Changes in the Immune–Endocrine Interrelationships in Anxiety and Depression

Abstract

Evidence from clinical studies suggests that chronic exposure to physical and/or psychological stress profoundly affects the mental state and may be causally involved in anxiety and depressive disorders. Corticotropin releasing factor (CRF), which is released by any stressor, is known to regulate peripheral glucocorticoid function and also to influence central neurotransmitter activity by activating specific CRF receptors located in limbic regions of the brain. Whereas peptides other than CRF undoubtedly play a role in the peripheral and central changes initiated by stress, it would appear that the CRF plays a central role in orchestrating these changes. Besides the alterations in endocrine and neurotransmitter function that are characteristic of anxiety states and major depressive disorders, it is also known that the immune system is profoundly disturbed in these conditions. Psychoneuroimmunology has developed as a speciality to explain the link between the immune, endocrine and neurotransmitter systems. This review summarizes the evidence which suggests that severe anxiety and depression may be considered as a maladaptation to chronic stress in which the immune and endocrine systems play a principal role. Such a hypothesis may enable new types of anti‐anxiety and antidepressant drugs to be developed which act on the underlying maladapted endocrine and immune processes that cause the neurotransmitter malfunction which characterize these disorders. © 1997 John Wiley & Sons, Ltd.

Peripheral markers of depression

“…Furthermore, the cytokines released from immune cells can affect the brain and cause behavioural changes, some of which are similar to those that occur in depression. This area has been the subject of recent reviews [40,41]. Whereas immunosuppression, as indicated by a reduction in natural killer cell activity and in T-cell proliferation, may be of a consequence of hypercortisolaemia that usually occurs in depression, there is also evidence that some aspects of cellular immunity are hyperactive in these patients.…”

Psychophysiological Mediators of Caregiver Stress and Differential Cognitive Decline.

“…Potential psychosocial mediators are anxiety, depression, and hostility. Anxiety and depression are positively associated with chronic stress (Korte, 2001; Leonard & Song, 1997; Norris & Uhl, 1993) and negatively associated with cognitive functioning (Kizilbash, Vanderploeg, & Curtiss, 2002; Sinoff & Werner, 2003). Hostility is positively related to both chronic stress (Steptoe & Marmot, 2003) and lower metabolism in the prefrontal cortex (Shapiro et al, 2000).…”