Cluster Headache Genomewide Association Study and Meta-Analysis Identifies Eight Loci and Implicates Smoking as Causal Risk Factor.

OBJECTIVE: The objective of this study was to aggregate data for the first genomewide association study meta-analysis of cluster headache, to identify genetic risk variants, and gain biological insights. METHODS: A total of 4,777 cases (3,348 men and 1,429 women) with clinically diagnosed cluster headache were recruited from 10 European and 1 East Asian cohorts. We first performed an inverse-variance genomewide association meta-analysis of 4,043 cases and 21,729 controls of European ancestry. In a secondary trans-ancestry meta-analysis, we included 734 cases and 9,846 controls of East Asian ancestry. Candidate causal genes were prioritized by 5 complementary methods: expression quantitative trait loci, transcriptome-wide association, fine-mapping of causal gene sets, genetically driven DNA methylation, and effects on protein structure. Gene set and tissue enrichment analyses, genetic correlation, genetic risk score analysis, and Mendelian randomization were part of the downstream analyses. RESULTS: The estimated single nucleotide polymorphism (SNP)-based heritability of cluster headache was 14.5%. We identified 9 independent signals in 7 genomewide significant loci in the primary meta-analysis, and one additional locus in the trans-ethnic meta-analysis. Five of the loci were previously known. The 20 genes prioritized as potentially causal for cluster headache showed enrichment to artery and brain tissue. Cluster headache was genetically correlated with cigarette smoking, risk-taking behavior, attention deficit hyperactivity disorder (ADHD), depression, and musculoskeletal pain. Mendelian randomization analysis indicated a causal effect of cigarette smoking intensity on cluster headache. Three of the identified loci were shared with migraine. INTERPRETATION: This first genomewide association study meta-analysis gives clues to the biological basis of cluster headache and indicates that smoking is a causal risk factor. ANN NEUROL 2023;94:713-726.

Easy tools to screen Italian women suffering from migraine with and without aura in early reproductive age.

OBJECTIVE: Early diagnosis of migraine with (MA)/without aura (MO) is vitally important to prevent adverse events during combined hormonal contraceptive (CHC) use and to provide personalized surveillance programs during pregnancy. The aim of this study is to provide clinicians with simple and fast tools to diagnose MO and MA in daily clinical practice. STUDY DESIGN: This study was based on a questionnaire to women of early reproductive age (18-35 years old) then randomized to undergo a neurological consultation. The ID-migraine questionnaire (PIN) and visual aura rating scale (VARS) were used. RESULTS: A total of 240 subjects were included in the study, with a total prevalence of MO diagnosed by PIN of 67.0% of subjects with headache, 49.2% of the total study population, and of MA by VARS of 12.5% subjects with headache, 9.2% of the total study population. Eighty-seven neurological examinations were randomly performed: PIN showed a sensitivity of 85.7% (95% CI 75.3%-92.9%) and a specificity of 52.9% (95% CI 27.8%-77.0%), while VARS displayed a sensitivity of 100.0% (95% CI 69.2%-100.0%) and a specificity of 45.5% (95% CI 16.8%-76.6%). CONCLUSION: High sensitivity, in particular for the presence of MA, associated with low specificity suggest that PIN and VARS questionnaires can be effective tools to identify those young patients who require specific neurological examinations in view of the prescription of a CHC or pregnancy planning.

Genetic variation in CHRNA7 and CHRFAM7A is associated with nicotine dependence and response to varenicline treatment.

The role of nicotinic acetylcholine receptors (nAChR) in nicotine dependence (ND) is well established; CHRNA7, encoding the α7 subunit, has a still uncertain role in ND, although it is implicated in a wide range of neuropsychiatric conditions. CHRFAM7A, a hybrid gene containing a partial duplication of CHRNA7, is possibly involved in modulating α7 nAChR function. The aim of this study was to investigate the role of CHRNA7 and CHRFAM7A genetic variants in ND and to test the hypothesis that α7 nAChR variation may modulate the efficacy of varenicline treatment in smoking cessation. We assessed CHRNA7 and CHRFAM7A copy number, CHRFAM7A exon 6 ∆2 bp polymorphism, and sequence variants in the CHRNA7 proximal promoter in an Italian sample of 408 treatment-seeking smokers. We conducted case-control and quantitative association analyses using two smoking measures (cigarettes per day, CPD, and Fagerström Test for Nicotine Dependence, FTND). Next, driven by the hypothesis that varenicline may exert some of its therapeutic effects through activation of α7 nAChRs, we restricted the analysis to a subgroup of 142 smokers who received varenicline treatment. The CHRNA7 promoter variant rs28531779 showed association with both smoking quantitative measures (FNTD p = 0.026, ß = 0.89, 95% CI 0.11-1.67; CPD p = 0.006, ß = 4.82 95% CI 1.42-8.22). Moreover, in the varenicline-treated subgroup we observed association of CHRFAM7A copy number with 6 months smoking abstinence (p = 0.035, OR = 3.18, 95% CI = 1.09-9.30). Thus, our study points to a possible role of genetic variation in CHRNA7 and CHRFAM7A in tobacco addiction mechanisms and response to varenicline treatment.

Pharmacokinetics and tolerability of oral cannabis preparations in patients with medication overuse headache (MOH)-a pilot study.

PURPOSE: The recent release of a medical cannabis strain has given a new impulse for the study of cannabis in Italy. The National Health Service advises to consume medical cannabis by vaporizing, in decoction or oil form. This is the first study that explores the pharmacokinetics and tolerability of a single oral dose of cannabis as decoction (200 ml) or in olive oil (1 ml), as a first step to improve the prescriptive recommendations. METHODS: This is a single-center, open-label, two-period crossover study designed to assess the pharmacokinetics and tolerability of oral cannabis administered to 13 patients with medication overuse headache (MOH). A liquid chromatography tandem-mass spectrometry (LC-MS/MS) method was conducted for the quantification of THC, CBD, 11-OH-THC, THC-COOH, THC-COOH-glucuronide, THCA-A, and CBDA. Blood pressure, heart rate, and a short list of symptoms by numerical rating scale (NRS) were assessed. RESULTS: Decoctions of cannabis showed high variability in cannabinoids content, compared to cannabis oil. For both preparations, THCA-A and CBDA were the most widely absorbed cannabinoids, while THC and CBD were less absorbed. The most important differences concern the bioavailability of THC, higher in oil (AUC0-24 7.44, 95% CI 5.19, 9.68) than in decoction (AUC0-24 3.34, 95% CI 2.07, 4.60), and the bioavailability of CBDA. No serious adverse events were reported. CONCLUSIONS: Cannabis decoction and cannabis oil showed different pharmacokinetic properties, as well as distinct consequences on patients. This study was performed in a limited number of patients; future studies should be performed to investigate the clinical efficacy in larger populations.

A genome-wide analysis in cluster headache points to neprilysin and PACAP receptor gene variants.

BACKGROUND: Cluster Headache (CH) is a severe primary headache, with a poorly understood pathophysiology. Complex genetic factors are likely to play a role in CH etiology; however, no confirmed gene associations have been identified. The aim of this study is to identify genetic variants influencing risk to CH and to explore the potential pathogenic mechanisms. METHODS: We have performed a genome-wide association study (GWAS) in a clinically well-defined cohort of 99 Italian patients with CH and in a control sample of 360 age-matched sigarette smoking healthy individuals, using the Infinium PsychArray (Illumina), which combines common highly-informative genome-wide tag SNPs and exonic SNPs. Genotype data were used to carry out a genome-wide single marker case-control association analysis using common SNPs, and a gene-based association analysis focussing on rare protein altering variants in 745 candidate genes with a putative role in CH. RESULTS: Although no single variant showed statistically significant association at the genome-wide threshold, we identified an interesting suggestive association (P = 9.1 × 10-6) with a common variant of the PACAP receptor gene (ADCYAP1R1). Furthermore, gene-based analysis provided significant evidence of association (P = 2.5 × 10-5) for a rare potentially damaging missense variant in the MME gene, encoding for the membrane metallo-endopeptidase neprilysin. CONCLUSIONS: Our study represents the first genome-wide association study of common SNPs and rare exonic variants influencing risk for CH. The most interesting results implicate ADCYAP1R1 and MME gene variants in CH susceptibility and point to a role for genes involved in pain processing. These findings provide new insights into the pathogenesis of CH that need further investigation and replication in larger CH samples.

NDP-α-MSH attenuates heart and liver responses to myocardial reperfusion via the vagus nerve and JAK/ERK/STAT signaling.

Melanocortin peptides afford cardioprotection during myocardial ischemia/reperfusion via janus kinases (JAK), extracellular signal-regulated kinases (ERK) and signal transducers/activators of transcription (STAT) pathways. Here we investigated whether melanocortin-induced modulation of the JAK/ERK/STAT signaling occurs via the cholinergic anti-inflammatory pathway, focusing our study on cardiac and hepatic responses to prolonged myocardial ischemia/reperfusion. Ischemia was produced in rats by ligature of the left anterior descending coronary artery for 30min; effects of ischemia/reperfusion were evaluated using Western blot of heart and liver proteins. Intravenous treatment, during coronary artery occlusion, with the melanocortin analog (Nle(4), D-Phe(7))α-melanocyte-stimulating hormone (NDP-α-MSH) induced a left ventricle up-regulation of the cardioprotective transcription factors pJAK2, pERK1/2 and pTyr-STAT3 (JAK-dependent), and a reduction in the levels of the inflammatory mediators tumor necrosis factor-α (TNF-α) and pJNK (a transcription factor also involved in apoptosis), as assessed at the end of the 2-h reperfusion period. Further, these beneficial effects of NDP-α-MSH were associated with heart over-expression of the pro-survival proteins heme oxygenase-1 (HO-1) and Bcl-XL, and decrease of ventricular arrhythmias and infarct size. In the liver NDP-α-MSH induced a decrease in the pJAK2 and pTyr-STAT3 levels, and strongly reduced pERK1/2 expression. In the liver of ischemic rats NDP-α-MSH also blunted pJNK activity and TNF-α expression, and up-regulated Bcl-XL. Bilateral cervical vagotomy prevented all effects of NDP-α-MSH, both in the heart and liver. These results indicate that melanocortins inhibit heart and liver damage triggered by prolonged myocardial ischemia/reperfusion likely, as main mechanism, via the vagus nerve-mediated modulation of the JAK/STAT/ERK signaling pathways.

Impact of continuing or quitting smoking on episodic cluster headache: a pilot survey.

BACKGROUND: The majority of patients suffering from cluster headache (CH) are smokers and it has been suggested that smoking may trigger the development of CH. The aim of this pilot survey was to describe: 1. the differences between current, former, and never smokers CH patients; 2. if smoking changed during an active cluster period; 3. if CH changed after quitting. METHODS: All outpatients with episodic CH according to the criteria of ICHD-II who were consecutively seen for the first time from October 2010 to April 2012 at a headache centre were interviewed by phone using a specifically prepared questionnaire. Statistical differences between continuous variables were analysed by the Student's t-test or the one-way analysis of variance (ANOVA), followed by Newman-Keuls post-hoc testing. Comparisons between percentages were made using the Chi-square test or Fisher's exact test. All data were expressed as the mean ± standard deviation (SD). RESULTS: Among a total of 200 patients surveyed (172 males, 28 females; mean age ± SD: 48.41 ± 12 years) there were 60%, 21%, and 19% of current, former, and never smokers, respectively. Current smokers reported longer active periods (12.38 ± 10 weeks) and a higher maximum number of attacks per day (3.38 ± 1) compared to never smoker CH patients (5.68 ± 4 weeks, P <0.05 and 2.47 ± 1, P <0.05, respectively). During the active period most of the patients stated to decrease (45.7%) or not to change (45.7%) the number of cigarettes smoked. Among those who decreased smoking, most (83.8%) reported that they had less desire to smoke. After quitting, the majority of former smokers stated that their headache had not changed. CONCLUSIONS: Patients with episodic CH who are also smokers appear to have a more severe form of the disorder. However, it is unlikely that between CH and smoking there is a causal relationship, as CH patients rarely improve quitting smoking.

A case of a GH-producing pituitary adenoma associated with a unilateral headache with autonomic signs.

A 66-year-old man suffered from a drug-resistant, left-sided headache with autonomic signs, triggered by the supine position. The acromegalic facies initially suggested a possible increase in basal plasma levels of GH, but routine haematological controls excluded abnormal values of GH. Cerebral and facial CT scan and MRI did not detect any alterations in the nasal sinuses, except for a mucous cyst. Surgical ablation of the cyst did not alleviate the pain. Further endocrinological the pain. Further endocrinological tests demonstrated an increase of IGF-1 (somatomedin C), and another MRI scan of the sellar region confirmed the presence of a pituitary macroadenoma on the left paramedian side. After an initial improvement of the symptomatology due to trans-sphenoidal ablation of a benign GH-producing macroadenoma, the headache worsened again. Pain was well correlated with the increased plasma levels of IGF-1. The patient died suddenly for myocardial infarct.

Adrenocorticotropin reverses hemorrhagic shock in anesthetized rats through the rapid activation of a vagal anti-inflammatory pathway.

OBJECTIVE: Several melanocortin peptides have a prompt and sustained resuscitating effect in conditions of hemorrhagic shock. The transcription nuclear factor kappaB (NF-kappaB) triggers a potentially lethal systemic inflammatory response, with marked production of tumor necrosis factor-alpha (TNF-alpha), in hemorrhagic shock. Here we investigated whether the hemorrhagic shock reversal produced by the melanocortin ACTH-(1-24) (adrenocorticotropin) depends on the activation of the recently recognized, vagus nerve-mediated, brain "cholinergic anti-inflammatory pathway". METHODS AND RESULTS: Anesthetized rats were stepwise bled until mean arterial pressure (MAP) stabilized at 20-25 mm Hg. The severe hypovolemia was incompatible with survival, and all saline-treated animals died within 30 min. In rats intravenously (i.v.) treated with ACTH-(1-24), neural efferent activity along vagus nerve (monitored by means of a standard system for extracellular recordings) was markedly increased, and the restoration of cardiovascular and respiratory functions was associated with blunted NF-kappaB activity and with decreased TNF-alpha mRNA liver content and TNF-alpha plasma levels. Bilateral cervical vagotomy, pretreatment with the melanocortin MC(4) receptor antagonist HS014, atropine sulfate or chlorisondamine, but not with atropine methylbromide, prevented the life-saving effect of ACTH-(1-24) and the associated effects on NF-kappaB activity and TNF-alpha levels. HS014 and atropine sulfate prevented, too, the ACTH-(1-24)-induced increase in neural efferent vagal activity, and accelerated the evolution of shock in saline-treated rats. CONCLUSIONS: The present data show, for the first time, that the melanocortin ACTH-(1-24) suppresses the NF-kappaB-dependent systemic inflammatory response triggered by hemorrhage, and reverses shock condition, by brain activation (in real-time) of the "cholinergic anti-inflammatory pathway", this pathway seeming to be melanocortin-dependent.

Efferent vagal fibre stimulation blunts nuclear factor-kappaB activation and protects against hypovolemic hemorrhagic shock.

BACKGROUND: We investigated whether electrical stimulation (STIM) of efferent vagus nerves may suppress nuclear factor (NF)-kappaB activation and the inflammatory cascade in hemorrhagic (Hem) shock. METHODS AND RESULTS: Rats were subjected to bilateral cervical vagotomy (VGX) or sham surgical procedures. Hem shock was induced by intermittent withdrawing of blood until mean arterial pressure stabilized within the range of 35 to 40 mm Hg. Application of constant voltage pulses to the caudal vagus ends (STIM; 5 V, 2 ms, 1 Hz for 12 minutes, 5 minutes after mean arterial pressure stabilization) increased survival time (VGX+Hem+Sham STIM=38+/-3 minutes; VGX+Hem+STIM >180 minutes), reverted the marked hypotension (VGX+Hem+Sham STIM=33+/-3 mm Hg; VGX+Hem+STIM=66+/-5 mm Hg), inhibited IkappaBalpha liver loss, and blunted the augmented NF-kappaB activity, decreased hepatic tumor necrosis factor (TNF)-alpha mRNA (VGX+Hem+Sham STIM=1.42+/-0.5 amount of TNF-alpha m-RNA; VGX+Hem+STIM=0.51+/-0.2 amount of TNF-alpha mRNA), and reduced plasma TNF-alpha (VGX+Hem+Sham STIM=190+/-24 pg/mL; VGX+Hem+STIM=87+/-15 pg/mL). Chlorisondamine, a nicotinic receptor antagonist, abated the effects of vagal stimulation. CONCLUSIONS: Our results show a parasympathetic inhibition of NF-kappaB by which the brain opposes NF-kappaB activation in the liver and modulates the inflammatory response during acute hypovolemic hemorrhagic shock.