Enhanced Pulsatile Growth Hormone Secretion and Altered Metabolic Hormones by in Vivo Hexarelin Treatment in Streptozotocin-Induced Diabetic Rats.
Int J Mol Sci
; 19(10)2018 Oct 08.
Article
em En
| MEDLINE
| ID: mdl-30297647
ABSTRACT
Significant growth hormone (GH) reductions have been reported in diabetic animal models with disturbed metabolic balance coinciding with GH deficiency. Therefore, enhanced GH secretion may have beneficial effects in controlling diabetes. Thus, we aim to investigate the effect of hexarelin, a synthetic GH secretagogue (GHS), on GH secretion in streptozotocin (STZ, 65 mg/kg)-induced diabetic rats. Daily hexarelin (100 µg/kg) treatment was performed for two weeks in four-week-long STZ-diabetic and vehicle control rats. Pulsatile GH secretion in STZ-rats was significantly reduced in total, pulsatile, basal, and mass of GH secretion per burst. In addition, impaired GH secretion was followed by an increase in fasting-level free fatty acids (FFAs) and a decrease in insulin-like growth factor 1 (IGF-1) compared to control rats. After hexarelin treatment, pulsatile GH secretion in STZ-rats was significantly increased in total, pulsatile, and basal, but not in the mass GH secretion per burst, compared to STZ-rats without hexarelin treatment. However, there was no significant elevation in GH secretion in the hexarelin-treated control group. In addition, hexarelin-treated STZ-rats showed a significant decrease in fasting level FFAs, whereas suppression of fasting level for IGF-1 was maintained. These results suggest that STZ-induced diabetic rats have impaired pulsatile GH secretion, causing increased FFAs and decreased IGF-1 levels in circulation. Hexarelin injections for two weeks is able to normalize impaired pulsatile GH secretion with normal fasting levels of FFAs, but fails to recover IGF-1 levels.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligopeptídeos
/
Hormônio do Crescimento
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Substâncias de Crescimento
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Diabetes Mellitus Experimental
/
Secretagogos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Int J Mol Sci
Ano de publicação:
2018
Tipo de documento:
Article