Sulev Koks

Background: Wolfram syndrome (WFS1-Spectrum Disorder) is an ultra-rare monogenic form of progressive neurodegeneration and diabetes mellitus. In common with most rare diseases, there are no therapies to slow or stop disease progression. Sodium valproate, an anticonvulsant with neuroprotective properties, is anticipated to mediate its effect via alteration of cell cycle kinetics, increases in p21cip1 expression levels and reduction in apoptosis and increase in Wolframin protein expression. To date, there have been no multicentre randomised controlled trials investigating the efficacy of treatments for neurodegeneration in patients with Wolfram syndrome. Methods: TREATWOLFRAM is an international, multicentre, double-blind, placebo-controlled, randomised clinical trial designed to investigate whether 36-month treatment with up to 40 mg/kg/day of sodium valproate will slow the rate of loss of visual acuity as a biomarker for neurodegeneration in patients with Wolfram syndrome. Patients who satisfied the eligibility criteria were randomly assigned (2:1) to receive two times per day oral gastro-resistant sodium valproate tablets up to a maximum dose of 800 mg 12 hourly or sodium valproate-matched placebo. Using hierarchical repeated measures analyses with a 5% significance level, 80% power and accounting for an estimated 15% missing data rate, a sample size of 70 was set. The primary outcome measure, visual acuity, will be centrally reviewed and analysed on an intention-to-treat population. Background: The protocol was approved by the National Research Ethics Service (West of Scotland; 18/WS/0020) and by the Medicines and Healthcare products Regulatory Agency. Recruitment into TREATWOLFRAM started in January 2019 and ended in November 2021. The treatment follow-up of TREATWOLFRAM participants is ongoing and due to finish in November 2024. Updates on trial progress are disseminated via Wolfram Syndrome UK quarterly newsletters and at family conferences for patient support groups. The findings of this trial will be disseminated through peer-reviewed publications and international presentations. Background: NCT03717909.

An individual's genetics contributes to their risk of developing amyotrophic lateral sclerosis (ALS); however, there is still a large proportion of the heritability of ALS to be understood. Part of this missing heritability may lie in complex variants, such as the long interspersed element 1 (L1) retrotransposon, which have yet to be evaluated. The majority of L1 insertions in the human genome are no longer able to retrotranspose, but to date 279 retrotransposition-competent (RC) L1s have been reported. Many RC-L1s are polymorphic for their presence/absence; therefore, each individual will have a different number and complement of RC-L1s. These elements have been hypothesized to be involved in disease processes by multiple mechanisms such as somatic mutation by retrotransposition, the triggering of neuroinflammation and DNA damage. We hypothesize that L1s may influence disease development either through their effects on endogenous genes or through the properties that enable them to retrotranspose. Whole genome sequencing data from the New York Genome Center ALS consortium were used to characterize L1 variation identifying 2,803 polymorphic L1 elements and association analysis was performed in European individuals (ALS/ALS with other neurological disorder (ALSND) n = 2,653, controls n = 320). There were no individual L1 elements associated with disease, but we did identify a significant increase in the number of RC-L1s in ALS/ALSND genomes (p = 0.01) and the presence of ≥46 RC-L1s showed the most significant association (OR = 1.09 (1.02-1.16), p = 0.01) with disease. Analysis of individual L1s and their association with age at onset and survival identified one L1 whose presence was significantly associated with a lower age at onset (52.7 years) compared to homozygous absent individuals (59.2 years) (padj = 0.009). Our study has identified novel genetic factors for both disease risk and age at onset in ALS providing further evidence for the role of L1 retrotransposons in neurodegenerative diseases.

Background: The long noncoding RNA, NEAT1, is recognized as a key regulator of proinflammatory gene expression; Yet, its functional role in migraine remains unexplored, despite the central role of neuroinflammatory mechanisms in migraine pathophysiology. This study examines the implication of NEAT1 in the trigeminal ganglion activation, which underlies photophobia associated with migraine. Methods: Light aversion behavior was induced by intranasal injection of the TRPA1 activator, umbellulone. Male mouse behavior was assessed by the total time the mouse stays in the light between the dark and light compartments. To gain insight to the NEAT1-mediated photophobia mechanism, gene expression of candidate genes and non-coding RNAs interactions were assessed using RNA-sequencing, qPCR analysis, histology and dual-luciferase reporter gene assay. Results: NEAT1 was upregulated in the trigeminal ganglion of male photophobia mice; Downregulation of NEAT1 by intravenous injection of shNEAT1 adeno-associated virus vectors attenuated NEAT1 expression and alleviated photophobia-like behavior in mice. The elevated NEAT1 expression in the trigeminal ganglion of photophobia mice corresponds to the downregulation of miR-196a-5p and upregulation Trpm3 RNA level. Predicted analysis suggested NEAT1/miR-196a-5p ceRNA network exists in photophobia mice. Indeed, knocking down NEAT1 upregulated miR-196a-5p, whilst downregulated Trpm3 gene expression level, in the trigeminal ganglion of photophobia mice. Further investigation using dual-luciferase reporter gene assay identified NEAT1 interacting with miR-196a-5p, whilst miR-196a-5p interacting with Trpm3. Similar to knocking down NEAT1, TRPM3 inhibition reduced photophobia-like behavior. Conclusions: We conclude that NEAT1 is critical for promoting photophobia behavior via miR-196a-5p/Trpm3 coupling.

The fatal neurodegenerative disease, amyotrophic lateral sclerosis (ALS), leads to the degeneration of motor neurons in the brain and spinal cord. Many different genetic variants are known to increase the risk of developing ALS, however much of the disease heritability is still to be identified. To identify novel genetic factors, we characterised SINE-VNTR-Alu (SVA) presence/absence variation in 4403 genomes from the New York Genome Center (NYGC) ALS consortium. SVAs are a type of retrotransposon able to mobilise in the human genome generating new insertions that can modulate gene expression and mRNA splicing and to date 33 insertions are known to cause a range of genetic diseases. In the NYGC ALS consortium sequence data 2831 non-reference genome SVAs were identified and 95% of these insertions were rare with an insertion allele frequency of less than 0.01. Association analysis of the common SVAs with ALS risk, age at onset and survival did not identify any SVAs that survived correction for multiple testing. However, there were three different rare SVA insertions in the ALS associated gene NEK1 identified in four different individuals with ALS. The frequency of these rare insertions in NEK1 was significantly higher in the individuals with ALS from the NYGC ALS consortium compared to the gnomAD SV non-neuro controls (p = 0.0002). This study was the first to characterise non-reference SVA presence/absence variation in a large cohort of ALS individuals identifying insertions as potential candidates involved in disease development for further investigation.

Background: Evidence indicates phenotypic and biological overlap between psychiatric and neurodegenerative disorders. Further identification of underlying mutual and unique biological mechanisms may yield novel multi-disorder and disorder-specific therapeutic targets. The metabolome represents an important domain for target identification as metabolites play critical roles in modulating a diverse range of biological processes. Methods: We used Mendelian randomisation (MR) to test the causal effects of ~ 1000 plasma metabolites and ~ 300 metabolite ratios on anxiety, bipolar disorder, depression, schizophrenia, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease and multiple sclerosis. Follow-up analyses were conducted using statistical colocalisation, multivariable Bayesian model averaging MR (MR-BMA) and polygenic risk score analysis in the UK Biobank. Results: MR analyses identified 85 causal effects involving 77 unique metabolites passing FDR correction and robust sensitivity analyses (IVW-MR OR range 0.73-1.48; pFDR < 0.05). No evidence of reverse causality was identified. Multivariable MR-BMA analyses implicated sphingolipid metabolism in psychiatric disorder risk and carnitine derivatives in risk for amyotrophic lateral sclerosis and multiple sclerosis. Although polygenic risk scores for prioritised metabolites showed limited prediction in the UK Biobank, those nominally significant were directionally consistent with MR estimates. Downstream colocalisation in regions containing influential variants identified greater than suggestive evidence (PP.H4 ≥ 0.6) for a shared causal variant for 29 metabolite/psychiatric disorder trait-pairs on chromosome 11 at the FADS gene cluster. Most of these metabolites were lipids containing linoleic or arachidonic acid. Additional colocalisation was identified between the ratio of histidine-to-glutamine, glutamine, Alzheimer's disease and SPRYD4 gene expression on chromosome 12. Conclusions: Although no single metabolite had a causal effect on both a psychiatric and a neurodegenerative disease, results suggest a broad effect of lipids across brain disorders, with a particular role for lipids containing linoleic or arachidonic acid in psychiatric disorders. The metabolites identified here may help inform future targeted interventions.