Metabolic profiling in Prader-Willi syndrome and non-syndromic obesity: sex differences and the role of growth hormone

OBJECTIVES:

To identify metabolic factors controlling appetite and insulin sensitivity in PWS and assess effects of GH treatment.

METHODS:

We compared amino acids, fatty acids, and acylcarnitines in GH-treated and untreated PWS children and obese and lean controls to identify biomarkers associated with ghrelin, peptide YY, and markers of insulin sensitivity (adiponectin and HOMA-IR).

RESULTS:

Compared with obese controls (OC), children with PWS had hyperghrelinemia, hyperadiponectinemia, hypoinsulinemia, and increased ghrelin/PYY. Hyperghrelinemia, hyperadiponectinemia, and hypoinsulinemia were more striking in PWS females than males and decreases in BCAA were detected only in PWS females. GH-treated PWS subjects had lower leptin and higher IGF-1 and adiponectin than untreated subjects; ghrelin, PYY, and insulin levels were comparable. Ghrelin correlated inversely with BCAA in PWS but not OC. Adiponectin correlated negatively with BMIz and HOMA-IR in PWS; in contrast, adiponectin correlated more strongly with BCAA than BMIz or HOMA-IR in OC.

CONCLUSIONS:

BCAA levels were lower in PWS females than OC females and correlated inversely with ghrelin. Low BCAA in PWS females may promote hyperghrelinemia and hyperphagia, while hyperadiponectinemia may maintain insulin sensitivity despite excess weight gain. GH treatment may reduce leptin and increase adiponectin, but does not affect ghrelin or PYY. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.

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