Genetic Polymorphisms in Enzymes Involved in One-Carbon Metabolism and Anti-epileptic Drug Monotherapy on Homocysteine Metabolism in Patients With Epilepsy

Associations between one-carbon metabolism and valproic acid-induced liver dysfunction in epileptic patients

Valproic acid (VPA) has been widely used as an antiepileptic drug for decades. Although VPA is effective and well-tolerated, long-term VPA treatment is usually associated with hepatotoxicity. However, the underlying mechanisms of VPA-caused hepatotoxicity remain unclear. In this study, a total of 157 pediatric patients with epilepsy were recruited and divided into normal liver function (NLF, 112 subjects) group and abnormal liver function (ABLF, 45 subjects) group. We observed that MTHFR A1298C and MTHFR C677T variants may be linked to VPA-induced liver dysfunction (p = 0.001; p = 0.023, respectively). We also found that the MTHFR A1298C polymorphism was associated with a higher serum Hcy level (p = 0.001) and a lower FA level (p = 0.001). Moreover, the serum Hcy levels was strongly correlated with the GSH and TBARS concentrations (r = -0.6065, P < 0.001; r = 0.6564, P < 0.001, respectively). Furthermore, logistic analysis indicated that MTHFR A1298C/C677T polymorphisms and increased Hcy concentrations may be risk factors for VPA-induced liver dysfunction. These results suggested that individual susceptibility to VPA-induced liver dysfunction may result from MTHFR A1298C/C677T polymorphisms and increased Hcy levels. This study may be helpful for the prevention and guidance of VPA-induced liver dysfunction.

PERCHING syndrome caused by variant gene KLHL7 in the first Iranian patient: a case report study

Introduction and importance

PERCHING syndrome is a condition that affects many parts of the body and is caused by genes passed down from both parents. People with this syndrome have delays in their development, unusual facial features, trouble eating and breathing, slow overall growth, weak muscles, and stiff joints.

Case presentation

The child at the age of 6 months suffered from developmental delay, delayed walking, speech delay, and hypotonia and was referred to the Neurologist. Also, he has an abnormal phenotype. Whole-exome sequencing (WES) revealed a missense variant in the KLHL7 gene at a highly conserved genomic Chr7: 23124718T>G; NM_018846:exon3:c.110T>G:p.Val37Gly.

Clinical discussion

One way to explain the difference in physical characteristics caused by recessive KLHL7 mutations might be related to the person's genetic makeup. However, the genes someone has do not always accurately determine their physical traits.

Conclusion

This report will help us learn more about the different traits and characteristics of Perching syndrome. The authors need to do more research on how proteins work and study more about patients with different characteristics to fully understand this.

Valproic Acid in Pregnancy Revisited: Neurobehavioral, Biochemical and Molecular Changes Affecting the Embryo and Fetus in Humans and in Animals: A Narrative Review

Valproic acid (VPA) is a very effective anticonvulsant and mood stabilizer with relatively few side effects. Being an epigenetic modulator, it undergoes clinical trials for the treatment of advanced prostatic and breast cancer. However, in pregnancy, it seems to be the most teratogenic antiepileptic drug. Among the proven effects are congenital malformations in about 10%. The more common congenital malformations are neural tube defects, cardiac anomalies, urogenital malformations including hypospadias, skeletal malformations and orofacial clefts. These effects are dose related; daily doses below 600 mg have a limited teratogenic potential. VPA, when added to other anti-seizure medications, increases the malformations rate. It induces malformations even when taken for indications other than epilepsy, adding to the data that epilepsy is not responsible for the teratogenic effects. VPA increases the rate of neurodevelopmental problems causing reduced cognitive abilities and language impairment. It also increases the prevalence of specific neurodevelopmental syndromes like autism (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). High doses of folic acid administered prior to and during pregnancy might alleviate some of the teratogenic effect of VPA and other AEDs. Several teratogenic mechanisms are proposed for VPA, but the most important mechanisms seem to be its effects on the metabolism of folate, SAMe and histones, thus affecting DNA methylation. VPA crosses the human placenta and was found at higher concentrations in fetal blood. Its concentrations in milk are low, therefore nursing is permitted. Animal studies generally recapitulate human data.

Susceptibility to preoperative seizures in glioma patients with elevated homocysteine levels

OBJECTIVE

Seizures are a common clinical presentation in patients with glioma and substantially impact patients' quality of life. Hyperhomocysteinemia is defined as abnormally high serum levels of homocysteine (Hcy) and is reportedly linked to susceptibility to various nervous system diseases. However, it remains unclear whether and how hyperhomocysteinemia and its associated genetic polymorphisms promote seizures in glioma patients.

METHODS

We retrospectively reviewed all medical data from 127 patients with malignant gliomas, who underwent initial tumor resection by our team between July 2019 and June 2021 and had preoperative measurements of serum Hcy levels. According to whether they had at least one seizure before surgery, they were divided into the seizure and nonseizure groups. We also detected polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and measured intratumoral Hcy levels in these patients.

RESULTS

Hyperhomocysteinemia was a susceptibility factor for preoperative seizures in glioma patients according to both univariate analyses (P < 0.001) and multivariate logistic regression analyses (OR 1.239, 95% CI 1.062-1.445, P = 0.007). Patients with the MTHFR C677T variant exhibited elevated serum Hcy levels (P = 0.027) and an increased prevalence of preoperative seizures (P = 0.019). Intratumoral Hcy levels were positively correlated with serum Hcy levels (R = 0.231, P = 0.046) and were elevated in patients with hyperhomocysteinemia (P = 0.031), the MTHFR C677T variant (P = 0.002) and preoperative seizures (P = 0.003). High intratumoral Hcy levels, rather than hyperhomocysteinemia or the MTHFR C677T variant, emerged as an independent risk factor for preoperative seizures (OR 1.303, 95% CI 1.015-1.673, P = 0.038). Furthermore, the effects of hyperhomocysteinemia on epileptic susceptibility were reduced to nonsignificance when intratumoral Hcy was controlled to the same level between groups.

SIGNIFICANCE

Glioma patients with hyperhomocysteinemia and the MTHFR C677T variant were susceptible to preoperative seizures, suggesting their potential as biomarkers for the management of seizures in glioma patients. The elevation of intratumoral Hcy is a possible mechanism underlying this susceptibility.

Influence of Different Antiepileptic Drugs on Blood Ammonia and Homocysteine Levels in Children with Epilepsy

In this study, we performed a study on 106 children with epilepsy who were treated with sodium valproate (the VPA group, n = 37), oxcarbazepine (the OXC group, n = 34), or levetiracetam (the LEV group, n = 35). In addition, the clinical data of epileptic children who were newly diagnosed in the same period without antiepileptic drug (AED) treatment (the untreated group, n = 35) and normal children who received physical examination in our hospital (the healthy group, n = 35) were selected as controls. We analyzed the efficacy and safety of different AEDs, used blood ammonia and homocysteine levels as the observation indicators, and calculated the incidence of hyperammonemia (VAH) and hyperhomocysteinemia (HHcy) treated with different AEDs. And, based on the effect of epilepsy status on the cognitive function of patients, we also analyzed the effect of different AED treatments on children's cognitive function. Our results show that sodium valproate, oxcarbazepine, and levetiracetam are all effective in the treatment of children with epilepsy and can be used as the first-line choice of antiepileptic treatment for children with epilepsy. However, compared with sodium valproate, levetiracetam and oxcarbazepine have a lower incidence of adverse drug reactions and do not cause an increase in blood ammonia and Hcy levels, so they have higher safety of drug treatment. In addition, compared with sodium valproate, levetiracetam and oxcarbazepine have better recovery of cognitive function in children with epilepsy and so they have better application value.

Is There a Relation between 677C>T Polymorphism in the MTHFR Gene and the Susceptibility to Epilepsy in Young Patients? A Meta-Analysis

Background: Numerous data show a role for genetic polymorphisms in the development of epilepsy. Previously, the TT genotype of the MTHFR 677C>T polymorphism was found to be associated with a decreased leucocyte DNA methylation status. Polymorphisms in the MTHFR gene could modify the pharmacodynamics of many drugs. This meta-analysis aimed to assess the relationship between MTHFR 677C>T polymorphism and susceptibility to epilepsy in young patients. Methods: Available databases (PubMed, Embase, Google Scholar, SciELO, and Medline) were searched using specific keywords. Eight studies, published between 1999 and 2019, with 1678 young patients with epilepsy and 1784 controls, met the inclusion criteria. Apart from the total groups, additional analyses in age subgroups (i.e., young adults and children) were conducted. Statistical analyses were conducted using the RevMan 5.4 and MedCalc software. The pooled odds ratio (OR) was estimated with a random- or fixed-effects model depending on the heterogeneity. Analyses were performed for five genetic models, i.e., dominant (CT + TT vs. CC), recessive (TT vs. CC + CT), additive (TT vs. CC), heterozygous (CT vs. CC), and allelic (T vs. C). The publication bias was assessed with the use of Egger's and Begg's tests. Results: Both the MTHFR TT genotype (in the additive model) and the T allele (in the allelic model) significantly increased the risk of epilepsy when the total groups were compared (OR = 1.44, p = 0.002, and OR = 1.183, p = 0.001, respectively). The sensitivity analysis for these models indicated the stability of the results. Similarly, significant results were obtained among young adults for all the genetic models (dominant model: OR = 1.28, p = 0.002; recessive model: OR = 1.48, p = 0.003; additive model: OR = 1.63, p < 0.001; heterozygous model: OR = 1.21, p = 0.028; and allelic model: OR = 1.256, p < 0.001). Those results were also stable and reliable. In the group of children, no relation between 677C>T polymorphism and epilepsy was observed; however, the analysis was based only on three studies, and one study also comprised young adults. No publication bias was demonstrated. Conclusions: The meta-analysis revealed that the carrier state for the T allele as well as the TT genotype of the MTHFR 677C>T polymorphism increases the risk of epilepsy in young adults but not in children.