Effects of ghrelin, growth hormone-releasing peptide-6, and growth hormone-releasing hormone on growth hormone, adrenocorticotropic hormone, and cortisol release in type 1 diabetes mellitus.
In type 1 diabetes mellitus (T1DM), growth hormone (GH) responses to provocative stimuli are normal or exaggerated, whereas the hypothalamic-pituitary-adrenal axis has been less studied. Ghrelin is a GH secretagogue that also increases adrenocorticotropic hormone (ACTH) and cortisol levels, similarly to GH-releasing peptide-6 (GHRP-6). Ghrelin's effects in patients with T1DM have not been evaluated. We therefore studied GH, ACTH, and cortisol responses to ghrelin and GHRP-6 in 9 patients with T1DM and 9 control subjects. The GH-releasing hormone (GHRH)-induced GH release was also evaluated. Mean fasting GH levels (micrograms per liter) were higher in T1DM (3.5 ± 1.2) than in controls (0.6 ± 0.3). In both groups, ghrelin-induced GH release was higher than that after GHRP-6 and GHRH. When analyzing Δ area under the curve (ΔAUC) GH values after ghrelin, GHRP-6, and GHRH, no significant differences were observed in T1DM compared with controls. There was a trend (P = .055) to higher mean basal cortisol values (micrograms per deciliter) in T1DM (11.7 ± 1.5) compared with controls (8.2 ± 0.8). No significant differences were seen in ΔAUC cortisol values in both groups after ghrelin and GHRP-6. Mean fasting ACTH values were similar in T1DM and controls. No differences were seen in ΔAUC ACTH levels in both groups after ghrelin and GHRP-6. In summary, patients with T1DM have normal GH responsiveness to ghrelin, GHRP-6, and GHRH. The ACTH and cortisol release after ghrelin and GHRP-6 is also similar to controls. Our results suggest that chronic hyperglycemia of T1DM does not interfere with GH-, ACTH-, and cortisol-releasing mechanisms stimulated by these peptides.
de Sá
Larissa Bianca Paiva Cunha
LB
Division of Endocrinology, Universidade Federal de São Paulo, UNIFESP-EPM, Rua Pedro de Toledo 910, 04039-002-São Paulo, Brazil. larissabianca_cunha@hotmail.com
Nascif
Sergio Oliva
SO
Correa-Silva
Silvia Regina
SR
Molica
Patricia
P
Vieira
José Gilberto Henriques
JG
Dib
Sergio Atala
SA
Lengyel
Ana-Maria Judith
AM
D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000328:Adult; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000378:metabolism*; D005260:Female; D054439:Ghrelin / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D013007:Growth Hormone-Releasing Hormone / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007262:Infusions, Intravenous; D008297:Male; D009842:Oligopeptides / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D013997:Time Factors; D055815:Young Adult
D054439:Ghrelin; D009842:Oligopeptides; D019382:Human Growth Hormone; C041048:growth hormone releasing hexapeptide; D000324:Adrenocorticotropic Hormone; D013007:Growth Hormone-Releasing Hormone; D006854:Hydrocortisone