Insulin-like growth factor II (IGF-II) mRNA expression during skeletal muscle development of double-muscled and normal bovine foetuses

The effect of insulin-like growth factor II (IGF II) on the rates of lactate formation, glycogen synthesis and glucose transport in the presence of a range of concentrations of insulin were investigated using an isolated preparation of rat skeletal muscle. IGF II, at a concentration of 65 ng/ml, caused a small but significant increase in the rates of these processes at a basal physiological insulin concentration (10 muunits/ml), but was without effect in the presence of 1, 100, 1000 or 10,000 muunits of insulin/ml. Hence IGF II increased the insulin sensitivity of this tissue. This effect was removed if the incubation medium was supplemented with an equimolar concentration of IGF binding protein 1 (BP1). It is suggested that changes in the concentration of IGF II and/or BP1 may regulate glucose uptake and metabolism in skeletal muscle and have physiological significance in the control of blood glucose level.

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Ribonucleic Acid Expression of the Clustered Imprinted Genes, p57KIP2, Insulin-Like Growth Factor II, and H19, in Adrenal Tumors and Cultured Adrenal Cells1

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jcem.82.6.3968 ◽

1997 ◽

Vol 82 (6) ◽

pp. 1766-1771 ◽

Cited By ~ 1

Author(s):

Jianqi Liu ◽

Arvi I. Kahri ◽

Päivi Heikkilä ◽

Raimo Voutilainen

Keyword(s):

Growth Factor ◽

Tumor Suppressor ◽

Mrna Expression ◽

Ribonucleic Acid ◽

Imprinted Genes ◽

Rna Expression ◽

Insulin Like Growth Factor ◽

Putative Tumor Suppressor ◽

Factor Ii ◽

Adrenocortical Carcinomas

Abstract The recently cloned cyclin-dependent kinase inhibitor gene p57KIP2 is genomically imprinted and located on human chromosome 11p15.5. This region contains two other imprinted genes, insulin-like growth factor II (IGF-II) and H19, both of which seem to be implicated in adrenal neoplasms. We analyzed the expression of the putative tumor suppressor p57KIP2 gene by Northern blotting in normal and hyperplastic adrenals, adrenocortical tumors, and pheochromocytomas. The expression of p57KIP2 messenger ribonucleic acid (mRNA) correlated positively with H19 and negatively with IGF-II RNA in adrenocortical tissues. p57KIP2 mRNA (and H19 RNA) was abundantly expressed in normal human adrenals, adrenocortical adenomas from patients with Cushing’s or Conn’s syndrome or without clinical evidence of hormone overproduction, hyperplastic adrenals, and tumor-adjacent adrenal tissues, in which IGF-II mRNA expression was low. In most adrenocortical carcinomas and virilizing adrenal adenomas, very low levels of both p57KIP2 and H19 RNAs were observed, whereas IGF-II was highly expressed. In pheochromocytomas, p57KIP2 and H19 RNA expression was highly variable, but on the average it was about 45% and 27%, respectively, of that in normal and tumor-adjacent adrenals. In cultured adrenocortical cells, ACTH and dibutyryl cAMP treatment slightly reduced the predominant 1.7-kilobase (kb) transcript of p57KIP2 gene, but induced a 2.5-kb transcript with a simultaneous increase in H19 RNA expression. The stimulatory effect of ACTH on the 2.5-kb p57KIP2 and H19 transcript accumulation was enhanced by exogenous IGF-II and IGF-I. Our data show that p57KIP2 and H19 RNAs are expressed usually in parallel in normal and pathological adrenocortical tissues. The decreased expression of both p57KIP2 and H19 RNAs in conjunction with elevated IGF-II mRNA expression in hormonally active adrenocortical carcinomas suggests that the loss of expression of the putative tumor suppressor genes p57KIP2 and H19 may be involved in the pathogenesis of these neoplasms.

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A new 5′-non-coding region for human placental insulin-like growth factor II mRNA expression

FEBS Letters ◽

10.1016/0014-5793(87)80216-8 ◽

1987 ◽

Vol 222 (1) ◽

pp. 181-185 ◽

Cited By ~ 21

Author(s):

Y. Le Bouc ◽

P. Noguiez ◽

P. Sondermeijer ◽

D. Dreyer ◽

F. Girard ◽

...

Keyword(s):

Growth Factor ◽

Mrna Expression ◽

Insulin Like Growth Factor ◽

Coding Region ◽

Factor Ii

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Viral expression of insulin-like growth factor-I isoforms promotes different responses in skeletal muscle

Journal of Applied Physiology ◽

10.1152/japplphysiol.01405.2005 ◽

2006 ◽

Vol 100 (6) ◽

pp. 1778-1784 ◽

Cited By ~ 81

Author(s):

Elisabeth R. Barton

Keyword(s):

Skeletal Muscle ◽

Growth Factor ◽

Muscle Mass ◽

Muscle Hypertrophy ◽

Muscle Development ◽

Muscle Size ◽

Insulin Like Growth Factor ◽

Factor I ◽

Igf I ◽

Growth Factor I

Insulin-like growth factor I (IGF-I) is a critical protein for skeletal muscle development and regeneration. Its ability to promote skeletal muscle hypertrophy has been demonstrated by several methods. Alternative splicing of the Igf-1 gene does not affect the mature IGF-I protein but does produce different E peptide extensions, which have been reported to modify the potency of IGF-I. Viral-mediated delivery of murine IGF-IA and IGF-IB into skeletal muscle of 2-wk-old and 6-mo-old mice was utilized to compare the effects of the isoforms on muscle mass. In young mice, tissue content of IGF-I protein was significantly higher in rAAV-treated muscles than control muscles at 1, 2, and 4 mo postinjection. Viral injection of IGF-IB produced two- to sevenfold more IGF-I than rAAVIGF-IA. Hypertrophy was observed 2 and 4 mo postinjection, where both rAAVIGF-IA and rAAVIGF-IB were equally effective in increasing muscle mass. These results suggest that there is a threshold of IGF-I production necessary to promote muscle hypertrophy in young growing animals regardless of isoform. In 6-mo-old animals, only rAAVIGF-IA produced significant increases in muscle size, even though increased IGF-I content was observed after injection of both isoforms. Therefore, the ability for IGF-IB to promote muscle hypertrophy is only effective in growing animals, suggesting that the bioavailability of this isoform or its receptor affinity diminishes with age.

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Interaction of multiplication stimulating activity/rat insulin-like growth factor II with skeletal muscle satellite cells during aging

Mechanisms of Ageing and Development ◽

10.1016/0047-6374(87)90003-0 ◽

1987 ◽

Vol 39 (2) ◽

pp. 121-128 ◽

Cited By ~ 31

Author(s):

Michael V. Dodson ◽

Ronald E. Allen

Keyword(s):

Skeletal Muscle ◽

Growth Factor ◽

Satellite Cells ◽

Insulin Like Growth Factor ◽

Muscle Satellite Cells ◽

Skeletal Muscle Satellite Cells ◽

Factor Ii

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Expression patterns of PPARγ2, PGC-1α, and MEF2C and their association with intramuscular fat content and skeletal muscle tenderness of crossbred Simmental bulls

Canadian Journal of Animal Science ◽

10.1139/cjas-2017-0165 ◽

2019 ◽

Vol 99 (2) ◽

pp. 367-376

Author(s):

Li-Qin Yang ◽

Jian Li ◽

Chun Wang ◽

Qiu-Ying Wu ◽

Xuan-Yu Chen ◽

...

Keyword(s):

Skeletal Muscle ◽

Mrna Expression ◽

Shear Force ◽

Muscle Development ◽

Expression Patterns ◽

Intramuscular Fat ◽

Skeletal Muscle Development ◽

Muscle Tenderness ◽

Imf Content ◽

Intramuscular Fat Content

PPARγ2, PGC-1α, and MEF2C play an important role in skeletal muscle development and fat deposition. This study aimed to determine their mRNA expression levels in longissimus dorsi (Ld), semitendinosus (Se), and soleus (Sol) muscles of crossbred Simmental bulls and estimate their association with intramuscular fat (IMF) content and meat shear force (MSF). We measured the muscle fiber (MF) density and area, IMF content, and MSF of 6-, 12-, and 36-mo-old bulls. We found that the expression patterns differed with age: the PPARγ2 expression in the three muscles of 36-mo-old bulls was greater than that in the muscles of 6- and 12-mo-old bulls (P < 0.05). Furthermore, PGC-1α expression in Sol of 36-mo-old and MEF2C expression in Ld of 12-mo-old bulls were higher than those in the respective muscles of 6- and 12-mo-old bulls, and 6- and 36-mo-old bulls, respectively (P < 0.05). The MF area, IMF content, and MSF increased with age (P < 0.05). The PPARγ2 mRNA expression in Ld, Se, and Sol was positively correlated with MF area and IMF content (P < 0.05) and negatively correlated with MF density (P < 0.05). Thus, PPARγ2 might be a candidate marker, which is positively correlated with IMF content and MF area.

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