Time for a New Perspective on Prolactin in Metabolism

Area of Science:

• Endocrinology
• Metabolic Health
• Hormone Research

Background:

• The pituitary hormone prolactin (PRL) influences numerous functions, including metabolism.
• Historically, hyperprolactinemia was linked to metabolic dysfunction, suggesting a diabetogenic role.
• Recent large cohort studies challenge this view, associating low PRL with metabolic disease and type 2 diabetes (T2D).

Purpose of the Study:

• To re-evaluate the role of prolactin in metabolic homeostasis.
• To investigate the association between circulating PRL levels and metabolic health.
• To propose a revised understanding of physiological PRL levels in metabolic regulation.

Main Methods:

• Review and integration of basic science and clinical evidence.
• Analysis of findings from large cohort clinical studies on PRL levels and T2D.
• Examination of PRL's actions on key metabolic organs (pancreas, liver, adipose tissue, hypothalamus).

Main Results:

• Low circulating PRL levels are associated with metabolic disease and increased risk of T2D.
• Elevated PRL levels appear to be beneficial for metabolic health.
• PRL plays a crucial role in maintaining metabolic homeostasis across multiple tissues.

Conclusions:

• Upregulation of PRL levels is a key mechanism for maintaining metabolic homeostasis.
• The current range considered physiological for PRL may be too narrow.
• Higher PRL levels should be considered beneficial and potentially therapeutic for metabolic health.