MTOR: a possible Signaling Intermediate in the Leptin‐Kisspeptin Pathway during the Pubertal Transition in Female Rats

Abstract

While leptin and kisspeptin have both been implicated in the onset of puberty in mammals, the pathway linking leptin and kisspeptin is still not completely understood. Such knowledge could play an important role in treating or preventing infertility, both in humans, for the purpose of child bearing, and in other mammals, for agricultural reasons. Recent studies have suggested that mTOR, a ubiquitous serine/threonine kinase involved in cell and tissue growth and also a target of leptin signaling in the paraventricular and arcuate nuclei of the hypothalamus, may act as a signaling intermediate in the leptin‐kisspeptin pathway. Therefore, increases in mTOR in the hypothalamus may correlate with increases of leptin and kisspeptin in the hypothalamus as well. In this experiment, the gene expression of leptin, kisspeptin, and mTOR were examined using reverse‐transcriptase and polymerase chain reaction (RT‐PCR) from the hypothalami of female rats in ten day intervals beginning on postnatal day‐10 through postnatal day‐60. An increase in mTOR expression at day 40 correlated with increased expression in both leptin and kisspeptin. These findings suggest that mTOR could be involved in the leptin‐kisspeptin pathway and, therefore, the onset of puberty. This research was supported by a Lander University Foundation Grant.