Effect of Central Antileptin Antibody on the Onset of Female Rat Puberty

Abstract

The effect of intracerebroventricular (ICV) antileptin antibody on the onset of puberty in the female rat and the relationship between serum leptin, luteinizing hormone (LH), and body weight were investigated. Antileptin antibody (group A) was infused ICV from days 23–36 in prepubertal female rats whereas the control (group B) received ICV goat immunoglobulin G (IgG). In the antileptin group, mean day of vaginal opening (VO) was postponed (day 34 versus day 30, P < .01 ). Body weight trended higher after 30 days in the antileptin group but not significantly. However, there was no difference in serum leptin and LH between the two groups on the day of VO. Serum leptin was relatively constant from day 23 through day 31 and did not correlate with LH (r = 0.14, P = .10). These studies demonstrate that central leptin promotes the onset of female rat puberty as evidenced by VO. Finally, central leptin impacts female rat pubertal onset in distinction from serum leptin and body weight.

Leptin as a Modulator of Neuroendocrine Function in Humans

“…These data in the extremely rare subjects with congenital leptin deficiency are consistent with our finding that a rise in leptin levels precedes the onset of puberty in normal boys 57. Even in rodents, exogenous leptin administration results in earlier onset of markers of puberty including vaginal opening,58 and leptin antibodies appear to inhibit pubertal onset in female rats 59. Although ob/ob mice have complete leptin deficiency and are infertile, female ob/ob mice can ovulate and give birth if they are treated with leptin in replacement doses,60 which stimulates the secretion of luteinizing hormone (LH) in vivo 61.…”

“… 57 Even in rodents, exogenous leptin administration results in earlier onset of markers of puberty including vaginal opening, 58 and leptin antibodies appear to inhibit pubertal onset in female rats. 59 Although ob/ob mice have complete leptin deficiency and are infertile, female ob/ob mice can ovulate and give birth if they are treated with leptin in replacement doses, 60 which stimulates the secretion of luteinizing hormone (LH) in vivo . 61 In mice, fasting-induced hypoleptinemia also diminishes the levels of gonadotropins and impairs the reproductive function and sex hormone levels of these mice; however, leptin administration restores testosterone levels in male mice, estrous cycles in female mice, and LH levels in both.…”

Associations of Obesity With Growth and Puberty in Children: A Cross-Sectional Study in Fuzhou, China

“…Several potential mechanisms could explain the link between childhood obesity and early pubertal onset. Obesity has been proposed as a activated metabolic gatekeeper of puberty, one of the key factors mediating this effect of obesity on puberty may be related to adipokines, especially leptin [ 41 ], which can directly stimulate gonadotropin secretion. In addition, the association between childhood obesity and early puberty may be related to the status of hyperinsulinemia/insulin resistance associated with obesity and the genetic polymorphism of obesity [ 42 ].…”