Investigation of antiepileptic potentials of usnic acid and some lichen species on the behavioral and biochemical levels in pentylenetetrazole-induced kindling model of epilepsy

In this study, the effects of various lichen and usnic acid applications on seizure scores and biochemical parameters in brain tissue in rats with epilepsy model was investigated. For this aim, 91 rats were divided into 13 groups, each containing 7 rats, which were: control, pentylenetetrazole (PTZ) (35 mg/kg), PTZ Valproic acid (100 mg/kg), PTZ Dolichousnea longissima (200 mg/kg), PTZ Dolichousnea longissima (400 mg/kg), PTZ Xanthoparmelia somloensis (50 mg/kg), PTZ Xanthoparmelia somloensis (200 mg/kg), PTZ Cetraria islandica (250 mg/kg), PTZ Cetraria islandica (500 mg/kg), PTZ Pseudevernia furfuracea (250 mg/kg), PTZ Pseudevernia furfuracea (500 mg/kg), PTZ usnic acid (50 mg/kg), and PTZ usnic acid (200 mg/kg). All items were applied with an interval of 120 minutes for a period of one week. Seizure detection, seizure scores and total seizure duration of each group was recorded. After the applications, oxidative stress parameters and acetylcholinesterase enzyme activity in the brain tissue of rats were measured. There was no difference between the groups in the 1st, 2nd, and 3rd injections (p>0.05). Starting from the 4th injection, the seizure score was significantly higher in the PTZ group compared to the control group (p<0.05). When the effects on locomotor activity were evaluated, no difference was found between any group (p>0.05). In PTZ applied groups, an increase in lipid and protein oxidation as well as a decrease in antioxidant and acetylcholine esterase levels were observed (p<0.05). Valproic acid, high concentration of lichen extract applications and high and low concentration of usnic acid applications were found to reverse this situation(p<0.05). As a result, various lichen extracts and usnic acid were shown to reduce behavioral symptoms and oxidative stress of epilepsy, with a preventive effect on the complications of epilepsy.

Keyword: brain; Epilepsy; lichen; oxidative stress; pentylenetetrazole; seizure scores