Association of ghrelin and leptin with reproductive hormones in constitutional delay of growth and puberty

Abstract

BackgroundConstitutional delay of growth and puberty (CDGP) is a variation of the onset and timing of pubertal development without a defined endocrine abnormality. Recently published studies indicate that leptin and ghrelin play a role in puberty initiation and progress. They have been implicated in regulation of GnRH secretion, with ghrelin having inhibitory and leptin, facilitatory effects. We hypothesized that elevated ghrelin and reduced leptin concentrations could be implicated in altering the tempo of puberty in adolescents with CDGP. So in the current study we evaluate variations in leptin and ghrelin levels in adolescent boys with CDGP, the relationships between both hormones and reproductive hormones including LH, FSH and testosterone were also evaluated.MethodsThe study enrolled 23 adolescent boys with CDGP and 20 healthy controls matched for age and sex. Weight, height, BMI, testicular volume, bone age, bone age delay, serum FSH, LH, testosterone, leptin and ghrelin were assessed.ResultsAdolescent boys with CDGP had significantly lower leptin and higher ghrelin than normal controls. Leptin was positively correlated with BMI, bone age, testicular volume, FSH, LH and testosterone and negatively correlated with delayed bone age and ghrelin. Ghrelin was negatively correlated with BMI, bone age, testicular volume, FSH, LH and testosterone. With multiple regression analysis BMI, FSH, LH, testosterone and ghrelin remained independently correlated with leptin while BMI, LH and testosterone remained independently correlated with ghrelin.ConclusionElevated serum ghrelin and decreased leptin concentrations and their associations with reproductive hormones may explain the sexual immaturity in adolescent boys with CDGP.

The impact of adipose tissue-derived factors on the hypothalamic-pituitary-gonadal (HPG) axis

“…It now appears that an intermediate type of neurons, possessing leptin receptors, convey the adipose tissue/leptin message to GnRH-producing neurons. 28 Low leptin levels have been associated with sexual immaturity, 29,30 while it has been documented that the administration of leptin to female adolescents with endogenous leptin deficiency and hypogonadotropin hypogonadism triggers the onset of menarche. 31 The role of leptin in menarche is crucial.…”

Leptin Levels in Children and Adults with Classic Galactosaemia

“…However, leptin is positively correlated with BMI in healthy boys (El-Eshmawy et al 2010). Early puberty might be a particular vulnerable period in individuals at risk of decreased reproductive capacity.…”

“…Early puberty might be a particular vulnerable period in individuals at risk of decreased reproductive capacity. Along these lines, reduced leptin levels were found in adolescent boys with constitutional delay of growth and puberty (El-Eshmawy et al 2010). Additionally, decreased leptin and its impact on the reproductive axis may help to explain delayed pubertal development in adolescent boys with Gal and perhaps also cryptorchidism in some cases (Gubbels et al 2011b).…”

Ultrastructural study of spermatogenesis in KSR2 deficient mice

“…These data could represent the base for future development oriented to assess the hormonal status of these mice, particularly focussing on the levels of testosterone and dihydrotestosterone produced by Leydig cells. In addition, other paracrine regulators of Leydig cells including insulin-like factor 3, ghrelin and leptin (Svechnikov et al 2010) involved in food intake, obesity and reproductive activity (El-Eshmawy et al 2010) should be investigated. We are currently working on these hypotheses as part of a more extensive functional characterization of the overall hormonal status of the ksr2 -/-mice including the hormones involved in the hypothalamic-pituitarygonadal axis.…”