Histamine in Migraine and Brain

Abstract

Background.-Histamine has been studied in both health and disease since the initial description a century ago. With its vasodilative effect, it was suggested early on to be involved in the pathophysiology of migraine. Over the past 25 years, much has been learned about histamine as a neurotransmitter in the central nervous system. The role of this neurotransmitter system in migraine has not been previously reviewed.Objective.-Discuss a potential role of the brain histaminergic system in migraine.Methods.-Unstructured literature search with a no specific hypothesis-driven approach.Results.-There is substantial evidence that systemically given histamine may elicit, maintain, and aggravate headache. The mechanisms for this are not known, and histamines do not penetrate the blood-brain barrier (BBB). However, circulating histamine may influence hypothalamic activity via the circumventricular organs that lack BBB. In the rat, prolonged activation of meningeal nociceptors induced by dural mast cell degranulation has been observed. Subcutaneous injections of N-alpha-methyl histamine, a catabolite of histamine with high affinity to the histamine H3 receptor, probably have some migraine preventive effect.A negative feedback on histamine release from mast cells in proximity to C-fiber endings has been a postulated mechanism.Most antihistamines have shown to be ineffective as acute medication for migraine. Two centrally acting potent H1 receptor antagonists (cinnarizine and cyproheptadine) have been reported to be efficacious in preventing migraine. However, the proof for this is limited, and their efficacy has been ascribed other actions than the antihistaminergic. In general, lack of specificity and side effects limit the potential use of centrally acting H1 and H2 antagonists.Brain histamine is synthesized by neurons that are restricted to the posterior basal hypothalamus, more specific to the tuberomamillary nucleus (TMN), and that project practically to the whole central nervous system. The posterior hypothalamus is a suspected locus in quo in several primary headaches. Recently, a positron emission tomography study performed in the prodromal phase of migraine attacks supported the idea of initial involvement of this area. In another recent study, the thalamic nuclei receiving trigeminal output was also shown to have direct connections with the ventral TMN. The central histaminergic system plays an important role in the complex sleep-wake cycle, promoting cortical excitability during wakening and attention, and it consolidates the wake state. The period of the day, in the evenings and during the night, when there is reduced susceptibility for migraine attacks corresponds with less central histaminergic firing. Activation of both the H3 and the H4 receptor promotes inhibitory actions on neurons. The H3 receptor causes autoinhibition of the histaminergic neurons themselves, and centrally acting H3 receptor agonist prodrugs have shown to both inhibit neurogenic inflammation in dura, to induce sleep, and to produce antino...

Diamine Oxidase rs10156191 and rs2052129 Variants Are Associated With the Risk for Migraine

“…In contrast with these findings, a Spanish group claimed, in nonscientific newspapers, that 90% of patients with migraine show DAO deficiency, which could be improved with the ingestion of a DAO capsule before the meals, leading to migraine improvement (http://www.lavanguardia.com/salud/20130306/54369041093/cientificos-demuestran-que-una-enzima-sirve-para-prevenir-el-90-de-migranas.html) Histamine acts through four metabotropic histamine receptors, which are all G‐protein‐coupled (GPCR) (HRH1, HRH2, HRH3, and HRH4) transducer extracellular signals via Gq, Gs, and Gi/o proteins, respectively. In general, histamine modulates inflammatory and allergic responses via HRH1, gastric acid secretion through HRH2, neurotransmitter release in the central nervous system (CNS) via HRH3, and chemotaxis and inflammatory mediators release via HRH4 . The brain stores and releases histamine from mast cells and histaminergic neurons of the tuberomammillary nucleus of the posterior basal hypothalamus.…”

Memory and multitasking performance during acute allergic inflammation in seasonal allergic rhinitis

“…The underlying mechanisms of allergy-related effects on learning and memory are still unclear. Although the underlying mechanisms are still elusive, it has been proposed that peripheral histamine may impact central histaminergic neurotransmission and hypothalamic activity via the circumventricular organs that lack a blood-brain barrier or via activation of negative feedback mechanisms of central histamine release [39]. For example, cytokines have been found to act on brain functions by passing the blood-brain barrier or via vagal nerve stimulation [27,28].…”

The relationship between sleep and headache in children: Implications for treatment

“…However, both H3R and H4R ligands may theoretically have migraine prophylactic properties. Despite being promising drug targets for several diseases, the lack of specificity and undesired side effects will probably be a major problem (81).…”