ACTH and its role in immune-neuroendocrine functions. A comparative study

Area of Science:

• Neuroendocrinology
• Immunology
• Evolutionary Biology

Background:

• Adrenocorticotropic hormone (ACTH) is part of the melanocortin peptide family, derived from the pro-opiomelanocortin (POMC) precursor.
• Melanocortins exert effects via specific G-protein coupled receptors, with five subtypes currently identified.
• The POMC gene and ACTH are highly conserved throughout evolution, found in organisms from invertebrates to humans.

Purpose of the Study:

• To investigate the conserved role of ACTH in immune regulation across different life forms.
• To explore the evolutionary maintenance of the relationship between the immune and neuroendocrine systems.
• To highlight ACTH's function in immune responses and stress adaptation.

Main Methods:

• Review of existing literature on ACTH, POMC, melanocortin receptors, and their functions.
• Comparative analysis of ACTH's presence and roles in immune cells of invertebrates and vertebrates.
• Examination of ACTH's involvement in immune processes like chemotaxis and phagocytosis.

Main Results:

• ACTH and melanocortin receptors are present in immuno-competent cells of both invertebrates and vertebrates.
• ACTH significantly influences immune responses, including chemotaxis and phagocytosis, in diverse species.
• The stress response cascade involving ACTH in vertebrates is mirrored in invertebrate immunocytes.

Conclusions:

• ACTH functions as a significant immuno-regulator with an evolutionarily conserved role.
• ACTH is integral to the interconnectedness of the immune and neuroendocrine systems, a relationship largely preserved over evolutionary time.
• ACTH's involvement in immune function and stress response highlights its fundamental importance across the animal kingdom.