Validity of Serum Zinc/Copper Ratio as a Potential Novel Biomarker in Childhood Epilepsy.

BACKGROUND: Alterations in zinc and copper homeostasis may contribute to seizure susceptibility, development, termination, and response to antiepileptic medications. The current study examined the profile of zinc, copper, and their ratio in childhood epilepsy and its pharmacological variants (pharmacoresistant and pharmacoresponsive). METHODS: The study included 100 epileptic children (50 pharmacoresistant and 50 pharmacoresponsive) and 50 healthy, age- and gender-matched controls. History, clinical examination, and assays of serum zinc and copper were performed. Zinc/copper ratio was calculated. RESULTS: Serum zinc and the zinc/copper ratio were significantly lower in epileptic children than in controls (p < 0.001). Significantly lower zinc and zinc/copper ratio and higher copper levels were found in children treated with levetiracetam/sodium valproate/oxcarbazepine than those treated with levetiracetam alone or combined with sodium valproate (p < 0.05 for all). Epileptic children, particularly pharmacoresistant, exhibited significant negative correlations between the serum levels of zinc and copper (r = -0.279, p = 0.005, and r = -0.363 and p = 0.010, respectively). At cutoff value of zinc/copper ratio < 1.118 in diagnosing children with epilepsy, it gives a sensitivity of 64% and a specificity of 85% with the AUC = 0.8092. At cutoff value of zinc/copper ratio ≤ 0.7826 in distinguishing pharmacoresistant epilepsy, it produced 52% sensitivity, 64% specificity with AUC = 0.576 Conclusions: Low zinc and high copper levels were associated with childhood epilepsy especially those with pharmacoresistant type and treated with Oxcarbazepine. Zinc/copper ratio might be a potential biomarker in diagnosing childhood epilepsy and to some extent in predicting pharmacoresistant type.

Pharmacogenetic study of phosphatase and tensin homolog polymorphism (rs701848) in childhood epilepsy: relation to circulating Wnt signaling.

OBJECTIVE: The present study aimed at evaluating the potential contribution of Phosphatase and Tensin Homolog (PTEN) and its gene polymorphism (PTEN rs701848 T/C) in relation to Wingless/integrase-1 (Wnt) signaling in childhood epilepsy and the impact of antiepileptic medications on their serum levels. METHODS: This study included 100 children with epilepsy (50 pharmacoresistant and 50 pharmacoresponsive) and 50 matched controls. All subjects had their genotypes for the PTEN rs701848T/C polymorphism assessed using TaqManTM assays and real-time PCR. By using the sandwich ELISA technique, the blood concentrations of PTEN and Wnt3a were measured. RESULTS: Serum Wnt3a levels in epileptic patients were significantly higher than in the control group, p < 0.001. Children with epilepsy who received oxcarbazepine had considerably lower serum Wnt3a levels than those who didn't, p < 0.001.With an AUC of 0.71, the cutoff value for diagnosing epilepsy as serum Wnt3a > 6.2 ng/mL has a sensitivity of 55% and a specificity of 80%. When compared to controls, epileptic children had considerably more (TT) genotype and less (TC and CC) genotypes, p < 0.05 for all. Epileptic children had significantly higher (T) allele frequency than controls, p = 0.006 with OR (95%CI) = 1.962(1.206-3.192). Pharmacoresistant epileptic children had significantly higher (TT) genotype compared to pharmacoresponsive type (p = 0.020). CONCLUSION: We originally found a strong association between PTEN rs701848 T/C and childhood epilepsy, in particular pharmacoresistant type. Serum Wnt3a levels increased in epilepsy, but were not significantly different between different alleles of PTEN. In pharmaco-responsive children Wnt3a levels differed significantly between the different PTEN genotypes. Antiepileptics may affect Wnt3a levels.