Neuropeptides: modulators of immune responses in health and disease

Adverse childhood experiences are associated with migraine and vascular biomarkers

OBJECTIVES

Migraine is a risk factor for stroke in young women. Biomarker studies implicate endothelial activation as a possible mechanism. Emerging relationships of childhood adversity with migraine, and with inflammation, a component of endothelial activation, suggest that it may play a role in the migraine-stroke association. Our objective is to evaluate the relationship between adverse childhood experiences (ACEs), migraine, and vascular biomarker levels in premenopausal women.

METHODS

Vascular and metabolic biomarkers from women 18-50 years, including 125 with migraine (interictal) and 50 without migraine, were evaluated. An ACE questionnaire was later collected by mail (response rate 80.6%, 100 migraineurs, 41 controls).

RESULTS

Migraineurs and controls were demographically similar. Migraineurs reported adversity more commonly than controls (71% vs 46%, odds ratio [OR] = 1.53, 95% confidence interval 1.07-2.17). Average ACE scores were elevated in migraineurs as compared with controls (2.4 vs 0.76, P < .001). ACE scores correlated with headache frequency (0.37, P = .001) and younger age of headache onset (-0.22, P = .04). It also correlated with body mass index (r = 0.43, P = .0001), von Willebrand factor activity (r = 0.21, P = .009), tissue plasminogen activator antigen (r = 0.28, P = .004), prothrombin activation fragment (r = 0.36, P = .001), high-sensitivity C-reactive protein (r = 0.98, P = .0001), transforming growth factor-beta1 (r = 0.28, P = .003), tissue necrosis factor-alpha (r = 0.20, P = .03), interleukin-6 (r = 0.22, P = .03), adiponectin (r = -0.29, P = .003), and nitrate/nitrite concentration (r = -314, P = .001). Logistic regression analyses (adjusted for vascular risk factors and migraine) demonstrated an association of childhood adversity with inflammatory factors (high-sensitivity C-reactive protein, interleukin-6, and tissue necrosis factor-alpha).

CONCLUSIONS

In young women, adverse childhood events are associated with migraine, particularly chronic and transformed migraine, and with vascular biomarkers, especially inflammatory biomarkers. These findings implicate early life stress as a link between migraine and endothelial activation.

Endomorphins in rheumatoid arthritis, osteoarthritis, and experimental arthritis

The opioid tetrapeptides endomorphins (EM)-1 and EM-2 are widely expressed in central nervous system and immune tissues of rats and humans. Their analgesic properties are well characterized but they also have anti-inflammatory properties. EM-1 significantly attenuated the onset of hindpaw inflammation in adjuvant-induced arthritis in rats. Immunohistochemical staining demonstrated the presence of EMs in T cells, macrophages, and fibroblasts in synovial tissues from patients with osteo- or rheumatoid arthritis (RA). In an ex vivo superfusion system, EM-1 potently inhibited the release of proinflammatory cytokines interleukin (IL)-6 and IL-8 from synovial tissues from patients with osteo- or RA. These results demonstrate that EMs are endogenously synthesized within human immune cells and have the potential to act as potent therapeutic agents in the treatment of chronic inflammatory disease. We discuss the clinical potential for EM analogues chemically modified to resist proteolytic degradation and identify modified protease-resistant analogues with enhanced bioactivity.

Physiology of psychoneuroimmunology: a personal view

This article offers a personal view on how the concept of the existence of a network of immune-neuro-endocrine interactions has evolved in the last 30 years. The main topic addressed is the relevance of the exchange of signals between the immune, endocrine and nervous systems for immunoregulation and brain functions. Particular emphasis is given to circuits involving immune cell products, the hypothalamus-pituitary-adrenal axis and the sympathetic nervous system. The operation of these circuits can affect immune functions and the course of inflammatory, autoimmune and infectious diseases. We also discuss increasing evidence that brain-born cytokines play an important role in brain physiology and in the integration of the immune-neuro-endocrine network.

Effects of stress on inflammatory autoimmune disease: destructive or protective?

We have summarised evidence in the literature for modulatory effects of stress on inflammatory autoimmune disease. We find that overall there is strong evidence for such an interrelationship. Apparent discrepancies between groups and studies are probably due to differences in experimental design, whether longitudinal or retrospective. Other important variables are the specific effects of different types of stress and the intensity and timing of the stressor relative to onset of inflammation. We conclude that there is much of benefit to be learned from scientific study of stress, such as harnessing and rationalising of stressful experiences through self-expression in patients, or the identification of novel anti-inflammatory compounds activated by stress.