title: Identifying a gene expression signature of cluster headache in blood.
abstract: Cluster headache is a relatively rare headache disorder, typically characterized by multiple daily, short-lasting attacks of excruciating, unilateral (peri-)orbital or temporal pain associated with autonomic symptoms and restlessness. To better understand the pathophysiology of cluster headache, we used RNA sequencing to identify differentially expressed genes and pathways in whole blood of patients with episodic (n = 19) or chronic (n = 20) cluster headache in comparison with headache-free controls (n = 20). Gene expression data were analysed by gene and by module of co-expressed genes with particular attention to previously implicated disease pathways including hypocretin dysregulation. Only moderate gene expression differences were identified and no associations were found with previously reported pathogenic mechanisms. At the level of functional gene sets, associations were observed for genes involved in several brain-related mechanisms such as GABA receptor function and voltage-gated channels. In addition, genes and modules of co-expressed genes showed a role for intracellular signalling cascades, mitochondria and inflammation. Although larger study samples may be required to identify the full range of involved pathways, these results indicate a role for mitochondria, intracellular signalling and inflammation in cluster headache.
authors.affiliation: Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Else
authors.initials: E
authors.lastname: Eising
authors.affiliation: Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Nadine
authors.initials: N
authors.lastname: Pelzer
authors.affiliation: Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Lisanne S
authors.initials: LS
authors.lastname: Vijfhuizen
authors.affiliation: Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Boukje de
authors.initials: B
authors.lastname: Vries
authors.affiliation: Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Michel D
authors.initials: MD
authors.lastname: Ferrari
authors.affiliation: Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Peter A C
authors.initials: PA
authors.lastname: 't Hoen
authors.affiliation: Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Gisela M
authors.initials: GM
authors.lastname: Terwindt
authors.affiliation: Department of Human Genetics, Leiden University Medical Centre, Leiden, The Netherlands.|Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: Arn M J M
authors.initials: AM
authors.lastname: van den Maagdenberg
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D003027:Cluster Headache / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007249:Inflammation; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000378:metabolism; D017423:Sequence Analysis, RNA; D015398:Signal Transduction
chemical_list: D015415:Biomarkers