Search for Correlations Between Genotypes and Electrophysiological Patterns in Migraine: The MTHFR C677T Polymorphism and Visual Evoked Potentials

Cephalalgia ◽  
2007 ◽  
Vol 27 (10) ◽  
pp. 1142-1149 ◽  
Author(s):  
D Magis ◽  
M Allena ◽  
G Coppola ◽  
L Di Clemente ◽  
P Gérard ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Methylenetetrahydrofolate Reductase ◽  
Mthfr C677t ◽  
Pattern Reversal ◽  
C677t Polymorphism ◽  
Mthfr C677t Polymorphism ◽  
Grand Average ◽  
The Brain ◽  
Visual Evoked

Interictally, migraineurs have on average a reduction in habituation of pattern-reversal visual evoked potentials (PR-VEP) and in mitochondrial energy reserve. 5,10-Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and its C677T polymorphism may be more prevalent in migraine. The aim of this study was to search in migraineurs for a correlation between the MTHFR C677T polymorphism and the PR-VEP profile. PR-VEP were recorded in 52 genotyped migraine patients: 40 female, 24 without (MoA), 28 with aura (MA). Among them 21 had a normal genotype (CC), 18 were heterozygous (CT) and 13 homozygous (TT) for the MTHFR C677T polymorphism. Mean PR-VEP N1-P1 amplitude was significantly lower in CT compared with CC, and tended to be lower in TT with increasing age. The habituation deficit was significantly greater in CC compared with TT subjects. The correlation between the cortical preactivation level, as reflected by the VEP amplitude in the first block of averages, and habituation was stronger in CC than in CT or TT. The MTHFR C677T polymorphism could thus have an ambiguous role in migraine. On one hand, the better VEP habituation which is associated with its homozygosity, and possibly mediated by homocysteine derivatives increasing serotoninergic transmission, may protect the brain against overstimulation. On the other hand, MTHFR C677T homozygosity is linked to a reduction of grand average VEP amplitude with illness duration, which has been attributed to brain damage.

scholarly journals Effect of riboflavin supplementation on blood pressure and possible effect modification by the MTHFR C677T polymorphism: a randomised trial in rural Gambia

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 1034
Author(s):  
Modou Jobe ◽  
Mary Ward ◽  
Bakary Sonko ◽  
Abdul Khalie Muhammad ◽  
Ebrima Danso ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Large Scale ◽  
Methylenetetrahydrofolate Reductase ◽  
Controlled Trial ◽  
Randomised Trial ◽  
Mthfr C677t ◽  
C677t Polymorphism ◽  
Phenotypic Effect ◽  
Riboflavin Deficiency ◽  
Mthfr C677t Polymorphism

Introduction: Emerging evidence links a functional polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene (rs1801133) with hypertension in adults. This variant reduces the affinity of MTHFR for its cofactor flavin-adenine dinucleotide (FAD) which is derived from riboflavin. Previous work has demonstrated a blood pressure (BP)-lowering effect of riboflavin in Irish adults with the MTHFR 677TT variant. We hypothesize that the almost-universal severe riboflavin deficiency seen in rural Gambia mimics the BP phenotypic effect of the TT variant and exacerbate the effect of the CT variant. We will test this in a randomised, placebo-controlled trial, whether intervention with riboflavin can decrease BP in adults in rural Gambia. Methods: This is a phase 2 recall-by-genotype randomised single-blind placebo-controlled riboflavin supplementation trial. We will use the Keneba biobank to recruit approximately 102 individuals aged between 18-70, previously genotyped for the MTHFR C677T polymorphism and identified as carrying the T allele; these individuals will be age- and sex-matched to a similar number of homozygotes for the C allele. The participants will be randomised to a 16-week supplementation trial of 5 mg/day riboflavin or placebo, supplied every 14 days. The primary outcome, BP, will be measured at baseline and at weeks 8 and 16. Blood samples, collected at baseline and week 16, will be analysed for riboflavin, homocysteine, red cell folate, cobalamin (vitamin B12) and pyridoxine (vitamin B6). Discussion: The study will evaluate the role of riboflavin supplementation in BP control within a population with high levels of riboflavin deficiency and will test a possible gene-nutrient interaction with the MTHFR C677T polymorphism. If improvements in BP are observed in this study, and proven in subsequent large-scale interventions, riboflavin could offer a cost-effective, safe and accessible option for the  prevention and control of hypertension in this population. Trial registration: ClinicalTrials.gov Identifier NCT03151096. Registered on 12 May 2017.

scholarly journals Exploring the dynamic mechanisms of steady-state visual evoked potentials at the whole-brain level: evidence from a computational study

2021 ◽  
Author(s):  
Ge Zhang ◽  
Yan Cui ◽  
Yangsong Zhang ◽  
Hefei Cao ◽  
Guanyu Zhou ◽  
...  
Keyword(s):  
Steady State ◽  
Evoked Potentials ◽  
Visual Evoked Potentials ◽  
Large Scale ◽  
Whole Brain ◽  
Frequency Sensitivity ◽  
Dynamic Mechanisms ◽  
Brain Level ◽  
The Brain ◽  
Visual Evoked

AbstractPeriodic visual stimulation can induce stable steady-state visual evoked potentials (SSVEPs) distributed in multiple brain regions and has potential applications in both neural engineering and cognitive neuroscience. However, the underlying dynamic mechanisms of SSVEPs at the whole-brain level are still not completely understood. Here, we addressed this issue by simulating the rich dynamics of SSVEPs with a large-scale brain model designed with constraints of neuroimaging data acquired from the human brain. By eliciting activity of the occipital areas using an external periodic stimulus, our model was capable of replicating both the spatial distributions and response features of SSVEPs that were observed in experiments. In particular, we confirmed that alpha-band (8-12 Hz) stimulation could evoke stronger SSVEP responses; this frequency sensitivity was due to nonlinear resonance and could be modulated by endogenous factors in the brain. Interestingly, the stimulus-evoked brain networks also exhibited significant superiority in topological properties near this frequency-sensitivity range, and stronger SSVEP responses were demonstrated to be supported by more efficient functional connectivity at the neural activity level. These findings not only provide insights into the mechanistic understanding of SSVEPs at the whole-brain level but also indicate a bright future for large-scale brain modeling in characterizing the complicated dynamics and functions of the brain.

scholarly journals MTHFR Gene Polymorphism and Age of Onset of Schizophrenia and Bipolar Disorder

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Mohamed A. El-Hadidy ◽  
Hanaa M. Abdeen ◽  
Sherin M. Abd El-Aziz ◽  
Mohammad Al-Harrass
Keyword(s):  
Bipolar Disorder ◽  
Healthy Subjects ◽  
Methylenetetrahydrofolate Reductase ◽  
Age Of Onset ◽  
Age At Onset ◽  
Mthfr C677t ◽  
Control Group ◽  
C677t Polymorphism ◽  
Mthfr C677t Polymorphism ◽  
Mthfr Gene Polymorphism

Objective. Several studies with contradictory results from different cultures about association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in schizophrenia and bipolar disorders. Little is known about this association in Arab culture and Egypt. So the present study aimed to assess the association of MTHFR C677T polymorphism in bipolar disorder (BD) and schizophrenia in comparison to control group. The association between MTHFR C677T polymorphism and the age at onset in schizophrenia or BD was also studied.Methods. Polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used to examine the genotype and allele frequencies of MTHFR C677T polymorphism in 149 healthy subjects and 134 bipolar and 103 schizophrenia patients.Results. In BD and schizophrenia, there was a higher prevalence of MTHFR C677T polymorphism than healthy subjects. Earlier age at onset was found in patients with BD, carrying one copy of the T allele or CT genotypes but not in patients with schizophrenia.Conclusion. The present findings suggest that the MTHFR C677T polymorphisms are likely to be associated with the risk of developing BD and schizophrenia and influence the age at onset of BD but not the age at onset of schizophrenia.

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