Pathogenesis of Cluster Headache: From Episodic to Chronic Form, the Role of Neurotransmitters and Neuromodulators

The profile of refractory chronic cluster headache

INTRODUCTION

Chronic cluster headache (CCH) is a relatively rare primary headache disorder whose management is often challenging. The prevalence of refractory CCH (rCCH) is unknown. Our aim is to describe the frequency of rCCH within a population of CCH, define the clinical profile of the refractory patients and the treatments they underwent.

METHODS

We conducted a cross-sectional study through a review of the medical records of CCH patients in six hospitals in Madrid, Spain. Data on epidemiological, clinical presentation, treatment and disease activity at the moment were collected. The European Headache Federation diagnostic criteria were used for rCCH definition. High disease activity was defined as having at least 3 severe attacks per week that impact quality of life despite treatment. Non-rCCH and rCCH groups were compared.

RESULTS

88 CCH patients were analyzed, 68.2% (60/88) met rCCH criteria at some point in their evolution. A longer diagnostic delay (4.6 ± 7.1 vs. 3.2 ± 3.7 years, p = 0.017) was observed in rCCH. All rCCH patients tried therapies without established evidence from randomized clinical trials. OnabotulinumtoxinA and galcanezumab were initiated in 77.3% (68/88) and 5.7% (5/88), but discontinued in 52.9% (36/68) and 60.0% (3/5), respectively. Occipital nerve stimulation (ONS) was implanted in 29.6% (26/88), with 50.0% (13/26) still active. Other treatment options are described and discussed. Despite treatment, 60.2% (53/88) still have high disease activity.

CONCLUSION

CCH is a disorder with poor prognosis, meeting refractoriness criteria in more than half. OnabotulinumtoxinA and ONS could be the effective in refractory patients.

Cluster Headache and Hypoxia: Breathing New Life into an Old Theory, with Novel Implications

Cluster headache is a severe, poorly understood disorder for which there are as yet virtually no rationally derived treatments. Here, Lee Kudrow's 1983 theory, that cluster headache is an overly zealous response to hypoxia, is updated according to current understandings of hypoxia detection, signaling, and sensitization. It is shown that the distinctive clinical characteristics of cluster headache (circadian timing of attacks and circannual patterning of bouts, autonomic symptoms, and agitation), risk factors (cigarette smoking; male gender), triggers (alcohol; nitroglycerin), genetic findings (GWAS studies), anatomical substrate (paraventricular nucleus of the hypothalamus, solitary tract nucleus/NTS, and trigeminal nucleus caudalis), neurochemical features (elevated levels of galectin-3, nitric oxide, tyramine, and tryptamine), and responsiveness to treatments (verapamil, lithium, melatonin, prednisone, oxygen, and histamine desensitization) can all be understood in terms of hypoxic signaling. Novel treatment directions are hypothesized, including repurposing pharmacological antagonists of hypoxic signaling molecules (HIF-2; P2X3) for cluster headache, breath training, physical exercise, high-dose thiamine, carnosine, and the flavonoid kaempferol. The limits of current knowledge are described, and a program of basic and translational research is proposed.

A retrospective cohort study: is COVID-19 BNT162b2 mRNA vaccination a trigger factor for cluster headache?

OBJECTıVE: Cluster headache (CH) is a coronavirus 2019 (COVID-19) vaccination-related adverse event. There are a few case reports of relapses or de novo cluster episodes following the vaccine. The disease's pathophysiology is still not clear. The most widely accepted mechanism is activation of the trigeminocervical complex (TCC). However, the correlation between vaccination and CH is unexplainable. Its goal is to compare the CH bouts of patients before and after the vaccine.

METHODS

Patients with a history of CH and who had never experienced COVID-19 illness during the pandemic were included in this retrospective cohort analysis. The semi-structured survey was administered face to face to 24 CH patients (16 male). The headache features before and after vaccination were detailed in this survey.

RESULTS

18 patients got vaccinated twice, and 6 of them had no vaccination. After the first vaccination, 83.3% of them had CH bout; after the second vaccination, 72.2% of them had CH bout. We divided headache episodes into three groups: (1) before vaccination, (2) after the first vaccination, and (3) after the second vaccination. The third group had a higher pain intensity (9.30 ± 0.630, p = 0.047) and remitting longer (20.00 ± 5.40 days, p = 0.019) than the other groups. The management of the 53.3% bouts after vaccinations was less effective than the usual episodes.

CONCLUSION

Most ECH patients experienced new bouts more intense and longer duration after vaccinations than their previous bouts, the mechanism, and pathogenesis of the bouts are the subject of future research. The new studies can be a light for understanding the CH pathophysiology more deeply.

Cluster headache: understandings of current knowledge and directions for whole process management

Cluster headache (CH) is a common primary headache that severely impacts patients' quality of life, characterized by recurrent, severe, unilateral headaches often centered around the eyes, temples, or forehead. Distinguishing CH from other headache disorders is challenging, and its pathogenesis remains unclear. Notably, patients with CH often experience high levels of depression and suicidal tendencies, necessitating increased clinical attention. This comprehensive assessment combines various reports and the latest scientific literature to evaluate the current state of CH research. It covers epidemiology, population characteristics, predisposing factors, and treatment strategies. Additionally, we provide strategic insights into the holistic management of CH, which involves continuous, individualized care throughout the prevention, treatment, and rehabilitation stages. Recent advances in the field have revealed new insights into the pathophysiology of CH. While these findings are still evolving, they offer a more detailed understanding of the neurobiological mechanisms underlying this disorder. This growing body of knowledge, alongside ongoing research efforts, promises to lead to the development of more targeted and effective treatments in the future.

Transition of cluster headache: Depicting side-changing attacks as a chronic trait in an interview-based follow-up study

BACKGROUND

Cluster headache presents in an episodic and chronic form, between which patients can convert during the course of disease. We aimed to quantify the rate of cluster headache patients changing phenotype within one and five years and investigate the earlier proposed association between chronification and having side-shifting attacks.

METHODS

In total, 430 cluster headache patients well-characterized according to current International Classification of Headache Disorders criteria, who were all participants in a prior transition-study, were re-interviewed in an observational, retrospective, cross-sectional follow-up study design at the Danish Headache Center.

RESULTS

The transition rate for the whole cohort was 6.5% within one year and 19.8% within five years. The risk of becoming chronic if episodic was 4.0% within one year and 12.3% within five years. For conversion from chronic to episodic, the corresponding risk was 11.1% and 25.0%, respectively. Alterations in attack-side were reported in 32% of all chronic patients, generating an odds ratio of 2.24 of being chronic as opposed to episodic if experiencing side-shifting attacks.

CONCLUSIONS

A higher transition rate since the original cross-sectional study demonstrates cluster headache as a non-static condition. Identifying a risk of transition within one and five years, based on current phenotype along with high odds of being chronic when experiencing a shift of attack-side, offers a valuable clinical compass in the dialogue with the patient.

Oxycodone-induced dopaminergic and respiratory effects are modulated by deep brain stimulation

Introduction: Opioids are the leading cause of overdose death in the United States, accounting for almost 70,000 deaths in 2020. Deep brain stimulation (DBS) is a promising new treatment for substance use disorders. Here, we hypothesized that VTA DBS would modulate both the dopaminergic and respiratory effect of oxycodone. Methods: Multiple-cyclic square wave voltammetry (M-CSWV) was used to investigate how deep brain stimulation (130 Hz, 0.2 ms, and 0.2 mA) of the rodent ventral segmental area (VTA), which contains abundant dopaminergic neurons, modulates the acute effects of oxycodone administration (2.5 mg/kg, i.v.) on nucleus accumbens core (NAcc) tonic extracellular dopamine levels and respiratory rate in urethane-anesthetized rats (1.5 g/kg, i.p.). Results: I.V. administration of oxycodone resulted in an increase in NAcc tonic dopamine levels (296.9 ± 37.0 nM) compared to baseline (150.7 ± 15.5 nM) and saline administration (152.0 ± 16.1 nM) (296.9 ± 37.0 vs. 150.7 ± 15.5 vs. 152.0 ± 16.1, respectively, p = 0.022, n = 5). This robust oxycodone-induced increase in NAcc dopamine concentration was associated with a sharp reduction in respiratory rate (111.7 ± 2.6 min-1 vs. 67.9 ± 8.3 min-1; pre- vs. post-oxycodone; p < 0.001). Continuous DBS targeted at the VTA (n = 5) reduced baseline dopamine levels, attenuated the oxycodone-induced increase in dopamine levels to (+39.0% vs. +95%), and respiratory depression (121.5 ± 6.7 min-1 vs. 105.2 ± 4.1 min-1; pre- vs. post-oxycodone; p = 0.072). Discussion: Here we demonstrated VTA DBS alleviates oxycodone-induced increases in NAcc dopamine levels and reverses respiratory suppression. These results support the possibility of using neuromodulation technology for treatment of drug addiction.

Neurologic Disorders in Women and Sleep

Sleep disorders in women remain underrecognized and underdiagnosed mainly because of gender bias in researching and characterizing sleep disorders in women. Symptoms of common sleep disorders are frequently missed in the general female population and are expected to be further overlooked because of overlapping symptoms in women with neurologic disorders. Given the bidirectional relationship with sleep and neurologic disorders, it remains critical to be aware of the presentation and impact of sleep disorders in this patient population. This article reviews available data on sleep disorders in women with neurologic disorders and discusses their distinctive features.

High frequency deep brain stimulation can mitigate the acute effects of cocaine administration on tonic dopamine levels in the rat nucleus accumbens

Cocaine's addictive properties stem from its capacity to increase tonic extracellular dopamine levels in the nucleus accumbens (NAc). The ventral tegmental area (VTA) is a principal source of NAc dopamine. To investigate how high frequency stimulation (HFS) of the rodent VTA or nucleus accumbens core (NAcc) modulates the acute effects of cocaine administration on NAcc tonic dopamine levels multiple-cyclic square wave voltammetry (M-CSWV) was used. VTA HFS alone decreased NAcc tonic dopamine levels by 42%. NAcc HFS alone resulted in an initial decrease in tonic dopamine levels followed by a return to baseline. VTA or NAcc HFS following cocaine administration prevented the cocaine-induced increase in NAcc tonic dopamine. The present results suggest a possible underlying mechanism of NAc deep brain stimulation (DBS) in the treatment of substance use disorders (SUDs) and the possibility of treating SUD by abolishing dopamine release elicited by cocaine and other drugs of abuse by DBS in VTA, although further studies with chronic addiction models are required to confirm that. Furthermore, we demonstrated the use of M-CSWV can reliably measure tonic dopamine levels in vivo with both drug administration and DBS with minimal artifacts.

Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating side effect of many common anti-cancer agents that can lead to dose reduction or treatment discontinuation, which decrease chemotherapy efficacy. Long-term CIPN can interfere with activities of daily living and diminish the quality of life. The mechanism of CIPN is not yet fully understood, and biomarkers are needed to identify patients at high risk and potential treatment targets. Metabolomics can capture the complex behavioral and pathophysiological processes involved in CIPN. This chapter is to review the CIPN metabolomics studies to find metabolic pathways potentially involved in CIPN. These potential CIPN metabolites are then investigated to determine whether there is evidence from studies of other neuropathy etiologies such as diabetic neuropathy and Leber hereditary optic neuropathy to support the importance of these pathways in peripheral neuropathy. Six potential biomarkers and their putative mechanisms in peripheral neuropathy were reviewed. Among these biomarkers, histidine and phenylalanine have clear roles in neurotransmission or neuroinflammation in peripheral neuropathy. Further research is needed to discover and validate CIPN metabolomics biomarkers in large clinical studies.

Dysregulation of Amino Acid, Lipid, and Acylpyruvate Metabolism in Idiopathic Intracranial Hypertension: A Non-targeted Case Control and Longitudinal Metabolomic Study

Background: Idiopathic intracranial hypertension (IIH) is characterized by increased intracranial pressure occurring predominantly in women with obesity. The pathogenesis is not understood. We have applied untargeted metabolomic analysis using ultrahigh-performance liquid chromatography-mass spectrometry to characterize the cerebrospinal fluid (CSF) and serum in IIH compared to control subjects. Methods and findings: Samples were collected from IIH patients (n = 66) with active disease at baseline and again at 12 months following therapeutic weight loss. Control samples were collected from gender- and weight-matched healthy controls (n = 20). We identified annotated metabolites in CSF, formylpyruvate and maleylpyruvate/fumarylpyruvate, which were present at lower concentrations in IIH compared to control subjects and returned to values observed in controls following weight loss. These metabolites showed the opposite trend in serum at baseline. Multiple amino acid metabolic pathways and lipid classes were perturbed in serum and CSF in IIH alone. Serum lipid metabolite pathways were significantly increased in IIH. Conclusions: We observed a number of differential metabolic pathways related to amino acid, lipid, and acylpyruvate metabolism, in IIH compared to controls. These pathways were associated with clinical measures and normalized with disease remission. Perturbation of these metabolic pathways provides initial understanding of disease dysregulation in IIH.

Proteomic and metabolomic profiling of acupuncture for migraine reveals a correlative link via energy metabolism

Migraine is a neurovascular disease with a high disability rate. Acupuncture treatment has emerged as a safe and viable alternative prophylactic therapy that can effectively alleviate the duration and frequency of migraine attacks. However, the therapeutic mechanisms underlying the effects of acupuncture are yet to be systematically elucidated. In this study, we enrolled female patients with migraine without aura (n = 20) and healthy controls (n = 10). Patients received acupuncture treatment on DU20, DU24, bilateral GB13, GB8, and GB20, applied three times per week over the course of 4 weeks for 12 sessions in total. Blood samples were collected from the median cubital vein before and after acupuncture treatment. Proteomic and metabolomic profiling was performed using liquid chromatography-mass spectrometry to determine the characteristics of differentially expressed molecules and expression of their corresponding biological pathways as well as to elucidate the pathogenesis of migraine and the biological effects underlying the treatment of migraine with acupuncture. Proteomic and metabolomic profiling of plasma samples from patients with migraine without aura before and after acupuncture treatment revealed enrichment of immune-related pathway functions and the arginine synthesis pathway. Joint pathway analyses revealed significant enrichment of the pentose phosphate and glycolysis/gluconeogenesis pathways in patients with migraine. The glycolysis/gluconeogenesis and riboflavin metabolism pathways were significantly enriched after acupuncture treatment. The expression levels of various key proteins and metabolites, including α-D-glucose, flavin adenine dinucleotide, biliverdin reductase B, and L-glutamate, were significantly differentially expressed before and after acupuncture treatment in patients with migraine without aura. Treatment of migraine with acupuncture was associated with significant changes in key molecules and pathways, indicative of physiological changes in the trigeminovascular system, glutamate neurotoxicity, and other migraine-related physiological changes. Overall, our comprehensive analysis using proteomic and metabolomic profiling demonstrates that energy metabolism may serve as a key correlative link in the occurrence of migraine and the therapeutic effects of acupuncture treatment. Our findings may facilitate the identification of diagnostic and therapeutic modalities in the ongoing search for effective treatments for migraine attacks.

Reveal the Antimigraine Mechanism of Chuanxiong Rhizoma and Cyperi Rhizoma Based on the Integrated Analysis of Metabolomics and Network Pharmacology

Migraine is a common neurological disorder that manifests as recurrent attacks of unilateral and throbbing headache. Conioselinum anthriscoides “Chuanxiong” (Apiaceae; Chuanxiong rhizoma) and Cyperus rotundus L. (Cyperaceae; Cyperi rhizoma) (CRCR), is a classic prescription for treating migraine. This study aimed to reveal the potential mechanisms of CRCR extract against migraine using integrated analysis of metabolomics and network pharmacology. Behavioral changes in the nitroglycerin rat migraine model were determined from von Frey withdrawal response. Untargeted serum metabolomics was used to identify the differentially expressed metabolites and metabolic pathways. The differentially expressed metabolites were analyzed to obtain the corresponding targets by a compound–reaction–enzyme–gene network. Network pharmacology was used to construct a compound–target–pathway network. The common targets of metabolomics and network pharmacology were further analyzed. Metabolomics analysis identified 96 differentially expressed metabolites and 77 corresponding targets. Network pharmacology analysis identified 201 potential targets for CRCR against migraine. By intersecting 77 targets with 201 targets, monoamine oxidase A (MAO-A), monoamine oxidase B (MAO-B), and catechol-O-methyltransferase (COMT) were identified as the common targets, and MAO-A, MAO-B, and COMT were involved in the tyrosine metabolism pathway. Further experiments demonstrated that the contents of MAO-A and COMT were significantly increased in serum and brainstem tissue of the migraine rats. CRCR extract significantly decreased the contents of MAO-A and COMT, while no significant difference was found in MAO-B. Metabolomics analysis indicated that the contents of 3,4-dihydroxyphenylacetate (DOPAC) and 3-(4-hydroxyphenyl)pyruvate (HPP) were significantly increased in the migraine rats, and CRCR extract caused significant decreases in DOPAC and HPP. Interestingly, DOPAC and HPP were two differentially expressed metabolites involved in the tyrosine metabolism pathway. Correlation analysis showed that DOPAC and HPP were highly positively correlated with MAO-A and COMT. Taken together, two key differentially expressed metabolites (DOPAC and HPP), two key targets (MAO-A and COMT), and one relevant metabolic pathway (tyrosine metabolism) showed great importance in the treatment of migraine. This research could provide a new understanding of the potential mechanism of CRCR against migraine. More attentions should be paid into the tyrosine metabolism pathway in future studies.

[Trigeminal autonomic cephalgias: features of diagnosis and treatment]

Trigeminal autonomic cephalgias is a group of primary headaches, including cluster headache, paroxysmal hemicrania and hemicrania continua, as well as two forms of short- lasting unilateral neuralgiform headache attacks, the complexity of diagnosis of which is determined by the low prevalence and some similarity of clinical manifestations both among themselves and with other diseases in particular with migraine and trigeminal neuralgia. Despite the rather short duration of headache attacks, the intensity of the pain syndrome reaches a severe and very severe degree, and the high frequency of paroxysms per day significantly complicates abortion treatment and leads to a pronounced professional and social maladjustment. At the same time, the possibility of using effective specific prophylactic therapy determines the importance of accurate diagnosis and, therefore, the knowledge of neurologists on this issue.

Study of arginine metabolism in medication overuse chronic migraine: possible defect in NO synthesis

BACKGROUND AND AIM

The pathogenesis of the pain that occurs in episodic migraine attack is due to the activation of the trigeminal system's first neuron receptors located on vessel wall. The release from the endothelium of nitric oxide, a product of arginine metabolism, causes vasodilation and stretching of the vascular trigeminal system and promotes pain. It is unknown whether this same metabolic event is involved in the pain accompanying chronic migraine. To understand the possible role of arginine in the pathogenesis of chronic migraine patients, we evaluated the metabolism of arginine in plasma of chronic migraine and control subjects.

METHODS

We evaluated the metabolism of arginine in a group of patients affected by chronic migraine. Quantification of arginine, ornithine, citrulline, monomethyl arginine (NMMA), dimethylarginines (ADMA, SDMA), and tyramine was performed by ultra-performance liquid chromatography coupled with a triple quadrupole mass spectrometer.

RESULTS

Chronic migraine patients showed low plasma levels of arginine, significantly elevated levels of ornithine, ADMA, and NMMA whereas the levels of citrulline and SDMA were in the range of controls.

CONCLUSIONS

The elevated levels of ADMA and NMMA, inhibitors of nitric oxide synthase, suggest that the metabolism of arginine may be inhibited with a possible reduction of NO release in the circulation of chronic patients. This suggests that the origin of pain may not be related to the vasodilation of trigeminal vascular system that occurs in episodic migraine patients.

Recently available and emerging therapeutic strategies for the acute and prophylactic management of cluster headache: a systematic review and expert opinion

Introduction: Although it causes a huge burden to sufferers, cluster headache (CH), remains an undertreated condition, partly due to the absence of established acute and prophylactic treatment options. New therapeutic approaches providing fast and safe relief from CH are needed. Areas covered: A systematic review was conducted, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendation on recently published (last 5 years) papers on CH treatment. The authors also collected preliminary results from ongoing trials on emerging therapeutic/preventive pharmacological and interventional approaches for CH. Studies and results are reviewed and discussed. Expert opinion: The complexity of CH pathophysiology prevents the definition of reliable acute and preventive treatments. In the real-world clinical setting, several treatments are combined to provide relief to patients and increase their quality of life. Drugs targeting neuropeptides or their receptors within the trigeminovascular network are of particular interest to prevent CH attacks. Calcitonin gene-related peptide (CGRP) blockade seems attractive and promising, but studies on anti-CGRP monoclonal antibodies indicated rather modest or even absence of a prophylactic effect. A deeper insight into CH pathophysiology, and combined approaches may lead the path to new, more effective, and personalized CH therapies.

Can the effects of the mitochondrial DNA mutations found in Leber’s hereditary optic neuropathy be protective against the development of cluster headache in smokers?

Is it possible that some mitochondrial DNA (mtDNA) mutations enhance the risk of developing a headache disorder while other mutations actually confer a protective effect? Mitochondrial disorders have been linked to migraine but very rarely to cluster headache (CH). The true pathogenesis of CH is unknown but a linkage to cigarette smoking is irrefutable. Leber’s hereditary optic neuropathy is a syndrome of bilateral vision loss that typically manifests in a patient’s 20s and 30s, is male predominant, and its sufferers are heavy smokers and heavy drinkers. Tobacco exposure is so linked to the condition that only smokers appear to develop vision loss while nonsmokers remain unaffected carriers of their mutations. In essence, the Leber’s hereditary optic neuropathy population is the CH population but at present there have been no reported cases of CH in this mitochondrial subgroup. Thus, could the effects of the mtDNA mutations found in Leber’s hereditary optic neuropathy, which involve complex I of the electron transport chain, actually confer a protective effect against the development of CH? This article will delve into this theory.