Growth regulation最新文献

{"title":"KGF and EGF differentially regulate the phenotype of prostatic epithelial cells.","authors":"D M Peehl,&nbsp;S T Wong,&nbsp;J S Rubin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Previous studies indicate that keratinocyte growth factor (KGF) acts as a paracrine factor in the prostatic epithelium and epidermal growth factor (EGF) acts as an autocrine factor. In serum-free medium, KGF or EGF promoted similar growth of human prostatic epithelial cells. Response to two growth-inhibitory factors (suramin and transforming growth factor-beta), and expression of keratins and prostate-specific antigen (PSA), were similar with either mitogen. However, colonies in medium with KGF were very compact with extensive intercellular bonds, whereas colonies with EGF consisted of widely-separated cells. Growth was decreased to a greater extent by deletion of growth factors from medium with KGF versus EGF, and retinoic acid was 10-fold more potent at inducing growth inhibition and differentiation-associated keratin with KGF compared with EGF. We conclude that regulation of growth and differentiation in the prostate might vary depending on the availability of KGF versus EGF.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"6 1","pages":"22-31"},"PeriodicalIF":0.0,"publicationDate":"1996-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19691912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid clearance of human insulin-like growth factor binding protein-3 from the rat circulation and cellular localization in liver, kidney and stomach.","authors":"E Arany,&nbsp;P Zabel,&nbsp;D J Hill","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The gastrointestinal tract represents a major site for the trophic actions of insulin-like growth factors (IGFs), which may be derived in vivo from a large circulating pool. The high capacity binding protein for IGFs in blood is IGF binding protein-3 (IGFBP-3), which is largely complexed with an acid-labile subunit (ALS). However, we and others have shown that IGFBP-3 not complexed with ALS can rapidly leave the circulation, and may carry IGFs to peripheral tissues. In this study we investigated the transfer of recombinant, glycosylated human (h)IGFBP-3 from the rat circulation to the stomach and intestine, compared with liver and kidney. [125I]-labeled IGFBP-3 was administered into the tail vein of conscious male rats, which were killed between 5 min and 2 h later. Blood was taken for the preparation of plasma, and the liver, kidneys, stomach and intestine were removed either for estimation of the associated radioactivity, or fixed for autoradiographic analysis of histological sections. Following injection, [125I]-labeled IGFBP-3 was associated, in part, with a 150 kDa complex in plasma within 10 min when analyzed by gel filtration chromatography. However, 84% of the administered IGFBP-3 had already left the circulation, and 40% of the initial injected dose was accumulated in liver by 5 min, with a further 4% localized in the kidneys. Autoradiographic analysis showed that IGFBP-3 was selectively accumulated within Kupffer cells of the liver, and by the glomeruli and proximal tubules of the kidney. Little radiolabeled IGFBP-3 was recovered from the small intestine, but 14% of the initial injected dose was found within the stomach after 2 h, and a further 12% within the stomach contents. Autoradiographic localization within the stomach showed that the [125I]-labeled IGFBP-3 was primarily associated with the mucosal lining and gastric glands. Separation on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed that the majority of the radioactivity associated with the stomach contents represented small, degraded peptides. These results suggest that while a rapid clearance of IGFBP-3 is achieved by the liver and kidney, a longer term accumulation occurs in the stomach with a luminal secretion. This may represent a delivery system by which circulating IGFs may reach gastric tissue.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"6 1","pages":"32-41"},"PeriodicalIF":0.0,"publicationDate":"1996-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19691913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Iodide-dependent regulation of thyroid follicular cell proliferation: a mediating role of autocrine insulin-like growth factor-I.","authors":"H M Beere,&nbsp;A J Cowin,&nbsp;J Soden,&nbsp;S P Bidey","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>An inhibitory action of intracellular iodide on the autocrine production of insulin-like growth factor-I (IGF-I) by thyroid follicular cells (TFCs) in vitro has been investigated as a possible mechanism underlying the iodide-dependent control of TFC proliferation. IGF-I release from primary monolayer cultures of porcine TFCs increased 5-fold between 24 and 168 h of incubation. Confirmation of a mediating role of IGF-I in TFC proliferation was obtained by exposing TFCs to an immunoadsorbing IGF-I antiserum, which led to a significant (P < 0.05) decline in [methyl-3H]thymidine incorporation, relative to TFCs exposed to preimmune serum. Exposure of TFCs to sodium iodide (NaI; 0.1-100 mumol/l) led to an attenuation of the IGF-I content of the cell-conditioned medium. This was accompanied by a reduction in [methyl-3H]thymidine incorporation that was affected by IGF-I immunoneutralization. The inhibitory effect of NaI on IGF-I production and [methyl-3H]thymidine incorporation were reversed by the thionamide compound methimazole (MMI; 1 mmol/l), exposure to which also led to significant (P < 0.001) increases above control values. However, a residual suppressive effect of NaI on [methyl-3H]thymidine incorporation suggested that certain of the TFC growth-attenuating effects of iodide may not be dependent upon organification. While providing evidence, therefore, for a direct relationship between iodide exposure, suppression of autocrine IGF-I production and a regulation of TFC proliferation, the present studies also suggest that suppression of TFC proliferation by iodide may be partially mediated by MMI-insensitive events.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"203-9"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunohistochemical localization of insulin-like growth factor-II in the perinatal rat gonad.","authors":"S Koike,&nbsp;T Noumura","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>To clarify the participation of insulin-like growth factor type-II (IGF-II) in rat gonadal differentiation, immunohistochemical localization of IGF-II was chronologically studied in Sprague-Dawley rat gonads from gestational day (GD) 13 to postnatal day (PD) 21 by using avidin-biotin complex technique. In male gonads, most cells were negative to IGF-II immunostaining during the perinatal period. Only Leydig/interstitial cells expressed positive reactivity from GD 21 to PD 11: the intensity of staining and the number of positive cells were gradually increased until PD 11. In female gonads, almost all cells showed negative immunoreactivity. Mesonephric tubules in both sexes exhibited slight or moderate reactivity on GD 13. These results indicate that IGF-II is likely to participate in the regression of fetal-type Leydig cells and/or the proliferation of adult-type Leydig cells around birth, and in the development of mesonephric tubules in the initial stage of gonadal differentiation.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"185-89"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expression of aberrantly spliced growth hormone receptor mRNA in the sex-linked dwarf chicken, Gifu 20.","authors":"M Tanaka,&nbsp;Y Hayashida,&nbsp;M Wakita,&nbsp;S Hoshino,&nbsp;K Nakashima","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The structure and expression of the growth hormone receptor (GHR) gene have been studied in a sex-linked dwarf (SLD) chicken strain, Gifu 20. No gross structural change in the receptor gene was observed by Southern blot analysis, however, a transcript of 5.5 killobases (kb), which was approximately 1 kb larger than the usual chicken full length-GHR mRNA was detected in the dwarf chicken by Northern blot analysis. GHR cDNA was obtained from dwarf chicken liver RNA by reverse transcription-polymerase chain reaction, and nucleotide sequence analysis revealed that it contained an intron sequence of the GHR gene. The unspliced intron showed a single point mutation at the donor site from GT to GC, and an aberrant stop codon was generated in the extracellular domain-coding region. Thus, the mutation resulting in an inappropriate splicing of the GHR gene transcript is considered to be the cause of this dwarf chicken.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"218-23"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Skeletal growth of transgenic mice with elevated levels of circulating insulin-like growth factor-II.","authors":"E Wolf,&nbsp;K Rapp,&nbsp;W F Blum,&nbsp;H Kolb,&nbsp;G Brem","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Insulin-like growth factor-II (IGF-II) is a major factor produced by skeletal tissues. To evaluate endocrine effects of IGF-II on bone growth, we measured skeletal dimensions of 12-week-old transgenic mice harbouring fusion genes where a human IGF-II cDNA is transcriptionally controlled by rat phospheonolpyruvate carboxykinase (PEPCK) promoter sequences. Transgene expression in liver, kidney and intestine resulted in circulating IGF-II levels in transgenic mice which were 2-3-fold higher than in controls. Serum IGF-I concentrations of transgenic mice were lower than in controls. Body weight was not influenced by the expression of the IGF-II transgene. Only 1 out of 5 measurements taken from the radius was significantly affected by the presence of the transgene, while in 60 measurements taken from eight other bones there was no difference between transgenic mice and controls. Furthermore, serum levels of calcium and phosphate as well as alkaline phosphatase activity were not significantly altered in PEPCK-IGF-II transgenic mice. Our findings demonstrate that moderately increased levels of circulating IGF-II do not cause major changes in skeletal growth and turnover in mice. This may be due to a lack of activity of circulating IGF-II on bone growth or to physiological consequences of elevated IGF-II, like a reduction of circulating IGF-I or an increase in IGF binding proteins.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"177-83"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-competitive time-resolved immunofluorometric assays for determination of human insulin-like growth factor I and II.","authors":"J Frystyk,&nbsp;B Dinesen,&nbsp;H Orskov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We present sensitive non-competitive time-resolved immunofluorometric assays (TR-IFMAs) for IGF-I and IGF-II based on monoclonal antibodies. Assays were performed in microtest-plate wells: the first antibodies were immobilized on the solid matrix, the second labelled with the chelate derivative of Europium (Eu3+). The obtained specificities and sensitivities were high: IGF-I and IGF-II cross-reactivity in heterologous assay was below 0.0002%. The detection limits were 0.0025 micrograms/l and 0.010 micrograms/l for the IGF-I and IGF-II assay, respectively. The operating range included upwards: 2.5 micrograms/l (IGF-I) and 10.0 micrograms/l (IGF-II). This implies that all clinically relevant serum concentrations could be measured in one final dilution (1:1066 for IGF-I and 1:2132 for IGF-II) after acid ethanol extraction. The high sample dilution with buffer made further neutralization or evaporation of serum acid ethanol extracts unnecessary. Interassay variation of the assays was below 10%.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"169-76"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19718240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the insulin-like growth factor (IGF) axis in the serum of maternal and fetal macaques (Macaca mulatta and Macaca fascicularis).","authors":"A F Tarantal,&nbsp;S E Gargosky","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The insulin-like growth factors (IGFs) are key effectors of fetal growth and development which are modulated by serum carrier proteins (IGF binding proteins [IGFBPs]). Studies were performed to evaluate the developmental profile of IGFs and IGFBPs in the macaque, an important nonhuman primate model for human development and disease. IGF-I, IGF-II, and IGFBP-3 were studied in the rhesus (Macaca mulatta) and long-tailed (Macaca fascicularis) monkey fetus and dam during the second and third trimesters of pregnancy. Serial fetal blood samples were collected by cardiocentesis every 10 days from gestational day (GD) 90-160, and at 1 month postnatal age; maternal blood samples were collected at similar timepoints. Results indicated that maternal sera IGF-I and IGF-II did not change significantly whereas fetal concentrations of serum IGF-I and IGF-II increased approximately two-fold during the second to the third trimesters. No significant differences were detected between the two species. Western-ligand blot analysis revealed predominant IGFBPs of 45-40 (IGFBP-3) and 28 kDa (IGFBP-1) in both the maternal and fetal compartments, and Western-immunoblot analysis using a specific antisera against IGFBP-3 indicated 45-40 and 28 kDa immunoreactive forms. Thus, although IGF-I, IGF-II, and IGFBP-3 remained relatively unaffected in maternal sera during this period of gestation, fetal concentrations of IGF-I, IGF-II, and IGFBP-3 increased in a developmental profile similar to the human fetus.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"190-8"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulation of hepatic mRNA levels for the growth hormone receptor in rats with altered thyroid status.","authors":"X Y Shen,&nbsp;J Rodriguez-Arnao,&nbsp;R J Ross","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Changes in thyroid status have a major effect on the GH/IGF-I axis. In the rat, there is a single gene for the growth hormone receptor (GHR), that is transcribed into two different sized mRNA transcripts following alternative splicing, one transcript codes for the GHR (4.0-4.5 kb) and the other growth hormone binding protein (GHBP) (1.2-1.3 kb). We have studied the regulation of hepatic GHR gene expression by thyroid hormones in male Wistar rats rendered hypothyroid (n = 6) and hyperthyroid (n = 6) compared to controls (n = 6). By northern blot analysis, two transcripts with an estimated size of 4.2 and 1.2 kb, respectively, were detected in all groups. Hyperthyroidism was associated with a significant increase in the 4.2 kb transcript compared to hypothyroidism (P < 0.05), but no changes were observed in the 1.2 kb transcript. Thus, our results suggest that in the rat hyperthyroidism is associated with either increased hepatic gene transcription or decreased clearance of the 4.2 kb transcript for the GHR compared with hypothyroidism.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"199-202"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of IGF-I, alone and in combination with 17 beta-oestradiol, on bone remodelling parameters in ovariectomised rats.","authors":"J Verhaeghe,&nbsp;E Van Herck,&nbsp;R van Bree,&nbsp;R Bouillon","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>We studied the effects of recombinant human IGF-I (250 micrograms/day) and/or 17 beta-oestradiol (E2; 5 or 50 micrograms/kg/day), s.c., for 28 days, on plasma IGF-I and 1,25-(OH)2 vitamin D3 concentrations and on biochemical indices of bone remodelling (plasma osteocalcin, urinary pyridinolines) in 3 month-old rats that had been ovariectomised (OVX) 6 weeks before. Ten weeks after ovariectomy, plasma 1,25-(OH)2D3 was increased, but IGF-I and bone remodelling indices were within the normal range. RhIGF-I administration to OVX rats increased both IGF-I and 1,25-(OH)2D3 concentrations, as well as plasma osteocalcin and urinary pyridinoline excretion. By contrast, E2 decreased plasma IGF-I and 1,25-(OH)2D3 and the markers of bone remodelling. The combination of rhIGF-I and E2 resulted in intermediate effects. Multiple regression analysis showed that IGF-I correlated with plasma osteocalcin, and also with the urinary excretion of pyridinolines. The data shows that rhIGF-I stimulates bone remodelling in growing OVX rats, and that circulating IGF-I is a determinant of bone remodelling in vivo.</p>","PeriodicalId":77148,"journal":{"name":"Growth regulation","volume":"5 4","pages":"210-7"},"PeriodicalIF":0.0,"publicationDate":"1995-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19717489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}