Molecular and Environmental Mechanisms Regulating Puberty Initiation: An Integrated Approach

Area of Science:

• Neuroendocrinology
• Reproductive Biology
• Developmental Biology

Background:

• Puberty initiation mechanisms remain incompletely understood.
• The hypothalamic GnRH pulse generation is a key hormonal trigger for puberty.
• The Kisspeptin-Neurokinin-Dynorphin (KNDy) system regulates GnRH secretion.

Purpose of the Study:

• To provide an integrated view of the mechanisms underlying puberty initiation.
• To highlight the roles of the KNDy system, upstream signals, and external factors.
• To discuss the influence of environmental factors and epigenetic modifications.

Main Methods:

• Review of accumulating evidence on puberty initiation.
• Analysis of the roles of KNDy neurons, GnRH pulse generation, and associated signaling pathways.
• Integration of data on external influences such as metabolic status, stress, and endocrine disruptors.

Main Results:

• The KNDy system, modulated by neurokinin B and dynorphin, is central to GnRH augmentation.
• Novel inhibitory signals like MKRN3 offer further insights into pubertal onset.
• Puberty onset is influenced by a complex interplay of central and peripheral factors, including metabolic and stress signals.
• Epigenetic modifications due to early life events and endocrine disruptors play a role.

Conclusions:

• Puberty initiation is a multifactorial process involving central neuroendocrine regulation and peripheral influences.
• The trigger for puberty is likely located upstream of the KNDy system and GnRH pulse generator.
• Environmental factors and early life experiences significantly impact pubertal timing through various mechanisms, including epigenetics.