The use of recombinant gilthead sea bream (Sparus aurata) growth hormone for radioiodination and standard preparation in radioimmunoassay

Martı́nez-Barberá, Juan Pedro; Pendón, Carlos; H, Martí-Palanca; Calduch-Giner, Josep Àlvar; Rodríguez, Ramón B.; Valdivia, Manuel M.; Pérez‐Sánchez, Jaume

doi:10.1016/0300-9629(94)00178-v

Cited by 36 publications

(19 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hormones used were as follows: porcine insulin (10 and 100 nM) from Sigma (Madrid, Spain); porcine glucagon (10 and 100 nM) from Sigma; and recombinant gilthead seabream GH (0.1-10 nM), produced as described elsewhere (18).…”

Section: Methodsmentioning

confidence: 99%

Nutritional and hormonal control of lipolysis in isolated gilthead seabream (Sparus aurata) adipocytes

Albalat¹,

Gómez‐Requeni²,

Rojas³

et al. 2005

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

-We examined the effects of diet composition and fasting on lipolysis of freshly isolated adipocytes from gilthead seabream (Sparus aurata). We also analyzed the effects of insulin, glucagon, and growth hormone (GH) in adipocytes isolated from fish fed with different diets. Basal lipolysis, measured as glycerol release, increased proportionally with cell concentration and time of incubation, which validates the suitability of these cell preparations for the study of hormonal regulation of this metabolic process. Gilthead seabream were fed two different diets, FM (100% of fish meal) and PP (100% of plant protein supplied by plant sources) for 6 wk. After this period, each diet group was divided into two groups: fed and fasted (for 11 days). Lipolysis was significantly higher in adipocytes from PP-fed fish than in adipocytes from FM-fed fish. Fasting provoked a significant increase in the lipolytic rate, about threefold in isolated adipocytes regardless of nutritional history. Hormone effects were similar in the different groups: glucagon increased the lipolytic rate, whereas insulin had almost no effect. GH was clearly lipolytic, although the relative increase in glycerol over control was lower in isolated adipocytes from fasted fish compared with fed fish. Together, we demonstrate for the first time that lipolysis, measured in isolated seabream adipocytes, is affected by the nutritional state of the fish. Furthermore, our data suggest that glucagon and especially GH play a major role in the control of adipocyte lipolysis.fish; nutritional and hormonal regulation; insulin; glucagon; growth hormone; fasting ADIPOSE TISSUE PLAYS A CENTRAL role in energy homeostasis in storing lipids in the form of triacylglycerols and in mobilizing them via breakdown into free fatty acids (FFAs) and glycerol (34). Adipose tissue is one of the most important lipid stores in several teleosts, although in some species liver or muscle also constitutes lipid storage organs (33). In salmonids, adipose tissue is distributed primarily in the abdominal cavity, associated with the mesenteric and pyloric ceca (31). In gilthead seabream, adipose tissue is also located periviscerally. It is known that fish adiposity changes seasonally and is affected by trophic status. High-fat feeds can lead to increases in visceral fat (4), resulting in reduced product yield and quality of cultured fish (7). In gilthead seabream, replacing fish meal with plant protein seems to alter lipid metabolism and results in smaller fat depots (10).Endocrine control of adipose tissue mobilization and storage remains almost unexplored in fish, although insulin and glucagon are clearly involved (12,24,28). Key hepatic enzymes in lipid metabolism such as hepatic lipase and acetyl-CoA carboxylase are also regulated by pancreatic hormones in vitro in isolated hepatocytes or in vivo in injected fish (13,21). Several in vivo studies suggest that growth hormone (GH) and somatolactin act together, in a complementary way, to regulate fat stores in gilthead seabream (4, 20). Howev...

show abstract

Section: Methodsmentioning

confidence: 99%

Nutritional and hormonal control of lipolysis in isolated gilthead seabream (Sparus aurata) adipocytes

Albalat¹,

Gómez‐Requeni²,

Rojas³

et al. 2005

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

show abstract

“…Plasma GH levels were determined by a homologous gilthead sea bream RIA as reported elsewhere (Martínez-Barberá et al 1995). The sensitivity and midrange (ED50) of the assay were 0 .…”

Section: Hormone Assaysmentioning

confidence: 99%

Co-expression of IGFs and GH receptors (GHRs) in gilthead sea bream (Sparus aurata L.): sequence analysis of the GHR-flanking region

Saera-Vila¹,

Calduch-Giner²,

Pérez‐Sánchez

2007

Journal of Endocrinology

View full text Add to dashboard Cite

The tissue-specific expression of IGFs and GH receptors (GHRs) was analyzed in gilthead sea bream (Sparus aurata L.) as an attempt to understand the functional partitioning of duplicated GHRs on the regulation of fish growth by season and aging. Gene transcripts were measured in liver, muscle, and adipose tissue by means of quantitative real-time PCR assays. In juvenile fish, concurrent increases in circulating levels of GH and IGF-I and hepatic mRNA levels of IGF-I and GHR-I were evidenced with the summer growth spurt. Conversely, muscle and adipose tissue expression of GHR-I and IGF-II were significantly upregulated by overwintering. The aging decrease of growth rates was accompanied by a reduced activity of the liver GH/IGF axis, and parallel increases in muscle IGF expression would be dictated at the local tissue level by the enhanced expression of GHR-I. Extra-hepatic expression of IGFs and GHR-II did not correlate seasonally in juvenile fish, and nonsignificant effects of aging were found on the summer expression of GHR-II in any analyzed tissue. One transcription start site was identified by RLM-RACE in GHR-I and GHR-II. Sequence analyses indicated that both genes have TATA-less promoters containing consensus initiator sequences and downstream promoter elements surrounding the transcription start site. Conserved CCAAT-boxes and GC-rich regions were retrieved in the GHR-I promoter, whereas stress-and redoxsequence elements (cAMP-responsive element-binding protein, activator proteins; AP-1, and AP-4) were characteristic features of GHR-II. All this supports the functional partitioning of fish GHRs regardless of fish species differences.

show abstract

“…Plasma GH levels were determined by a homologous gilthead sea bream radioimmunoassay (RIA) as reported elsewhere (Martínez-Barberá et al, 1995). The sensitivity and midrange (ED 50 ) of the assay were 0.15 and 1.5-2 ng/mL, respectively.…”

Section: Circulating Hormone and Lipid Profilesmentioning

confidence: 99%

Feed restriction up-regulates uncoupling protein 3 (UCP3) gene expression in heart and red muscle tissues of gilthead sea bream (Sparus aurata L.)

Bermejo-Nogales

Benedito-Palos

Calduch-Giner

et al. 2011

Comparative Biochemistry and Physiology Part A: Molecular &

Self Cite

View full text Add to dashboard Cite

The physiological regulation of the mitochondrial uncoupling protein 3 (UCP3) remains practically unexplored in fish and the aim of this study was to examine the effects of ration size on the regulation of UCP3 in heart, red skeletal muscle and white skeletal muscle of gilthead sea bream (Sparus aurata L.). Juvenile fish were fed at three different levels for 11 weeks: i) full ration until visual satiety (R(100) group), ii) 70% of satiation (R(70) group) and iii) 70% of satiation with two finishing weeks at the maintenance ration (20% of the satiation level) (R(70-20) group). The thirty percent feed restriction improved fish performance, increasing feed conversion efficiency and circulating levels of insulin-like growth factor-I (IGF-I). Fish of the R(70-20) group showed reduced growth and low circulating levels of IGF-I in combination with increased circulating concentrations of growth hormone and free fatty acids. Feed restriction did not alter UCP3 transcript levels in white skeletal muscle, but improved this tissue's oxidative capacity as assessed by changes in glycolytic and oxidative mitochondrial enzyme activities. In contrast, in cardiac and red skeletal muscle tissues, this dietary treatment primarily increased UCP3 mRNA expression. The respiratory control ratio of freshly isolated heart mitochondria was slightly lower in R(70-20) fish than in R(100) fish, which suggests that there was an increase in mitochondrial uncoupling concomitant with the enhanced UCP3 mRNA expression. Altogether, these findings highlight the different adaptive mechanism of glycolytic and highly oxidative muscle tissues for their rapid adjustment to varying feed intake.

show abstract

The use of recombinant gilthead sea bream (Sparus aurata) growth hormone for radioiodination and standard preparation in radioimmunoassay

Cited by 36 publications

References 20 publications

Nutritional and hormonal control of lipolysis in isolated gilthead seabream (Sparus aurata) adipocytes

Nutritional and hormonal control of lipolysis in isolated gilthead seabream (Sparus aurata) adipocytes

Co-expression of IGFs and GH receptors (GHRs) in gilthead sea bream (Sparus aurata L.): sequence analysis of the GHR-flanking region

Feed restriction up-regulates uncoupling protein 3 (UCP3) gene expression in heart and red muscle tissues of gilthead sea bream (Sparus aurata L.)

Contact Info

Product

Resources

About