Growth hormone (GH)/STAT5 signaling during the growth period in liver of mice overexpressing

MARTINEZ CS; PIAZZA VG; DÍAZ ME, GONZÁLEZ L, MIQUET JG, SOTELO AI, MARTÍNEZ CS, TURYN D.; BOPARAI RK; ARUM O; RAMÍREZ MC; GONZÁLEZ L; BECÚ-VILLALOBOS D; BARTKE A; TURYN D; MIQUET JG; SOTELO AI.

JOURNAL OF MOLECULAR ENDOCRINOLOGY

BIOSCIENTIFICA LTD

Lugar: Bristol; Año: 2015 vol. 54 p. 171 - 184

0952-5041

Growth hormone (GH)/STAT5 signaling is desensitized in liver of adult transgenic mice overexpressing GH; however, these animals present greater body size. To assess if the STAT5 pathway is active during the growth period in the liver of these animals, and how signaling modulators participate in this process, growing transgenic mice and normal siblings were evaluated. STAT5 does not respond to an acute GH-stimulus but presents higher basal phosphorylation in liver of growing GH-overexpressing mice. GH receptor and positive modulators GR and HNF1 display greater abundance in transgenic animals, supporting STAT5 activity. Negative modulators CIS and PTP1B are increased in GH-overexpressing mice. Suppressors SOCS2 and SOCS3 exhibit higher mRNA levels in transgenic mice but lower protein content, suggesting they are being degraded. Therefore, STAT5 signaling is increased in liver of GH-transgenic mice during the growth period, with a balance between positive and negative effectors resulting in an accelerated but controlled growth.