Effects Of Sodium Valproate On Neutrophils’ Oxidative Metabolism And Oxidant Status In Children With Idiopathic Epilepsy

Effects of sodium valproate on neutrophils’oxidative metabolism and oxidant status in children with idiopathic epilepsyEpilepsy is considered one of the most common neurologic disorders in children. It is a chronic dynamic medical problem that often requires long-term antiepileptic drugs (AEDs) therapy. But prolonged AEDs therapy is often associated with a wide range of chronic adverse effects. Recently clinical epidemiology studies show that morbidity and mortality of cardiovascular diseases associated with atherosclerosis in adult epileptic patients with prolonged AEDs therapy are rising. The early vascular changes of atherosclerosis and its risk factors are initiated from childhood and progress with age. Neurologists have shown concern about the prevalence of vascular risk factors and their contribution in the development of atherosclerosis among patients with epilepsy and AEDs therapy. But its mechanism has not been clarified. Oxidative stress is generally considered to play a crucial role in atherosclerosis and polymorphonuclear neutrophils (PMN) may have a causative role in atherogenesis and atheroprogression. As inflammatory cells, PMN can release inflammatory mediators and reactive oxygen species (ROS) which play a pivotal role in the pathogenesis of oxidative stress and atherosclerosis. AEDs can activate PMN, so in this study, we proposed to test what are the effects of long-term AEDs therapy on PMN activation, vascular risk factors, lipid peroxidation and antioxidant biomarkers?Objectives1. To investigate the changes of neutrophilic activation and the activities of myeloperoxidase in epileptic children before and after VPA monotherapy.2. To investigate the activities of antioxidant enzymes including superoxide dismutase, catalase, and glutathione peroxidase in epileptic children with VPA monotherapy.3. To investigate the changes of lipid peroxidation marker malondialdehyde in epileptic children treated with VPA.4. To evaluate the effects of AEDs therapy, time of therapy, seizure types and other factors on these results. So to instruct the clinical use of VPA.Methods1. ObjectsAccording to the diagnostic criteria of ILAE 1981 and ILAE1989, we selected epileptic children whose clinical manifestation and EEG results were in line with the diagnostic criteria in out-patient clinics, and then divided them into two groups: generalized seizures group and partial seizures group.Groups:It was a before and after self control study. Items were detected in newly diagnosed epileptic patients and 6 months,12 months follow up. They were compared with those of healthy children.2. Methods26 newly diagnosed epileptic children with idiopathic epilepsy and 30 healthy children were included in the study. The activation rates of neutrophils and stimulation indexes were detected in patients before and after 6 months,12 months VPA treatment respectively and in all the healthy children by flow cytometry with dihydrorhodamine as fluorochrome. The activities of myeloperoxidase from neutrophils were also detected. Malondialdehyde as an indicator of lipid peroxidation and antioxidant enzymes including superoxide dismutase, catalase, and glutathione peroxidase were measured in plasma respectively.Results1. Genaral informationDuring the study, we included 26 epileptic patients and 30 healthy children according to the including and excluding criteria, within the patients there were 14 boys and 12 girls; 16 generalized seizures and 10 partial seizures. All patients were seizure free after VPA therapy. The ages, sexes, frequency of seizures, white blood cells count and neutrophils between patients did not have any statistical significance.2. Effects of VPA monotherapy on neutrophilic activationThe activation rates of neutrophils in patients treated with VPA were significantly higher and partly showed in the form of double hump on the flow cytometry. After 6 months and 12 months VPA therapy, the activation rates of neutrophils were (11.50±6.52)% and (14.31±5.76)% respectively while the data of control group and before therapy were (5.90±3.77)% and (7.42±3.15)% respectively. The differences had statistical significance (P<0.01). The stimulation indexes of treated patients were lower than the control and untreated groups (P<0.05), which hint that the reserved function of neutrophils were decreased.3. Effects of VPA monotherapy on the activities of myeloperoxidaseThe plasma MPO activities in VPA treated patients were higher than healthy children and untreated group. After 6 months and 12 months VPA therapy, the activities of myeloperoxidase were (28.26±8.99)U/L and (34.28±10.72)U/L respectively while the data of control group and untreated group were (20.87±7.52)U/L and (22.14±6.16)U/L respectively. The differences had statistical significance (P<0.01).In this study, the differences of neutrophilic activation, stimulation indexes and MPO activities between generalized and partial seizures had no statistical significance. So the effects of VPA monotherapy on neutrophilic function had no relationship with the seizure types.4. Effects of VPA monotherapy on the oxidative stress markersThe activities of SOD and CAT were significantly lower than the control and untreated groups. After 6 and 12 months VPA therapy, the activities of SOD were (57.85±9.42) U/ml and (49.77±10.32)U/ml respectively while the data of control group and untreated group were (67.24±10.13) U/ml and (62.54±8.43)U/ml respectively. The differences had statistical significance (P<0.01). The activities of CAT after 6 and 12 months VPA therapy were (6.23±1.37)U/ml and (5.97±1.48)U/ml respectively while the control group was (7.65±1.90)U/ml and untreated group was (6.97±2.06)U/ml(P<0.05). But the levels of GSH-Px between each groups did not have any statistical significance.5. Effects of VPA monotherapy on the lipid peroxidationAfter 6 and 12 months VPA therapy, the levels of MDA were (7.41±1.63) nmol/ml and (8.41±1.84) nmol/ml respectively while the data of control group and untreated group were (5.81±1.36) nmol/ml and (6.29±1.46) nmol/ml respectively. The differences had statistical significance (P<0.01).6. Correlation and regressionFactors associated with MDA levels were analysed with Spearman correlation. The time of treatment, neutrophilic activation and MPO activities were indicators which had positive correlation with the levels of plasma MDA. The coefficients were r=0.488、0.535 and 0.503 (P<0.01). SOD and CAT activities were inversely correlated with MDA levels. The coefficients were r=-0.552 and-0.289 (P<0.01). Other factors such as ages, sexes, seizure types, WBC counts and neutrophils counts had no correlation with MDA levels.Multiple linear regression analysis showed that the time of treatment (X1), the activation rates of neutrophils (X2) and SOD activities (X3) were ultimately in the regression equation:Y=8.482+0.487*X1+0.077*X2-0.052*X3, adjusted R2=0.373. So the injury of oxidative stress was closely associated with the time of treatment and neutrophilic activation.Conclusion1. VPA can activate neutrophils. Neutrophilic activation is positively correlated with the time of VPA treatment.2. VPA can cause oxidative injury and it is positively correlated with neutrophilic activation.3. The effects of VPA therapy on neutrophilic activation may have no relationship with the seizure types.