Elevated circulating IGF-I promotes mammary gland development and proliferation - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Accéder directement au contenu
Article Dans Une Revue Endocrinology Année : 2010

Elevated circulating IGF-I promotes mammary gland development and proliferation

Résumé

Animal studies have shown that IGF-I is essential for mammary gland development. Previous studies have suggested that local IGF-I rather than circulating IGF-I is the major mediator of mammary gland development. In the present study we used the hepatic IGF-I transgenic (HIT) and IGF-I knockout/HIT (KO-HIT) mouse models to examine the effects of enhanced circulating IGF-I on mammary development in the presence and absence of local IGF-I. HIT mice express the rat IGF-I transgene under the transthyretin promoter in the liver and have elevated circulating IGF-I and normal tissue IGF-I levels. The KO-HIT mice have no tissue IGF-I and increased circulating IGF-I. Analysis of mammary gland development reveals a greater degree of complexity in HIT mice as compared to control and KO-HIT mice, which demonstrate similar degrees of mammary gland complexity. Immunohistochemical evaluation of glands of HIT mice also suggests an enhanced degree of proliferation of the mammary gland, whereas KO-HIT mice exhibit mammary gland proliferation similar to control mice. In addition, HIT mice have a higher percentage of proliferating myoepithelial and luminal cells than control mice, whereas KO-HIT mice have an equivalent percentage of proliferating myoepithelial and luminal cells as control mice. Thus, our findings show that elevated circulating IGF-I levels are sufficient to promote normal pubertal mammary epithelial development. However, HIT mice demonstrate more pronounced mammary gland development when compared to control and KO-HIT mice. This suggests that both local and endocrine IGF-I play roles in mammary gland development and that elevated circulating IGF-I accelerates mammary epithelial proliferation.

Domaines

Autre [q-bio.OT]

Dates et versions

hal-02662728 , version 1 (31-05-2020)

Identifiants

Citer

Dara Cannata, Danielle Lann, Yingjie Wu, Sébastien Elis, Hui Sun, et al.. Elevated circulating IGF-I promotes mammary gland development and proliferation. Endocrinology, 2010, 151 (12), pp.5751-5761. ⟨10.1210/en.2010-0792⟩. ⟨hal-02662728⟩

Collections

INRAE
8 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More