title: Insulin-like growth factor 1 is expressed in mouse developing testis and regulates somatic cell proliferation.
abstract: Testicular development occurs prenatally in mammals. The developmental underlying mechanism is only partially understood. The aim of the present investigation was to study the expression of the gene coding for insulin-like growth factor 1 (Igf-1) and Igf-1 type 1 receptor (Igf-1r) and their respective proteins in mouse Sertoli and Leydig cells at gestation day 12 (E12)-E18. Moreover, we sought to determine the effect of IGF-1 on the proliferation of both cell types and to establish the signal transduction mechanism involved in the IGF-1 pathway. Transcripts for the Igf-1 and Igf-1r genes were found in Sertoli and Leydig cells from E12-E18. Highest IGF-1 and IGF-Ir protein expression levels were found in both cell types at E18. Exogenous IGF-1 administration increased Sertoli and Leydig cell proliferation at E14-E18 in vitro. Inhibition of the pathway mitogen-activated extracellular signal-regulated protein kinase (MEK) 1/2 with UO126 diminished the proliferation of the Sertoli and Leydig cells in vitro. We propose that IGF-1 and IGF-1r regulate Sertoli and Leydig cell proliferation through the MEK/extracellular-signal-regulated kinase (ERK) 1/2 signal transduction pathway, leading to development and growth of the mouse embryonic testis.
authors: Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, UNAM, Apartado Postal 70228, México D.F 04510, Mexico. villalpando@biomedicas.unam.mx
authors: Irma
authors: I
authors: Villalpando
authors: Esmeralda
authors: E
authors: Lira
authors: Georgina
authors: G
authors: Medina
authors: Erick
authors: E
authors: Garcia-Garcia
authors: Olga
authors: O
authors: Echeverria
mesh_terms: D000818:Animals; D002070:Butadienes; D049109:Cell Proliferation; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism*; D048369:MAP Kinase Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048370:MAP Kinase Kinase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000502:physiology; D008297:Male; D051379:Mice; D009570:Nitriles; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D013737:Testis / Q000166:cytology / Q000196:embryology / Q000378:metabolism
chemical_list: D002070:Butadienes; D009570:Nitriles; D020033:Protein Isoforms; C113580:U 0126; D007334:Insulin-Like Growth Factor I; D048369:MAP Kinase Kinase 1; D048370:MAP Kinase Kinase 2