Endogeneous Signals and Mammalian Puberty Onset: A Review

One of the most important events in the life of mammals is the onset of puberty during which the secondary sexual characters appear, the growth increase until the final height is reached and fertility is achieved. The timing of puberty is precisely controlled by a plethora of endogenous signals and environmental cues that affect hypothalamic–pituitary–gonadal (HPG or Journal of Biology and Life Science ISSN 2157-6076 2015, Vol. 6, No. 1 www.macrothink.org/jbls 2 reproductive) axis at different levels. This phenomenon, which ensures that the tempo of puberty is adjusted to the internal and external conditions of the body, is also responsible for perturbations of its timing when such conditions are not optimal. Accordingly, puberty has been regarded not only as a fundamental developmental event, but also as sensor of the proper interplay between genes and environment along development.