The effect of subchronic supplementation with folic acid on homocysteine induced seizures

Influence of folic acid on the CNS is still unclear. Folate has a neuroprotective effect, while on the other hand excess folate can exacerbate seizures in epileptics. The aim of the present study was to examine the effect of subchronic administration of folic acid on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone induced seizures in adult rats. The activity of Na+/K+-ATPase and Mg2+-ATPase in different brain regions was investigated. Adult male Wistar rats were divided into groups: 1. Controls (C, 0.9% NaCl); 2. DL homocysteine-thiolactone 8.0 mmol/kg (H); 3. Subchronic supplementation with folic acid 5 mg/kg for 7 days (F) and 4. Subchronic supplementation with F + single dose of H (FH). Seizure behaviour was assessed by incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0–4. For EEG recordings, three gold-plated recording electrodes were implanted into the skull. Subchronic supplementation with folic acid did not affect seizure incidence, median number of seizure episodes and severity in FH, comparison with H (p > 0.05). The majority of seizure episodes in all groups were of grade 2. There were no significant differences in lethal outcomes at 24 h upon H injection in the FH vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in the FH vs. H group. Subchronic folic acid administration did not exacerbate H induced seizures and completely recovered the activity of ATPases

Convulsive properties of D,L homocysteine and D,L homocysteine thiolactone in adult rats

Introduction: Hyperhomocysteinemia is related to epileptogenesis and suboptimal control of seizures in the patients with epilepsy. Available data suggest that homocysteine can be harmful to human cells because of its metabolic conversion to homocysteine thiolactone, a reactive thioester. The aim of the study was to investigate the convulsive properties of equimolar concentrations of D,L homocysteine and D,L homocysteine thiolactone in adult rats. Methods: Adult male Wistar rats were divided into following groups: 1. saline-treated (C, n=10), 2. D, L homocysteine 8 mM/kg, i.p. (H; n=8), and 3. D,L homocysteine-thiolactone (Ht; n=8). Seizure behavior was assessed by the incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0-4.Results: There were no behavioural signs of seizure activity in C group. The incidence of convulsions was lower in group H comparing to the Ht group but statistical significance was not attained. Latency to the first seizure onset was significantly higher in H comparing to the Ht group (p<0.01). Median number of seizure episodes and severity of seizure episodes per rat were significantly lower in H comparing to Ht group.Conclusion: Our findings suggest that D,L homocysteine thiolactone exerts stronger convulsive effect comparing to the equimolar concentration of D,L homocysteine

Exercise Decreases Susceptibility to Homocysteine Seizures: the Role of Oxidative Stress

The aim of the study was to examine the effects of chronic exercise training on seizures induced by homocysteine thiolactone (HCT) in adult rats. Rats were assigned to: sedentary control; exercise control; sedentary +HCT; exercise + HCT group. Animals in the exercise groups ran 30 min daily on a treadmill for 30 consecutive days (belt speed 20 m/min), while sedentary rats spent the same time on the treadmill (speed 0 m/min). On the 31st day, the HCT groups received HCT (8.0 mmol/kg), while the control groups received vehicle. Afterwards, convulsive behavior and EEG activity were registered. Lipid peroxidation, superoxide dismutase (SOD) and catalase (CAT) activity were ascertained in the rat hippocampus. No signs of seizures were registered in sedentary and exercise control rats. Seizure latency was increased, while number of seizure episodes and spike-and-wave discharges (SWD) in EEG were decreased in the exercise + HCT compared to the sedentary +HCT group. Seizure incidence, the severity thereof and duration of SWDs were not significantly different between these groups. Exercise partly prevented increase of lipid peroxidation and decrease of the SOD and CAT activity after HCT administration. These results indicate beneficial effects of exercise in model of HCT induced seizures in rats, what could be, at least in part, a consequence of improved antioxidant enzymes activity

The effect of subchronic supplementation with folic acid and L-arginine on homocysteine-induced seizures

The aim of the present study was to examine the effect of subchronic co-administration of folic acid (F) and L-arginine (A) on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone (H) induced seizures in adult rats. The activity of membrane ATPases in different brain regions were also investigated. Rats were treated with F, A, or vehicle for 15 days (regimen: F 5 mg/kg + A 500 mg/kg (F5A500); F 10 mg/kg + A 300 mg/kg (F10A300)). Seizures were elicited by convulsive dose of H (H, F5A500H, F10A300H) Subchronic supplementation with F and A did not affect seizure incidence, number of seizure episodes, and severity in F5A500H and F10A300H groups vs. H group. However, a tendency to increase latency and decrease the number of seizure episodes was noticed in the F10A300H group. EEG mean spectral power densities during ictal periods were significantly lower in F10A300H vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in rats treated with F and A. We can conclude that subchronic supplementation with folic acid and L-arginine has an antiepileptic effect in DL homocysteine thiolactone induced epilepsy.2nd European-Section Meeting of the International-Academy-of-Cardiovascular-Sciences (IACS), Oct 08-10, 2015, Belgrade, Serbi