This study identifies a GPCR, S1PR2, as a receptor for the Nogo-A-Δ20 domain of the membrane protein Nogo-A, which inhibits neuronal growth and synaptic plasticity.

We have generated a transgenic rat model using RNAi and used it to study the role of the membrane protein Nogo-A in synaptic plasticity and cognition. The membrane protein Nogo-A is expressed in CNS oligodendrocytes and subpopulations of neurons, and it is known to suppress neurite growth and regeneration. The constitutively expressed polymerase II-driven transgene was composed of a micro-RNA-targeting Nogo-A placed into an intron preceding the coding sequence for EGFP, thus quantitatively labeling cells according to intracellular microRNA expression. The transgenic microRNA in vivo efficiently reduced the concentration of Nogo-A mRNA and protein preferentially in neurons. The resulting significant increase in longterm potentiation in both hippocampus and motor cortex indicates a repressor function of Nogo-A in synaptic plasticity. The transgenic rats exhibited prominent schizophrenia-like behavioral phenotypes, such as perseveration, disrupted prepulse inhibition, and strong withdrawal from social interactions. This fast and efficient micro-RNA-mediated knockdown provides a way to silence gene expression in vivo in transgenic rats and shows a role of Nogo-A in regulating higher cognitive brain functions.animal model | Rtn4 | learning | memory G ene knockout (KO) technology has spurred the analysis of gene functions in mice during the past two decades (1) and has recently been expanded to other species using new genome modification technologies (2). Although germ-line gene ablation is a very powerful tool for investigating gene function in vivo, its most important drawback is that the complete loss of gene function often leads to molecular compensation, obscuring the role of the deleted gene. Tissue-or cell-specific KOs are more specific but are currently confined to mice as a model system. RNA interference (RNAi) is a viable alternative to the KO approach and represents a fast and powerful tool for manipulating gene expression (3). RNAi technology not only allows keeping the endogenous genomic locus intact, but it also enables the knockdown of multiple genes at the same time or the selective depletion of a specific isoform of mRNA transcripts (4). Another advantage is offered by the possibility of creating hypomorphic alleles instead of complete KOs, which can avoid embryonic lethality and better mirrors many human diseases and therapeutic interventions.Elucidating gene functions in transgenic rats has several important advantages over using mice (5). Their larger size simplifies interventions, such as microsurgery and multiple site in vivo electrophysiological recordings (6). Furthermore, higher-order cognitive functions are more developed in this social rodent species than in the more solitarily living mice (7,8). Hence, many behavioral tests are more advanced or validated for the rat species, especially regarding the behavioral assessment of complex neuropsychiatric disease phenotypes, such as negative symptoms in schizophrenia.For the rat, only polymerase (Pol) III-controlled shRNA RNAi models have been cre...

Background The fully human monoclonal antibody erenumab, which targets the calcitonin gene-related peptide (CGRP) receptor, was licensed in Switzerland in July 2018 for the prophylactic treatment of migraine. To complement findings from the pivotal program, this observational study was designed to collect and evaluate clinical data on the impact of erenumab on several endpoints, such as quality of life, migraine-related impairment and treatment satisfaction in a real-world setting. Methods An interim analysis was conducted after all patients completed 6 months of erenumab treatment. Patients kept a headache diary and completed questionnaires at follow up visits. The overall study duration comprises 24 months. Results In total, 172 adults with chronic or episodic migraine from 19 different sites across Switzerland were enrolled to receive erenumab every 4 weeks. At baseline, patients had 16.6 ± 7.2 monthly migraine days (MMD) and 11.6 ± 7.0 acute migraine-specific medication days per month. After 6 months, erenumab treatment reduced Headache Impact Test (HIT-6™) scores by 7.7 ± 8.4 (p < 0.001), the modified Migraine Disability Assessment (mMIDAS) by 14.1 ± 17.8 (p < 0.001), MMD by 7.6 ± 7.0 (p < 0.001) and acute migraine-specific medication days per month by 6.6 ± 5.4 (p < 0.001). Erenumab also reduced the impact of migraine on social and family life, as evidenced by a reduction of Impact of Migraine on Partners and Adolescent Children (IMPAC) scores by 6.1 ± 6.7 (p < 0.001). Patients reported a mean effectiveness of 67.1, convenience of 82.4 and global satisfaction of 72.4 in the Treatment Satisfaction Questionnaire for Medication (TSQM-9). In total, 99 adverse events (AE) and 12 serious adverse events (SAE) were observed in 62 and 11 patients, respectively. All SAE were regarded as not related to the study medication. Conclusions Overall quality of life improved and treatment satisfaction was rated high with erenumab treatment in real-world clinical practice. In addition, the reported impact of migraine on spouses and children of patients was reduced. Trial registration BASEC ID 2018–02,375 in the Register of All Projects in Switzerland (RAPS). Graphical Abstract

Functional recovery from central neurotrauma, such as spinal cord injury, is limited by myelin-associated inhibitory proteins. The most prominent example, Nogo-A, imposes an inhibitory cue for nerve fibre growth via two independent domains: Nogo-A-Δ20 (residues 544–725 of the rat Nogo-A sequence) and Nogo-66 (residues 1026–1091). Inhibitory signalling from these domains causes a collapse of the neuronal growth cone via individual receptor complexes, centred around sphingosine 1-phosphate receptor 2 (S1PR2) for Nogo-A-Δ20 and Nogo receptor 1 (NgR1) for Nogo-66. Whereas the helical conformation of Nogo-66 has been studied extensively, only little structural information is available for the Nogo-A-Δ20 region. We used nuclear magnetic resonance (NMR) spectroscopy to assess potential residual structural propensities of the intrinsically disordered Nogo-A-Δ20. Using triple resonance experiments, we were able to assign 94% of the non-proline backbone residues. While secondary structure analysis and relaxation measurements highlighted the intrinsically disordered character of Nogo-A-Δ20, three stretches comprising residues 561EAIQESL567, 639EAMNVALKALGT650, and 693SNYSEIAK700 form transient α-helical structures. Interestingly, 561EAIQESL567 is situated directly adjacent to one of the most conserved regions of Nogo-A-Δ20 that contains a binding motif for β1-integrin. Likewise, 639EAMNVALKALGT650 partially overlaps with the epitope recognized by 11C7, a Nogo-A-neutralizing antibody that promotes functional recovery from spinal cord injury. Diffusion measurements by pulse-field gradient NMR spectroscopy suggest concentration- and oxidation state-dependent dimerisation of Nogo-A-Δ20. Surprisingly, NMR and isothermal titration calorimetry (ITC) data could not validate previously shown binding of extracellular loops of S1PR2 to Nogo-A-Δ20.

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Introduction: There is limited real-world evidence on the burden of migraine among patients with prior preventive treatment failure (PPTF). In the BECOME Swiss subanalysis, we aimed to assess current prevalence of PPTF in patients with migraine seen at specialised headache centres in Switzerland and burden of migraine in these patients. Furthermore, we assessed this burden in subgroups stratified by monthly migraine days (MMDs) and number of PPTFs. Methods: BECOME was a prospective, multicentre, non-interventional two-part study conducted in 17 countries across Europe and Israel. This subanalysis includes patients visiting ten headache specialist centres in Switzerland. In part 1, patients visiting the centres over 3 months were screened by physicians for frequency of PPTF, MMD and other migraine

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