| First Author | Hjortebjerg R | Year | 2017 |
| Journal | Endocrinology | Volume | 158 |
| Issue | 5 | Pages | 1406-1418 |
| PubMed ID | 28323915 | Mgi Jnum | J:247027 |
| Mgi Id | MGI:5917155 | Doi | 10.1210/en.2017-00084 |
| Citation | Hjortebjerg R, et al. (2017) Insulin, IGF-1, and GH Receptors Are Altered in an Adipose Tissue Depot-Specific Manner in Male Mice With Modified GH Action. Endocrinology 158(5):1406-1418 |
| abstractText | Growth hormone (GH) is a determinant of glucose homeostasis and adipose tissue (AT) function. Using 7-month-old transgenic mice expressing the bovine growth hormone (bGH) gene and growth hormone receptor knockout (GHR-/-) mice, we examined whether changes in GH action affect glucose, insulin, and pyruvate tolerance and AT expression of proteins involved in the interrelated signaling pathways of GH, insulinlike growth factor 1 (IGF-1), and insulin. Furthermore, we searched for AT depot-specific differences in control mice. Glycated hemoglobin levels were reduced in bGH and GHR-/- mice, and bGH mice displayed impaired gluconeogenesis as judged by pyruvate tolerance testing. Serum IGF-1 was elevated by 90% in bGH mice, whereas IGF-1 and insulin were reduced by 97% and 61% in GHR-/- mice, respectively. Igf1 RNA was increased in subcutaneous, epididymal, retroperitoneal, and brown adipose tissue (BAT) depots in bGH mice (mean increase +/- standard error of the mean in all five depots, 153% +/- 27%) and decreased in all depots in GHR-/- mice (mean decrease, 62% +/- 4%). IGF-1 receptor expression was decreased in all AT depots of bGH mice (mean decrease, 49% +/- 6%) and increased in all AT depots of GHR-/- mice (mean increase, 94% +/- 8%). Insulin receptor expression was reduced in retroperitoneal, mesenteric, and BAT depots in bGH mice (mean decrease in all depots, 56% +/- 4%) and augmented in subcutaneous, retroperitoneal, mesenteric, and BAT depots in GHR-/- mice (mean increase: 51% +/- 1%). Collectively, our findings indicate a role for GH in influencing hormone signaling in AT in a depot-dependent manner. |
