**10. The effects of surgery on oxygen stress in AED-resistant temporal lobe epilepsy**

López et al. (2007) studied the activity of anti-oxidant enzymes (SOD, catalase and GSH-Px) and markers of oxygen stress induced molecular neuronal injury (MDA and ROS) before and at various times after epileptic focus resection in 9 therapy resistant patients; a control group consisted of 32 healthy individuals. All the studied variables normalized postoperatively except SOD activity.

Several earlier interesting observations seem to be related to these findings to a certain extent. Turkdogan et al. (2002) found that increased lipid peroxidation in plasma may be causally related to the presence of abnormal structural changes as assessed by brain magnetic resonance (MR), rather, than to the treatment of epilepsy with focal or generalized epileptic discharges in the EEG, duration of epilepsy, or seizure frequency (more or fewer than 1 seizure a month). The authors found an increase in plasma lipid peroxidation in 52 children with epilepsy, treated with one or more AEDs and abnormal brain MR, compared with 16 healthy children (the difference was significant, p<0.05). No significant differences in anti-oxidant enzymes were found in either group. Patients with well-controlled seizures and children with drugresistant seizures but normal MRs had a higher SOD activity than children in the control group (p<0.05). GSH-Px (an antioxidant) activity was not significantly different in the children with epilepsy compared to the control group.

anti-oxidation enzyme balance, trace elements and electrolytic homeostasis than the odler

Epilepsy Treatment and Nutritional Intervention

http://dx.doi.org/10.5772/57484

27

**4.** Neuroprotectors (trace elements, vitamins and other antioxidants) help to reduce seizureinduced oxygen stress and therefore it is suggested that they should supplement AED treatment. It may be expected that the long-term AED adverse events will be diminished by combination of AED with antioxidants. However, one of the main problems is to find appropriate effective dose and kind of antioxidants restoring equilibrium between

**5.** Since some AEDs, seizures and epileptiform discharges can lead to oxidation – antioxidation imbalance, it seems reasonable to develop new strategies that diminish negative effects of oxygen stress properties in current epilepsy treatment. New AED synthesis,

**6.** Further studies of oxygen stress effects are needed to understand better the mechanisms

**7.** Research on the role of oxygen stress opens a new chapter in epileptology with a hope of prevention of biochemical proceses leading to epileptogenesis, better seizure control and

Epilepsy Diagnostic and Therapeutic Center, Foundation of Epileptology, Warsaw, Poland

[1] Abramov J.P., Wells P.G.: *Embryoprotective role of endogenous catalase in acatalasemic and human catalase-expressing mouse embryos exposed in culture to developmental and phe‐*

[2] Abuhandan M., Calik M., Taskin A., Yetkin I., Selek S., Iscan A.: *The oxidative and an‐ tioxidative status of simple febrile seizure patients*. J. Pak. Med. Assoc., 2013, 63: 594-7.

[3] Akarsu S., Yilmaz S., Ozan S., Kurt A., Benzer F., Gurgoze M.K.: *Effects of febrile seiz‐*

*nytoin-enhanced oxidative stress.* Toxicol. Sci., 2011, 120: 428-438.

*ures on oxidant state in children.* Pediatr. Neurol., 2007, 36: 307-311.

without oxidative effects, would provide better quality of epilepsy medication.

AEDs.

**Author details**

Jerzy Majkowski\*

**References**

oxidative and anti-oxidative processes.

of protective effects of anti-oxidants.

diminish cognitive function impaiment.

Address all correspondence to: fundacja@epilepsy.pl

The authors have no conflict of interest to disclose.

This interesting and heterogeneous picture of enzymatic activity in children with epilepsy and control children suggests that the relationship between various laboratory tests and numerous variables associated with the heterogeneity and treatment of epilepsy are very complex. Although the authors took seizure frequency into consideration, they did not state when blood tests were undertaken relative to seizure occurrence or to an imminent seizure, nor do they report EEG epileptic activity prior to the blood test. This makes it very difficult to monitor the causal relationships between the results of the various tests and their epileptic correlates.

Study of oxygen stress markers in the neocortex of drug-resistant epilepsy patients submitted to epilepsy surgery, supported human findings being in agreement with those found in animal models (Rumia et al., 2013). The concurrent increase in catalase (p<0.01) and decrease in GPx (p<0.05) together with unchanged SOD levels, suggests catalase as the main anti-oxidant enzyme in human epileptic cortex. The substantial increase in the levels of oxidants – 02 (-) and 8-oxo-dG in epileptic patients – in comparison with non-epileptic cortex samples – supports a connection between chronic seizures and ROS-mediated neuronal damage.
