{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T14:03:01Z","timestamp":1775829781642,"version":"3.50.1"},"reference-count":0,"publisher":"Bioscientifica","issue":"1","content-domain":{"domain":["joe.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1993,1]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n        <jats:p>Although GH is known to regulate somatic growth during development, its role in regulating adult body composition is less well defined. The effects of GH on individual body compartments \u2013 water, fat, protein and mineral \u2013 are achieved both by the action of GH and by a GH-induced hormone, insulin-like growth factor-I (IGF-I). We used a genetic model of GH deficiency, the 'little' (gene symbol <jats:italic>lit<\/jats:italic>) mouse, to determine the GH regulation of IGF-I and its insulin-like growth factor-binding proteins (IGFBPs) and to define the interaction between these hormones and each body compartment in adults.<\/jats:p>\n        <jats:p>Our results showed that GH-deficient <jats:italic>lit\/lit<\/jats:italic> mice had reduced levels of serum IGF-I (range 38\u2013130 \u03bcg\/l) compared with normal <jats:italic>lit<\/jats:italic>\/+ littermates (range 432\u2013567 \u03bcg\/l) between 2 and 52 weeks of age. The <jats:italic>lit\/lit<\/jats:italic> mice did not experience the fivefold increase in IGF-I between 2 and 4 weeks of age that was seen in <jats:italic>lit<\/jats:italic>\/+ mice. In <jats:italic>lit\/lit<\/jats:italic> serum, overall binding of <jats:sup>125<\/jats:sup>I-labelled IGF-I to the four IGFBPs was reduced, solely in response to a reduced amount of IGFBP-3. No overall differences were found between <jats:italic>lit\/lit<\/jats:italic> and <jats:italic>lit<\/jats:italic>\/+ mice in the binding of <jats:sup>125<\/jats:sup>I-labelled IGF-I to IGFBP-2, -1 or -4. Age-related declines in IGF-I and IGFBPs were seen in <jats:italic>lit\/lit<\/jats:italic> mice. However, adult levels of IGF-I were maintained in <jats:italic>lit<\/jats:italic>\/+ mice to at least 52 weeks of age, as were levels of IGFBP-1 and -4, while IGFBP-3 and -2 declined with age.<\/jats:p>\n        <jats:p>With respect to body composition, comparison of <jats:italic>lit\/lit<\/jats:italic> with <jats:italic>lit<\/jats:italic>\/+ mice showed that the <jats:italic>lit\/lit<\/jats:italic> mice were characterized by abnormally large adipose tissue stores and reduced body water, protein and mineral from 2 weeks onward. These changes occurred despite normal energy intake in <jats:italic>lit\/lit<\/jats:italic> mice up to 52 weeks of age, indicating that neither undernutrition nor hyperphagia is characteristic of this GH-induced model of obesity. Furthermore, <jats:italic>lit\/lit<\/jats:italic> males accrued more body fat beginning at an earlier age than <jats:italic>lit\/lit<\/jats:italic> females. With advancing age, the per cent body fat increased in both <jats:italic>lit\/lit<\/jats:italic> and <jats:italic>lit<\/jats:italic>\/+ mice, while the per cent body water and mineral declined. In <jats:italic>lit\/lit<\/jats:italic> but not <jats:italic>lit<\/jats:italic>\/+ mice, per cent protein also declined with age. The changes in body water and fat are attributable to lack of adequate GH in the genetically GH-deficient <jats:italic>lit\/lit<\/jats:italic> mouse. On the other hand, the changes in body protein are more likely to be effects of IGF-I. Changes in mineral observed in <jats:italic>lit\/lit<\/jats:italic> mice could be the result of action by GH, IGF-I or both hormones. Therefore, when GH is chronically manipulated by GH deficiency as in <jats:italic>lit\/lit<\/jats:italic> mice, by GH excess as in acromegaly, or by GH therapy, all four body compartments are affected, suggesting that GH therapy is most valuable when the treatment goal is to alter overall body composition.<\/jats:p>\n        <jats:p><jats:italic>Journal of Endocrinology<\/jats:italic> (1993) <jats:bold>136,<\/jats:bold> 91\u2013104<\/jats:p>","DOI":"10.1677\/joe.0.1360091","type":"journal-article","created":{"date-parts":[[2008,12,11]],"date-time":"2008-12-11T23:11:46Z","timestamp":1229037106000},"page":"91-104","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-5","source":"Crossref","is-referenced-by-count":139,"title":["Growth hormone deficiency in 'little' mice results in aberrant body composition, reduced insulin-like growth factor-I and insulin-like growth factor-binding protein-3 (IGFBP-3), but does not affect IGFBP-2, -1 or -4"],"prefix":"10.1530","volume":"136","author":[{"given":"L. R.","family":"Donahue","sequence":"first","affiliation":[]},{"given":"W. G.","family":"Beamer","sequence":"additional","affiliation":[]}],"member":"416","container-title":["Journal of Endocrinology"],"original-title":[],"link":[{"URL":"https:\/\/joe.bioscientifica.com\/view\/journals\/joe\/136\/1\/joe_136_1_012.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/joe.bioscientifica.com\/downloadpdf\/journals\/joe\/136\/1\/joe_136_1_012.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,1,4]],"date-time":"2021-01-04T22:50:07Z","timestamp":1609800607000},"score":1,"resource":{"primary":{"URL":"https:\/\/joe.bioscientifica.com\/view\/journals\/joe\/136\/1\/joe_136_1_012.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,1]]},"references-count":0,"journal-issue":{"issue":"1"},"URL":"https:\/\/doi.org\/10.1677\/joe.0.1360091","relation":{},"ISSN":["0022-0795","1479-6805"],"issn-type":[{"value":"0022-0795","type":"print"},{"value":"1479-6805","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,1]]}}}