growth factor preparation (lyophilized PRP powder) was prepared using 12 pooled platelet concentrates (PCs) derived from different donors via apheresis. Blood samples and commercially available PRP (SmartPrep-2) served as controls (n = 5). Baseline blood counts were analyzed. Additionally, single PCs (n = 5) were produced by standard platelet apheresis. The concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), platelet-derived growth factor AB (PDGF-AB), transforming growth factor β1 (TGF-β1), insulin-like growth factor 1 (IGF-1), interleukin (IL)–1α, IL-1β, and IL-1 receptor agonist (IL-1RA) were analyzed by enzyme-linked immunosorbent assay, and statistical analyses were performed using descriptive statistics, mean differences, 95% CIs, and P values (analysis of variance). Results: All growth factor preparation methods showed elevated concentrations of the growth factors VEGF, bFGF, PDGF-AB, and TGF-β1 compared with those of whole blood. Large interindividual differences were found in VEGF and bFGF concentrations. Respective values (mean ± SD in pg/mL) for whole blood, SmartPrep-2, PC, and PRP powder were as follows: VEGF (574 ± 147, 528 ± 233, 1087 ± 535, and 1722), bFGF (198 ± 164, 410 ± 259, 151 ± 99, and 542), PDGF-AB (2394 ± 451, 17,846 ± 3087, 18,461 ± 4455, and 23,023), and TGF-β1 (14,356 ± 4527, 77,533 ± 13,918, 68,582 ± 7388, and 87,495). IGF-1 was found in SmartPrep-2 (1539 ± 348 pg/mL). For PC (2266 ± 485 pg/mL), IGF-1 was measured at the same levels of whole blood (2317 ± 711 pg/mL) but was not detectable in PRP powder. IL-1α was detectable in whole blood (111 ± 35 pg/mL) and SmartPrep-2 (119 ± 44 pg/mL). Conclusion: Problems with PRP such as absent standardization, lack of consistency among studies, and black box dosage could be solved by using characterized PRP powder made by pooling and lyophilizing multiple PCs. The new PRP powder opens up new possibilities for PRP research as well as for the treatment of patients. Clinical Relevance: The preparation of pooled PRP by means of lyophilization may allow physicians to apply a defined amount of growth factors by using a defined amount of PRP powder. Moreover, PRP powder as a dry substance with no need for centrifugation could become ubiquitously available, thus saving time and staff resources in clinical practice. However, before transferring the results of this basic science study to clinical application, regulatory issues have to be cleared.

Post-transcriptional control of the onset of DNA synthesis by an insulin-like growth factor

1984 ◽  
Vol 4 (9) ◽  
pp. 1807-1814
Author(s):  
J Campisi ◽  
A B Pardee
Keyword(s):  
Cell Cycle ◽  
Growth Factors ◽  
Growth Factor ◽  
Dna Synthesis ◽  
Transcriptional Control ◽  
S Phase ◽  
G1 Phase ◽  
Insulin Like Growth Factor ◽  
Igf I ◽  
Translational Inhibition

The control of eucaryotic cell proliferation is governed largely by a series of regulatory events which occur in the G1 phase of the cell cycle. When stimulated to proliferate, quiescent (G0) 3T3 fibroblasts require transcription, rapid translation, and three growth factors for the growth state transition. We examined exponentially growing 3T3 cells to relate the requirements for G1 transit to those necessary for the transition from the G0 to the S phase. Cycling cells in the G1 phase required transcription, rapid translation, and a single growth factor (insulin-like growth factor [IGF] I) to initiate DNA synthesis. IGF I acted post-transcriptionally at a late G1 step. All cells in the G1 phase entered the S phase on schedule if either insulin (hyperphysiological concentration) or IGF I (subnanomolar concentration) was provided as the sole growth factor. In medium lacking all growth factors, only cells within 2 to 3 h of the S phase were able to initiate DNA synthesis. Similarly, cells within 2 to 3 h of the S phase were less dependent on transcription and translation for entry into the S phase. Cells responded very differently to inhibited translation than to growth factor deprivation. Cells in the early and mid-G1 phases did not progress toward the S phase during transcriptional or translational inhibition, and during translational inhibition they actually regressed from the S phase. In the absence of growth factors, however, these cells continued progressing toward the S phase, but still required IGF at a terminal step before initiating DNA synthesis. We conclude that a suboptimal condition causes cells to either progress or regress in the cell cycle rather than freezing them at their initial position. By using synchronized cultures, we also show that in contrast to earlier events, this final, IGF-dependent step did not require new transcription. This result is in contrast to findings that other growth factors induce new transcription. We examined the requirements for G1 transit by using a chemically transformed 3T3 cell line (BPA31 cells) which has lost some but not all ability to regulate its growth. Early- and mid-G1-phase BPA31 cells required transcription and translation to initiate DNA synthesis, although they did not regress from the S phase during translational inhibition. However, these cells did not need IGF for entry into the S phase.

Late signals are required for the stimulation of DNA synthesis in rat mammary fibroblasts by growth factors

1996 ◽  
Vol 16 (3) ◽  
pp. 249-263 ◽  
Author(s):  
Hai-Lan Chen ◽  
Philip S. Rudland ◽  
John A. Smith ◽  
David G. Fernig
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Dna Synthesis ◽  
Maximal Response ◽  
High Concentration ◽  
Initial Concentration ◽  
Maximal Stimulation ◽  
Epidermal Growth ◽  
Lag Period ◽  
Stimulation Of

Maximal stimulation of DNA synthesis in quiescent rat mammary (Rama) 27 fibroblasts is elicited by epidermal growth factor (EGF) or basic fibroblast growth factor (bFGF) 18 h after the initial addition of the growth factors-the ‘lag’ period. At maximally-stimulating concentrations, EGF and bFGF are interchangeable 9 h after their initial addition. When the initial concentration of growth factor is below that required to elicit a maximal response, it is possible to increase the level of DNA synthesis by increasing the concentration of growth factor 9 h after its initial addition. When the initial concentration of growth factor is high, substitution by a lower concentration of growth factor after 9 h allows a greater proportion of cells to synthesize DNA than would be expected from a continuous low dose of growth factor. Similar results are obtained when both the growth factor and its concentration are changed 9 h after the initial addition of growth factor. However, when EGF at a low concentration is substituted for a high concentration of EGF or bFGF the resulting increase in the levels of DNA synthesis is greater when EGF rather than bFGF is added for a second time. The half-life of the growth-stimulatory signals delivered by EGF and by bFGF 9 h after their initial addition is 1–2 h. These results suggest that to stimulate DNA synthesis: (i) EGF or bFGF must deliver a signal(s) continuously; (ii) the initial signals produced by EGF and bFGF are equivalent; (iii) the signals produced between 9–18 h by EGF may be different to those produced by bFGF.

scholarly journals Insulin Growth Factor-I and Epidermal Growth Factor Receptors Recruit Distinct Upstream Signaling Molecules to Enhance AKT Activation in Mammary Epithelial Cells

Endocrinology ◽  
2006 ◽  
Vol 147 (12) ◽  
pp. 6027-6035 ◽  
Author(s):  
Jodie M. Fleming ◽  
Gwenaëlle Desury ◽  
Tiffany A. Polanco ◽  
Wendie S. Cohick
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Dna Synthesis ◽  
Egf Receptor ◽  
Mammary Epithelial ◽  
Insulin Receptor Substrate ◽  
Phosphatidylinositol 3 Kinase ◽  
Mapk Activation ◽  
Igf I ◽  
Epidermal Growth

IGF-I and epidermal growth factor (EGF) stimulate both normal mammary epithelial cell (MEC) growth and tumorigenesis. Whereas both growth factors increase DNA synthesis in MECs, how they evoke a greater response in combination when they activate similar signaling pathways remains unknown. In the present study, we investigated the signaling pathways by which these mitogens act in concert to increase DNA synthesis. Only EGF activated the MAPK pathway, and no further increase in MAPK activation was observed when both mitogens were added together. Both growth factors activated the phosphatidylinositol-3 kinase pathway, and simultaneous treatment enhanced phosphorylation of both AKT and its downstream target, p70S6K. The enhanced activation of AKT was observed at multiple time points (5 and 15 min) and growth factor concentrations (2.5–100 ng/ml). IGF-I activated AKT via insulin receptor substrate-1 and p85, the regulatory subunit of phosphatidylinositol-3 kinase. Treatment with EGF had no effect on insulin receptor substrate-1; however, it activated the EGF receptor, SHC, and c-Src. EGF treatment caused the association of SHC with Grb2 and Gab2 with phospho-SHC, phospho-Gab1, Grb2, and p85. Interestingly, inhibition of Src activation blocked the ability of EGF, but not IGF-I, to activate AKT. This corresponded with a decrease in phosphorylation of the EGF receptor and its association with phospho-SHC as well as downstream signaling. Unexpectedly, inhibition of Src increased basal MAPK activation. This is the first study to show that EGF and IGF-I use separate upstream components within a given MEC line to enhance AKT phosphorylation, contributing to increased DNA synthesis.

scholarly journals Sustained increase in 1,2-diacylglycerol precedes DNA synthesis in epidermal-growth-factor-stimulated fibroblasts. Evidence for stimulated phosphatidylcholine hydrolysis

1990 ◽  
Vol 267 (2) ◽  
pp. 501-507 ◽  
Author(s):  
T M Wright ◽  
H S Shin ◽  
D M Raben
Keyword(s):  
Growth Factors ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Dna Synthesis ◽  
De Novo ◽  
Phospholipid Metabolism ◽  
Intracellular Signals ◽  
Mitogenic Signalling ◽  
Epidermal Growth ◽  
Hydrolysis Of

A property common to many growth factors is that they must be present for several hours before the commitment to DNA synthesis and cell division occurs. The intracellular signals that are relevant during this period are poorly defined. We examined the formation of 1,2-diacylglycerol in IIC9 fibroblasts after stimulation with epidermal growth factor (EGF), and found that the mass of this lipid remained elevated for at least four hours. The concentration-dependence of EGF-stimulated 1,2-diacylglycerol production and [3H]thymidine incorporation were similar. Studies of phospholipid metabolism strongly suggested that phosphatidylcholine was the source of the 1,2-diacylglycerol generated in response to EGF. EGF did not stimulate the hydrolysis of other phospholipids, including the phosphoinositides, nor did it increase synthesis de novo of 1,2-diacylglycerol. This pattern of sustained 1,2-diacylglycerol formation from phosphatidylcholine may be important in the mitogenic signalling of EGF and potentially other growth factors.

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