RNA expression profiling in brains of familial hemiplegic migraine type 1 knock-in mice

Abstract

Background: Various CACNA1A missense mutations cause familial hemiplegic migraine type 1 (FHM1), a rare monogenic subtype of migraine with aura. FHM1 mutation R192Q is associated with pure hemiplegic migraine, whereas the S218L mutation causes hemiplegic migraine, cerebellar ataxia, seizures, and mild head trauma-induced brain edema. Transgenic knock-in (KI) migraine mouse models were generated that carried either the FHM1 R192Q or the S218L mutation and were shown to exhibit increased Ca V 2.1 channel activity. Here we investigated their cerebellar and caudal cortical transcriptome. Methods: Caudal cortical and cerebellar RNA expression profiles from mutant and wild-type mice were studied using microarrays. Respective brain regions were selected based on their relevance to migraine aura and ataxia. Relevant expression changes were further investigated at RNA and protein level by quantitative polymerase chain reaction (qPCR) and/or immunohistochemistry, respectively. Results: Expression differences in the cerebellum were most pronounced in S218L mice. Particularly, tyrosine hydroxylase, a marker of delayed cerebellar maturation, appeared strongly upregulated in S218L cerebella. In contrast, only minimal expression differences were observed in the caudal cortex of either mutant mice strain. Conclusion: Despite pronounced consequences of migraine gene mutations at the neurobiological level, changes in cortical RNA expression in FHM1 migraine mice compared to wild-type are modest. In contrast, pronounced RNA expression changes are seen in the cerebellum of S218L mice and may explain their cerebellar ataxia phenotype.

Cortical Spreading Depression Causes Unique Dysregulation of Inflammatory Pathways in a Transgenic Mouse Model of Migraine

“…This is in line with our previous study that identified only minor differences in cortical gene expression between FHM1 mice and WT under naïve conditions [20]. Also, the CSD effect was relatively small, which shows that the brain is relatively resistant with respect to changing the expression of genes even after a major perturbation such as multiple CSD events.…”

“…In that respect, it is noteworthy that naïve trigeminal ganglia of FHM1 R192Q migraine mice exhibit a pro-inflammatory phenotype with a higher number of activated macrophages, activated microglia and increased cytokine expression levels [42–45]. In the caudal cortex, in which CSD events originate, only nine genes are differently expressed in naïve FHM1 mutant mice [20]. Of those genes, Camkk1, Gpr34, Tom1l2 and Cort are linked to inflammation, thus providing some evidence that a pro-inflammatory state may also exist in the naïve FHM1 R192Q cortex.…”

“…For the factors genotype and CSD, as well as for the interaction factor, genes with nominal p values ≤0.005 were used for downstream analysis. In an earlier gene expression study in which we compared naïve cortical gene expression levels from FHM1 mice with WT mice, we found an overrepresentation of differentially expressed genes from chromosome 8 resulting from remaining 129/Ola-derived genetic background that was present as a consequence of the gene targeting procedure [20]. Therefore, we removed all genes from chromosome 8 from the genotype effect gene list.…”

Gene co-expression analysis identifies brain regions and cell types involved in migraine pathophysiology: a GWAS-based study using the Allen Human Brain Atlas

“…For migraine, no gene expression data from disease-conditions are available. Few gene expression profiling studies have been carried out for migraine, i.e., in whole blood of episodic and chronic migraine patients (Hershey et al 2004 ) and menstrual migraine patients (Hershey et al 2012 ), in immortalised cell lines of migraine with aura patients (Nagata et al 2009 ), and in brain material of transgenic KI FHM1 mice (de Vries et al 2014 ), but no overlapping deregulated genes or pathways have been identified. Nor is there a large set of causal genes, except for three genes ( CACNA1A, ATP1A2 and SCN1A ) (De Fusco et al 2003 ; Dichgans et al 2005 ; Ophoff et al 1996 ) that have been identified for FHM, that can guide gene identification efforts in the common forms of migraine.…”

Dual roles for an intracellular calcium-signaling pathway in regulating synaptic homeostasis and neuronal excitability

“…However, while this particular PLC can affect lipid signaling it would not trigger IP 3 release. More to the point of this thesis, an RNA expression dataset from R192Q and S218L knock-in mice tentatively identified PLCβ as an upregulated gene in the cerebellum from S218L preparations(DE VRIES et al 2014). Subsequent studies have not followed up on this lead.…”