Igf-I and postnatal growth of weaver mutant mice.

Abstract

IGF-I is an anabolic growth factor essential for growth and development, both as a mediator of growth hormone (GH) action and as a local stimulator of cell proliferation and differentiation. Although the importance of IGF-I in postnatal growth has been studied for several decades, its functions in pathological states are not fully understood. The weaver (wv) mutant mouse is a commonly used model for studying hereditary cerebellar ataxia and provides us with an opportunity to study the function of IGF-I in postnatal growth during neurodegeneration. In prepubertal wv mice, we found a parallel decrease in body weight and serum IGF-I. This parallel relationship was maintained in females, but not in males, as wv mice entered puberty. Interestingly, we found an increase in the levels of circulating IGF-I and hepatic mRNA preceded the catch-up of body weight of pubertal male wv mice. The increase in IGF-I levels coincided with a surge of circulating androgen at the onset of male puberty, suggesting that androgen might trigger the increase in IGF-I production in the pubertal and adult male wv mice. Overall, our results support the concept that IGF-I plays an important role in postnatal growth during and after neurodegeneration of wv mice. In addition, IGF-I's regulation of systemic growth during and after puberty is likely modulated by androgen in male wv mice.

• Authors: Weiguo Yao, Jin Zhong, Clifford J Rosen, Janet M Hock, Wei-Hua Lee
• Journal: Endocrine (Endocrine) Vol. 26 Issue 2 Pg. 117-25 (Mar 2005) ISSN: 1355-008X [Print] United States
• PMID: 15888923 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Insulin-Like Growth Factor Binding Protein 3
• RNA, Messenger
• Insulin-Like Growth Factor I

Topics

• Animals
• Blotting, Northern
• Blotting, Western
• Cerebellar Ataxia (metabolism, physiopathology)
• Female
• Insulin-Like Growth Factor Binding Protein 3 (biosynthesis, blood)
• Insulin-Like Growth Factor I (biosynthesis, genetics, physiology)
• Liver (metabolism)
• Male
• Mice
• Mice, Neurologic Mutants (growth & development, metabolism)
• RNA, Messenger (biosynthesis, genetics)
• Reverse Transcriptase Polymerase Chain Reaction
• Sex Factors
• Sexual Maturation (physiology)