A dual-axis approach to understanding neuroendocrine development

Area of Science:

• Endocrinology
• Neuroendocrinology
• Psychoneuroendocrinology

Background:

• The traditional view posits that the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-gonadal (HPG) axis function in opposition.
• This special issue introduces the concept of 'coupling,' suggesting these axes can operate synergistically.

Discussion:

• Empirical evidence demonstrates a positive within-person association between stress hormones (e.g., cortisol) and sex hormones (e.g., testosterone).
• This coupling is observed across various timeframes (acute, diurnal, basal, longitudinal) and contexts.
• Sophisticated statistical models were employed to validate coupling as a within-person phenomenon and challenge the oppositional paradigm.

Key Insights:

• The consistency of observed coupling across studies supports challenging the prevailing oppositional view of the HPA and HPG axes.
• Positive coupling is evident in situations that are both stressful and challenging.
• Adolescence, a developmental stage characterized by significant stress, exemplifies contexts where these axes may function together.

Outlook:

• This work proposes a functional dual-axis approach to understanding the interplay between stress and sex hormone systems.
• Future research should explore the specific conditions and developmental stages where HPA-gonadal axis coupling is most prominent.
• This perspective aims to advance the field's understanding of when and how these crucial neuroendocrine axes collaborate.