Transcriptomic profiling of trigeminal nucleus caudalis and spinal cord dorsal horn
BRAIN RESEARCH
Authors: Kogelman, Lisette J. A.; Elgaard-Christensen, Rikke; Olesen, Jes; Jansen-Olesen, Inger; Hansen, Thomas F.
Abstract
The pain sensation system is highly conserved among species, thus animal models have been used to investigate relevant tissues. The focus for head-specific pain has been on the primary nociceptive neurons in the trigeminal pathway, i.e. trigeminal ganglia. The secondary nociceptive neurons of the trigeminal pathway, trigeminal nucleus caudalis (TNC), have not been assessed. We expect different gene expression profiles compared to the homologous spinal cord dorsal horn (SDH), as several signalling substances provoke head-specific pain but not peripheral pain. We aim to provide expression profiles of TNC and SDH, tissues highly relevant for pain- and migraine-studies. We extracted RNA from laser capture micro-dissected laminae I-V from TNC and SDH from six Wistar rats for RNA-Sequencing. We showed the expression profiles of genes involved in neural signal transmission and found that among all G protein-coupled receptors Gabbr1 was highest expressed in both tissues. Among the migraine-associated genes we showed that Cacnala, where non-synonyms mutations can cause familial hemiplegic migraine, was highly expressed with a slightly lower expression in TNC than in SDH. To show the genetic differences between the two homologous systems we performed a differential expression analysis, revealing 1696 genes higher and 1895 genes lower expressed genes in TNC than in SDH, of which many were neuronal-related. The high number of differentially expressed genes shows the large genetic difference between the trigeminal and spinothalamic system. Our results contribute to the characterization of nociceptive pathways, which may help us understanding why several signalling molecules cause headache and no peripheral pain. (C) 2018 Elsevier B.V. All rights reserved.
mRNA and Protein Levels for GABA(A)alpha 4, alpha 5, beta 1 and GABA(B)R1 Receptors are Altered in Brains from Subjects with Autism
JOURNAL OF AUTISM AND DEVELOPMENTAL DISORDERS
Authors: Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rooney, Robert J.; Patel, Diven H.; Thuras, Paul D.
Abstract
We have shown altered expression of gamma-aminobutyric acid A (GABA(A)) and gamma-aminobutyric acid B (GABA(B)) receptors in the brains of subjects with autism. In the current study, we sought to verify our western blotting data for GABBR1 via qRT-PCR and to expand our previous work to measure mRNA and protein levels of 3 GABA(A) subunits previously associated with autism (GABR alpha 4; GABR alpha 5; GABR beta 1). Three GABA receptor subunits demonstrated mRNA and protein level concordance in superior frontal cortex (GABR alpha 4, GABR alpha 5, GABR beta 1) and one demonstrated concordance in cerebellum (GABI'R1). These results provide further evidence of impairment of GABAergic signaling in autism.