Renske Kuppens

Promising effects of oxytocin on social and food-related behaviour in young children with Prader-Willi syndrome: a randomized, double-blind, controlled crossover trial.

Prader–Willi syndrome (PWS) is known for hyperphagia with impaired satiety and a specific behavioural phenotype with stubbornness, temper tantrums, manipulative and controlling behaviour and obsessive–compulsive features. PWS is associated with hypothalamic and oxytocinergic dysfunction. In humans without PWS, intranasal oxytocin administration had positive effects on social and eating behaviour, and weight balance.

Acylated and unacylated ghrelin during OGTT in Prader‐Willi syndrome: support for normal response to food intake

Prader‐Willi syndrome (PWS) is characterized by hyperphagia with impaired satiety. PWS patients have very high acylated ghrelin (AG) with normal unacylated ghrelin (UAG) levels, resulting in an elevated AG/UAG ratio, suggesting an intrinsic defect in the ghrelin regulation. Normally, food intake induces satiety and a drop in AG and UAG levels, but it is unknown if these levels also decline in PWS.

Metabolic health profile in young adults with Prader–Willi syndrome: results of a 2-year randomized, placebo-controlled, crossover GH trial

Patients with Prader–Willi syndrome (PWS) have an increased fat mass and decreased lean body mass. GH‐treated young adults with PWS who have attained adult height benefit from continuation of growth hormone (GH) treatment, as GH maintained their improved body composition, whereas fat mass increased during the placebo period. Adults with PWS are predisposed to T2DM and cardiovascular disease. Whether GH affects metabolic health profile of this patient group is unknown.

Bone mineral density in young adults with Prader-Willi syndrome: A randomized, placebo-controlled, crossover GH trial

The prevalence of osteoporosis is increased in adults with Prader‐Willi syndrome (PWS). In children with PWS, growth hormone (GH) treatment has beneficial effects on bone mineral density (BMD). BMD might deteriorate after cessation of GH at adult height (AH), while continuing GH might maintain BMD.

The Authors' Reply: Acylated and unacylated ghrelin during OGTT in Prader–Willi syndrome, a rebuttal to the conclusions by Kuppens et al.

1 Kuppens, R.J., Delhanty, P.J., Huisman, T.M. et al. (2016) Acylated and unacylated ghrelin during OGTT in Prader-Willi syndrome: support for normal response to food intake. Clinical Endocrinology (Oxford), doi:10.1111/cen.13036. [Epub ahead of print] 2 Gim enez-Palop, O., Gim enez-P erez, G., Mauricio, D. et al. (2007) A lesser postprandial suppression of plasma ghrelin in Prader-Willi syndrome is associated with low fasting and a blunted postprandial PYY response. Clinical Endocrinology (Oxford), 66, 198–204. 3 Purtell, L., Loughnan, G., Smith, E. et al. (2011) In adults with Prader-Willi syndrome elevated ghrelin levels are more consistent with hyperphagia that high PYY and GLP-1 levels. Neuropeptides, 45, 301–307. 4 DelParigi, A., Tschop, M., Heiman, M.L. et al. (2002) High circulating ghrelin: a potential cause for hyperphagia and obesity in Prader-Willi syndrome. Journal of Clinical Endocrinology and Metabolism, 87, 5461–5464. 5 Kuppens, R.J., Diene, G., Bakker, N.E. et al. (2015) Elevated ratio of acylated to unacylated ghrelin in children and young adults with Prader-Willi syndrome. Endocrine, 50, 633–642.