The psychoneuroimmunology of depression

Abstract

Chronic stress, by initiating changes in the hypothalamic-pituitary-adrenal (HPA) axis and the immune system, acts as a trigger for anxiety and depression. There is experimental and clinical evidence that the rise in the concentration of pro-inflammatory cytokines and glucocorticoids, which occurs in a chronically stressful situation and also in depression, contribute to the behavioural changes associated with depression. A defect in serotonergic function is associated with these hormonal and immune changes. Neurodegenerative changes in the hippocampus, prefrontal cortex and amygdalae are the frequent outcome of the changes in the HPA axis and the immune system. Such changes may provide evidence for the link between chronic depression and dementia in later life.

Deficiency in Endocannabinoid Signaling in the Nucleus Accumbens Induced by Chronic Unpredictable Stress

“…Neither sub-CUS nor CUS had any significant effect on the serum levels of corticosterone (main effect stress: F(1, 28) ¼ 2.749, p40.05; main effect time: F(1, 28) ¼ 0.069, p40.05; stress  time interaction: F(1, 28) ¼ 0.405, p40.05; Table 1). Thus, the CUS paradigm used in the present study is effective, as it induced a sustained hyperactivity of the hypothalamuspituitary-adrenal axis and suppression of the immune system (Muscat and Willner, 1992;Kubera et al, 1995;Willner, 2005;Leonard and Myint, 2009). However, during the time of testing, the serum levels of corticosterone were unchanged in stress-exposed mice, indicating that CUSexposed mice did not have alterations in the level of basal glucocorticoids 2-7 days after the last stress exposure.…”

“…In addition to the behavioral profile exhibited, animals exposed to CUS show adrenal hypertrophy and thymus hypotrophy (Muscat and Willner, 1992;Kubera et al, 1995;Willner, 2005;Leonard and Myint, 2009). At 2-7 days after the last behavioral test, mice were killed, blood was collected, and adrenals and thymuses were excised and weighed immediately.…”

Clinical trial of adjunctive celecoxib treatment in patients with major depression: a double blind and placebo controlled trial

“…[9][10][11][12][13] All together, these studies suggest that COX-2 inhibitors could be developed as potential agents for the treatment of depression. [23][24][25][26][27] However, there is probably a spectrum of inflammation for patients with MDD and it would be useful to measure cytokines before and after treatment as a predictor and mediator of response to COX-2 inhibitors. [25,27] The limitations of this study, including the relatively small sample size and only a fixed dose of celecoxib, should be taken into account and this indicates the need for further research.…”

Care Partners and Multiple Sclerosis

“…34 Changes in immune function are also associated with psychiatric disorders, such as depression and anxiety. 35 Negative emotions and stressful experiences collectively can lead to physiologic inflammation, which has also been associated with a variety of deleterious health effects, including cardiovascular disease, diabetes, and cancer. [36][37][38] Chronically stressed or depressed individuals are also more likely to have poorer health habits, such as poor sleep patterns, poor nutrition, lack of exercise, and substance use, which also place them at greater risk for disease.…”