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Andoh T. Plasma insulin levels are regulated by release, rather than transcription or translation, in barfin flounder, Verasper moseri. Comp Biochem Physiol A Mol Integr Physiol 2015; 184:27-33. [PMID: 25660295 DOI: 10.1016/j.cbpa.2015.01.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 01/21/2015] [Accepted: 01/26/2015] [Indexed: 11/19/2022]
Abstract
We evaluated whether transcription or translation of the preproinsulin gene or insulin release into plasma is the primary regulator of plasma insulin level in barfin flounder. Three experimental groups were used: one tested 2h after feeding (Fed), one tested after fasting for 5 days (Fasted), and one tested 2 h after feeding following 5 days of fasting (Refed). No significant differences in insulin transcription, insulin concentrations in the principal islets (PI), or plasma total insulin-like growth factor-I (IGF-I) levels were observed between the three groups. In contrast, plasma insulin level in the Fasted group was significantly lower (P<0.002) than that in the other groups. These results suggest that insulin release is the primary regulator of plasma insulin level and is more sensitive to short-term changes in nutritional conditions than IGF-I level. Furthermore, we estimated the capacity for insulin release. Based on various individual measures, the average insulin stored in the PI was 82.8 μg/kg body weight (BW), and the maximum plasma content of insulin was estimated to be <1.7 μg/kg BW. The half-life of plasma insulin in diabetogenic chemically (alloxan) treated flounder injected with insulin was estimated to be 2.79 h, which is much longer than that in mammals, assuming a two-compartment model for the β phase. These results suggest that the capacity for insulin release in fish is ensured by at least two systems, such as the ability to store excess insulin in Brockman bodies, and enhanced efficiency of insulin storage by elongating its half-life.
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Affiliation(s)
- Tadashi Andoh
- Seikai National Fisheries Research Institute, Fisheries Research Agency, Taira-machi 1551-8, Nagasaki 851-2213, Japan.
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Yan Y, Cui H, Guo C, Li J, Huang X, Wei J, Qin Q. An insulin-like growth factor homologue of Singapore grouper iridovirus modulates cell proliferation, apoptosis and enhances viral replication. J Gen Virol 2013; 94:2759-2770. [PMID: 24062533 DOI: 10.1099/vir.0.056135-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Insulin-like growth factors (IGFs) play crucial roles in regulating cell differentiation, proliferation and apoptosis. In this study, a novel IGF homologue gene (IGF-like) encoded by Singapore grouper iridovirus (SGIV) ORF062R (termed SGIV–IGF), was cloned and characterized. The coding region of SGIV–IGF is 771 bp in length, with a variable number of tandem repeats (VNTR) locus at the 3′-end. We cloned one isoform of this novel gene, 582 bp in length, containing the predicted IGF domain and 3.6 copy numbers of the 27 bp repeat unit. SGIV–IGF was an early transcribed gene during viral infection, and SGIV–IGF was distributed predominantly in the cytoplasm with a diffused granular appearance. Intriguingly, overexpression of SGIV–IGF was able to promote the growth of grouper embryonic cells (GP cells) by promoting G1/S phase transition, which was at least partially dependent on its 3′-end VNTR locus. Furthermore, viral titre assay and real-time quantitative PCR (RT-qPCR) analysis proved that SGIV–IGF could promote SGIV replication in grouper cells. In addition, overexpression of SGIV–IGF mildly facilitated apoptosis in SGIV-infected non-host fathead minnow (FHM) cells. Together, our study demonstrated a novel functional gene of SGIV which may regulate viral replication and cellular processes through multiple mechanisms that appear to be cell type-dependent.
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Affiliation(s)
- Yang Yan
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
| | - Huachun Cui
- Department of Medicine, University of Alabama at Birmingham, 901 19th Street South, Birmingham, AL 35294, USA
| | - Chuanyu Guo
- University of Chinese Academy of Sciences, Beijing, PR China
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
| | - Jun Li
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou 510080, PR China
| | - Xiaohong Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
| | - Jingguang Wei
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
| | - Qiwei Qin
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, PR China
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Salmerón C, Acerete L, Gutiérrez J, Navarro I, Capilla E. Characterization and endocrine regulation of proliferation and differentiation of primary cultured preadipocytes from gilthead sea bream (Sparus aurata). Domest Anim Endocrinol 2013; 45:1-10. [PMID: 23535263 DOI: 10.1016/j.domaniend.2013.02.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 02/19/2013] [Accepted: 02/20/2013] [Indexed: 12/25/2022]
Abstract
A preadipocyte primary cell culture was established to gain knowledge about adipose tissue development in gilthead sea bream (Sparus aurata), one of the most extensively produced marine aquaculture species in the Mediterranean. The preadipocytes obtained from the stromal-vascular cell fraction of adipose tissue proliferated in culture, reaching confluence around day 8. At that time, the addition of an adipogenic medium promoted differentiation of the cells into mature adipocytes, which showed an enlarged cytoplasm filled with lipid droplets. First, cell proliferation and differentiation were analyzed under control and adipogenic conditions during culture development. Next, the effects of insulin, GH, and IGF-I on cell proliferation were evaluated at day 8. All peptides significantly stimulated proliferation of the cells after 48 h of incubation (P < 0.002 for GH and IGF-I and P < 0.05 for insulin), despite no differences were observed between the different doses tested. Subsequently, the effects of insulin and IGF-I maintaining differentiation when added to growth medium were studied at day 11, after 3 d of induction with adipogenic medium. The results showed that IGF-I is more potent than insulin enhancing differentiation (P < 0.01 for IGF-I compared with the control). In summary, a primary culture of gilthead sea bream preadipocytes has been characterized and the effects of several regulators of growth and development have been evaluated. This cellular system can be a good model to study the process of adipogenesis in fish, which may help improve the quality of the product in aquaculture.
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Affiliation(s)
- C Salmerón
- Department of Physiology and Immunology, Faculty of Biology, University of Barcelona, Av. Diagonal 643, Barcelona 08028, Spain
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Capilla E, Teles-García A, Acerete L, Navarro I, Gutiérrez J. Insulin and IGF-I effects on the proliferation of an osteoblast primary culture from sea bream (Sparus aurata). Gen Comp Endocrinol 2011; 172:107-14. [PMID: 21447336 DOI: 10.1016/j.ygcen.2011.03.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Revised: 03/03/2011] [Accepted: 03/19/2011] [Indexed: 11/19/2022]
Abstract
Bone deformities in several fish species, like gilthead sea bream (Sparus aurata), are currently a major problem in aquaculture. To gain knowledge of fish skeletal development, a primary cell culture has been established from sea bream vertebra. The initial fibroblastic phenotype of the cells changed to a polygonal shape during the culture, and the addition of an osteogenic medium promoted the deposition of minerals in the extracellular matrix. Cell proliferation was analyzed using the MTT assay in control and mineralizing conditions at different culture days, up to day 20. The capacity of the cells to differentiate into osteoblasts was evaluated using Alizarin red stain. The cells showed slightly increased proliferation and differentiation in the presence of osteogenic medium. Furthermore, pluripotentiality of these cells was demonstrated by inducing them to differentiate into adipocytes, and the accumulation of lipids into the cells was detected with Oil Red O staining. Subsequently, the effects of insulin (1, 10, 100 and 1000 nM) and IGF-I (0.1, 1 and 10nM) on cell proliferation were evaluated with the MTT assay at day 3. Both peptides significantly stimulated the proliferation of the cells in a dose-dependent manner after either 24 or 48 h of incubation, with IGF-I apparently being more potent than insulin. In summary, a primary culture of sea bream osteoblasts has been characterized. This cellular system can be a good model to study the process of osteoblastogenesis in fish and its endocrine regulation, which may help to improve the quality of the product in aquaculture.
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Affiliation(s)
- Encarnación Capilla
- Department of Physiology and Immunology, Faculty of Biology, University of Barcelona, Av. Diagonal 645, Barcelona 08028, Spain.
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Douxfils J, Mandiki S, Marotte G, Wang N, Silvestre F, Milla S, Henrotte E, Vandecan M, Rougeot C, Mélard C, Kestemont P. Does domestication process affect stress response in juvenile Eurasian perch Perca fluviatilis? Comp Biochem Physiol A Mol Integr Physiol 2011; 159:92-9. [DOI: 10.1016/j.cbpa.2011.01.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 01/27/2011] [Accepted: 01/30/2011] [Indexed: 10/18/2022]
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Gao L, Zan L, Wang H, Hao R, Zhong X. Polymorphism of somatostatin gene and its association with growth traits in Chinese cattle. Genet Mol Res 2011; 10:703-11. [DOI: 10.4238/vol10-2gmr1029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Hanson A, Poudyal D, Hagemeister A, Reindl KM, Sheridan MA. The ERK and PI3K signaling pathways mediate inhibition of insulin-like growth factor-1 receptor mRNA expression by somatostatin. Mol Cell Endocrinol 2010; 315:57-62. [PMID: 19815052 DOI: 10.1016/j.mce.2009.09.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 09/28/2009] [Accepted: 09/30/2009] [Indexed: 01/11/2023]
Abstract
Somatostatins (SSs) are a structurally diverse family of peptide hormones that regulate various aspects of growth, development, and metabolism in vertebrates. Previously, we showed that SSs inhibit mRNA and functional expression of insulin-like growth factor-1 receptors (IGFR1) in gill filaments of rainbow trout. In this study, we used trout gill filaments, which express in high abundance two distinct IGFR1s, IGFR1A and IGFR1B, to examine the mechanism(s) through which SSs exert their inhibitory effects on IGFR1 expression. SS-14, a predominat SS isoform, directly stimulated the phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (Akt), a downstream target of phosphatidylinositol 3-kinase (PI3K), in filaments incubated in vitro. Activation of ERK and Akt by SS-14 was rapid, occuring within 5-10 min, and was concentration-dependent. The ERK pathway inhibitor, U0126, retarded SS-14-stimulated phosphorylation of ERK 1/2, whereas the PI3K inhibitor, LY294002, blocked SS-14-stimulated phosphorylation of Akt. SS-14-inhibited expression of IGFR1 mRNAs was blocked by both U0126 and LY294002. These data indicate that SS-14 inhibition of IGFR1 mRNA expression is mediated through the ERK and PI3K/Akt signaling pathways.
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Affiliation(s)
- Andrea Hanson
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58108-6050, USA
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Takei Y, Loretz CA. The gastrointestinal tract as an endocrine/neuroendocrine/paracrine organ: organization, chemical messengers and physiological targets. Fish Physiology 2010. [DOI: 10.1016/s1546-5098(10)03007-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Polakof S, Soengas JL. Differential effects of in vivo and in vitro lactate treatments on liver carbohydrate metabolism of rainbow trout. Comp Biochem Physiol A Mol Integr Physiol 2008; 151:205-10. [DOI: 10.1016/j.cbpa.2008.06.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 06/23/2008] [Accepted: 06/24/2008] [Indexed: 10/21/2022]
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Abstract
Metabolism of vertebrates integrates a vast array of systems and processes, including the pursuit and capture of food, feeding and digestion of ingested food, absorption and transport of nutrients, assimilation, partitioning and utilization of energy, and the processing and elimination of wastes. Fish, which are the most diverse group of vertebrates and occupy a wide range of habitats and display numerous life history patterns, have proven to be important models for the study of the structure, biosynthesis, evolution, and function of gastroenteropancreatic (GEP) hormones. Food intake is promoted by galanin, neuropeptide Y, and pancreatic polypeptide (PP), while cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1) inhibit food intake. Digestion of ingested food is facilitated by CCK, PP, and secretin by coordinating gastrointestinal tract motility and regulation of exocrine secretion. Somatostatins (SS), on the other hand, generally inhibit exocrine secretions. Insulin facilitates assimilation by promoting the uptake of nutrient molecules (e.g., glucose, amino acids, and fatty acids) into cells. Insulin also is generally anabolic and stimulates the synthesis and deposition of energy reserves (e.g., glycogen, triacylglycerol) as well as of proteins, thereby facilitating organismal growth. Insulin-like growth factors (e.g., IGF-1) also promote cell proliferation and organismal growth. Breakdown and mobilization of stored energy reserves is stimulated by glucagon, GLP-1, and SS. Somatostatins also affect metabolism and reproduction via their effects on the thyroid axis as well as growth via effects on growth hormone (GH) release and perhaps directly via modulation of GH sensitivity. Studies in fish have revealed that GEP hormones play an important role in coordinating the various aspects of metabolism with each other and with the physiological and developmental status of the animal as well as with the environment.
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Affiliation(s)
- Laura E Nelson
- Department of Biological Sciences, North Dakota State University, Fargo, ND 58105, USA
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Alexander ELR, Dooley KC, Pohajdak B, Xu BY, Wright JR. Things we have learned from tilapia islet xenotransplantation. Gen Comp Endocrinol 2006; 148:125-31. [PMID: 16413551 DOI: 10.1016/j.ygcen.2005.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Revised: 11/29/2005] [Accepted: 12/01/2005] [Indexed: 11/18/2022]
Abstract
An islet xenotransplantation model has been developed using tilapia (Oreochromis niloticus) as the donors. Studies using this model for the treatment of experimental type 1 diabetes in mice have produced promising results including the maintenance of long-term normoglycemia and mammalian-like glucose tolerance profiles in islet graft recipients. Islet encapsulation has also provided a promising method for the prevention of graft rejection, and strains of transgenic tilapia expressing a [desThrB30] human insulin molecule have been produced. In addition to studying islet transplantation for the treatment of type 1 diabetes, these studies have also produced insights into piscine glucose homeostasis. Studies demonstrating the glucose responsiveness of tilapia islets are described. In addition, work performed by our group and by others pertaining to presence and nature of piscine glucose transporters is reviewed. Finally, studies addressing some of the broader challenges of islet xenotransplantation are discussed with particular attention paid to the post-transplantation fate of the various islet cell populations and the proteins they produce.
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Affiliation(s)
- Emily L R Alexander
- Department of Pathology and Laboratory Medicine, IWK Health Centre and Dalhousie University, Halifax, NS, Canada
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Gricourt L, Bonnec G, Boujard D, Mathieu M, Kellner K. Insulin-like system and growth regulation in the Pacific oyster Crassostrea gigas: hrIGF-1 effect on protein synthesis of mantle edge cells and expression of an homologous insulin receptor-related receptor. Gen Comp Endocrinol 2003; 134:44-56. [PMID: 13129502 DOI: 10.1016/s0016-6480(03)00217-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The involvement of molecules belonging to the insulin/IGF family in regulation of growth has been investigated in the Pacific oyster Crassostrea gigas. In vitro biological effects of human recombinant IGF-1 (hrIGF-1) on mantle edge cells, involved in oyster shell and soft body growth, were studied over an annual cycle. In mantle edge cells hrIGF-1 stimulates protein synthesis of 56+/-5.1% over basal for 10(-10) M in September with in addition a clear dose-effect corresponding to the highest shell growth period, and 57.5+/-3.45% over basal for 10(-11) M in March and 51+/-5.4% over basal for 10(-10) M in April corresponding to the period of mantle growth. These insulin-like effects were associated with the expression of a recently identified C. gigas insulin receptor-related receptor (CIR) in mantle edge cells as demonstrated by RT-PCR. Moreover, in situ hybridisation (ISH) confirmed this expression at the level of the inner and outer epithelia involved in mantle growth and shell formation.
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Affiliation(s)
- L Gricourt
- Laboratoire de Biologie et Biotechnologies Marines, EA 962, UMR IFREMER Physiologie et Ecophysiologie des Mollusques Marins, Université de Caen Basse-Normandie, Caen Cedex 14032, France
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Capilla E, Médale F, Navarro I, Panserat S, Vachot C, Kaushik S, Gutiérrez J. Muscle insulin binding and plasma levels in relation to liver glucokinase activity, glucose metabolism and dietary carbohydrates in rainbow trout. Regul Pept 2003; 110:123-32. [PMID: 12527145 DOI: 10.1016/s0167-0115(02)00212-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Rainbow trout were fed for 10 weeks with either a carbohydrate-free diet (C-free) or with four experimental diets containing various levels (20 or 40%) and sources of starch (extruded wheat or peas) in order to examine metabolic utilisation of dietary vegetable carbohydrates and its endocrine control. The study was focused on the parameters described as limiting in glucose metabolism in fish. Feeding trials were conducted at 8 and 18 degrees C to establish whether carbohydrate-rich diets can be used in trout farming irrespective of water temperature. At both temperatures, pea diets (especially the highest level) resulted in a feed efficiency as high as the C-free diet. Fish had similar growth rates except when fed the low wheat content diet. Glycaemia values 6 h after feeding were significantly higher in trout fed carbohydrate diets than those given the C-free diet, whereas plasma insulin levels were similar independently of the levels of dietary starch. This study provides the first evidence that glucokinase (GK) activity and mRNA level in trout liver increase in proportion to the content of dietary starch. Nevertheless, these changes were not correlated with plasma insulin levels. Insulin-like growth factor-I (IGF-I) binding and number of receptors in skeletal muscle were consistently higher than those for insulin but no diet-induced differences were found for any of these parameters. Temperature clearly affected the postprandial profile of glucose and insulin, which both showed lower levels 6 h after feeding at 8 degrees C than at 18 degrees C, which was consistent with a lower feed intake. Glucose and insulin levels decreased markedly 24 h after feeding at 18 degrees C, while they were still high at 8 degrees C, an observation concordant with delayed transit rate. These findings indicate satisfactory adaptation of rainbow trout to diets with a relatively high vegetable starch content, especially when provided as extruded peas, and indicate that diets with increased levels of carbohydrates can be used in this species even when it is reared at low temperature.
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Affiliation(s)
- Encarnación Capilla
- Départament de Fisiologia, Facultat de Biologia, D. III, Universitat de Barcelona, Avda. Diagonal 645, E-08028, Barcelona, Spain
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Méndez E, Smith A, Figueiredo-Garutti ML, Planas JV, Navarro I, Gutiérrez J. Receptors for insulin-like growth factor-I (IGF-I) predominate over insulin receptors in skeletal muscle throughout the life cycle of brown trout, Salmo trutta. Gen Comp Endocrinol 2001; 122:148-57. [PMID: 11316420 DOI: 10.1006/gcen.2001.7621] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Insulin and IGF-I binding has been studied in brown trout (Salmo trutta) wheat germ agglutinin semipurified receptors from embryos (organogenesis), larvae (yolk sac), juveniles (2.98 +/- 0.21 g bw) and adults (111.6 +/- 6.92 and 522 +/- 53 g bw). Embryos and larvae were sampled at 5 and 12 weeks after fertilization (December 1999 and February 2000) and juvenile and adults were taken simultaneously (July 1999) and under the same feeding conditions to minimize potential nutritional and seasonal effects. Insulin receptor number was maximal at 12 weeks (144 fmol/mg glycoprotein) and progressively decreased in subsequent samplings. No alterations in affinity were detected (K(d) range, 0.21-0.32 nM) and changes in number of receptor paralleled changes in total specific binding. IGF-I receptor number was highest at 5 weeks (1044 fmol/mg) and was significantly higher than values for insulin in all samplings. The affinity of IGF-I receptor did not change (K(d) range, 0.11-0.18 nM) but was consistently higher than that for the insulin receptor. A more rapid decrease of IGF-I binding and receptor number was found with age. However, the ratio of insulin/IGF-I binding established in 12-week-old larvae (0.18 +/- 0.01) was thereafter maintained at very similar values in juveniles and adults (0.15-0.17). Tyrosine kinase activity (TKA) for insulin receptors ranged between 136 and 183% and there were no significant changes with age. For the IGF-I receptor, TKA ranged from 174 to 281% and was significantly higher in 5-week-old larvae coincident with the highest levels of receptor number and declined gradually in parallel with binding levels. In conclusion, the greater abundance of IGF-I receptors during embryonic and larval development is maintained throughout juvenile and adult stages. This would suggest a key role for IGF-I in the growth and metabolism of trout muscle.
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Affiliation(s)
- E Méndez
- Departament de Fisiologia, Facultat de Biologia, D. III, Universitat de Barcelona, Avinguda Diagonal 645, Barcelona, 08028, Spain
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Abstract
Several preproinsulin cDNAs were isolated and characterized from four members of the Osteoglossomorpha (an ancient teleost group); Osteoglossum bicirrhosum (arawana), Pantodon buchholzi (butterfly fish), Notopterus chitala (feather fin knife fish), Hiodon alosoides (goldeye) and Gnathonemus petersii (elephantnose). In addition, we isolated and characterized the preproinsulin cDNA from Catostomus commersoni (white sucker, as a representative of a generalized teleost). The comparative analysis of the sequences revealed conservation of the cystine residues known to be involved in the formation of the disulfide bridges, as well as residues involved in the hexamer formation, except for B-17 in the butterfly fish, the arawana and the goldeye. However, the N-terminus of the B-chain was very weakly conserved among the species studied. Residues known to be significant for maintaining receptor-binding conformation and those known to comprise the receptor-binding domain were all conserved, except for a conservative substitution at B13, aspartate substituted glutamate in the arawana, goldeye, butterfly fish and white sucker, and at B16, phenylalanine substituted tyrosine in the elephantnose. Phylogenetic analysis of the sequences revealed a monophyletic grouping of the osteoglossomorphs, and showed that they were not the most basal living teleost. Comparative sequence analysis of preproinsulins among the osteoglossomorphs was useful in assessment of intergroup relationship, relating elephantnose with the feather fin knife fish and the arawana, butterfly fish, and goldeye. This arrangement of species is consistent with relationships based on other more classical parameters, except for the goldeye which was assessed as being sister to all the osteoglossomorphs. The white sucker was grouped with the common carp and both are cyprinids.
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Affiliation(s)
- A A Al-Mahrouki
- Department of Zoology and Division of Life Sciences, University of Toronto at Scarborough, Scarborough, Ont., M1C 1A4, Canada
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Sower SA, Suzuki K, Reed KL. Perspective: Research Activity of Enteropancreatic and Brain/Central Nervous System Hormones Across Invertebrates and Vertebrates1. ACTA ACUST UNITED AC 2000. [DOI: 10.1668/0003-1569(2000)040[0165:praoea]2.0.co;2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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