Increase of serum leptin after short-term pulsatile GnRH administration in children with delayed puberty

Abstract

Objective: Leptin is known to play an important role in pubertal development in humans, probably acting as one permissive factor for the onset of puberty. Leptin serum concentrations change during pubertal development and an initial increase before the onset of puberty has been reported. The underlying mechanism for this increase in leptin levels is unknown. We hypothesized that the pulsatile release of GnRH stimulates leptin metabolism. In this study, the effect of short-term pulsatile GnRH administration on leptin levels in children with delayed onset of puberty was investigated. Methods: Nineteen children (15 males and four females, mean age 15.5 years, range 13.1 -20.5 years), who underwent evaluation for delayed sexual maturation, were included in the study. Sixteen subjects received 36 h of pulsatile intravenous GnRH, using an infusion pump that released 5 mg GnRH every 90 min. Serum concentrations of LH, FSH, testosterone, estradiol and leptin were analysed before and up to 36 h after GnRH administration. Eight patients received a single dose GnRH-agonist stimulation test (buserelin acetate test, 10 mg/kg body weight) with a 24-h followup (five patients underwent both tests). Results: Mean (^S.E.M.) serum leptin increased significantly (P, 0.01) after 36 h of pulsatile GnRH administration (7.26^1.35 vs 9.75^1.76 ng/ml). In contrast, no increase in leptin concentrations was observed after administration of a single dose of buserelin. Conclusions: These findings suggested that the increase in serum leptin at the onset of puberty is triggered by the pulsatile release of GnRH.European Journal of Endocrinology 150 691-698

Serum Leptin Concentration and Its Effect on Puberty in Naqu Tibetan Adolescents

“…GarciaMayor found that female puberty leptin concentrations steadily increase whereas in male puberty leptin concentrations only increase until approximately the age of 10 years, and then decrease with increasing testosterone levels (Garcia-Mayor et al, 1997). Interestingly, it has been shown that leptin levels peak before the onset of puberty in both sexes, suggesting a specific role for leptin at this point of puberty (Horlick et al, 2000;Mantzoros et al, 1997;Grasemann et al, 2004). Endocrinologist Jeffrey Flier of the Beth Israel Deaconess Medical Center in Boston proposed that leptin may even be the trigger for the onset of puberty (Vogel, 1996).…”

Parental Binge Alcohol Abuse Alters F1 Generation Hypothalamic Gene Expression in the Absence of Direct Fetal Alcohol Exposure

“…Another significant finding was the observed increase in GnRH mRNA expression in male offspring as a result of parental adolescent binge EtOH exposure. GnRH has long been known for stimulation of gonadotropin release from the pituitary gland in both males and females and therefore, is absolutely required for pubertal onset and fertility [43], [44], [45], [71], [72], [73], [74], [75], [76], [77], [78], [79], [80]. Recently, a role for GnRH in metabolic functions has been demonstrated by Harris and colleagues, who showed that GnRH increased the expression of the glucose transporter, GLU-1, in pituitary gonadotrophs and stimulated glucose uptake in these cells [81].…”

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