apelin-13-peptide and Seizures

In spite of recent advances in the treatment of epilepsy, up to 35% of people living with the condition do not respond to accessible anti-epileptic drugs (AEDs) and continue to experience regular, devastating and potentially life-threatening seizures. Neuronal death is a significant feature of epilepsy in humans and experimental models. It has been reported that apelin, an endogenous ligand for the angiotensin-1-like receptor (APJ), has anticonvulsive as well as protective effects in some neurodegenerative situations. In the current study, we investigated the effects of apelin-13 on pentylenetetrazole (PTZ)-induced neurotoxicity in rat's brain primary culture. Cell injury was induced by 20mM PTZ and the cells viability was examined by MTT assay. Intracellular calcium, reactive oxygen species (ROS) and mitochondrial membrane potential were determined by fluorescence spectrophotometry methods. Markers of apoptosis were determined by immunohistochemistry. The data showed that PTZ caused a loss of cell viability and mitochondrial membrane potential. In addition, intracellular reactive oxygen species, intracellular calcium, COX-2 and caspase-3 positive cells were increased in PTZ-treated cells. Incubation of the cells with aplein-13 (10μM) elicited protective effect and reduced markers of cell damage and death. The results suggest that apelin-13 has protective effects against PTZ-induced toxicity and such effects are accompanied by its calcium blocking, antioxidant and, anti-inflammatory and anti-apoptotic properties.

Topics: Animals; Anti-Inflammatory Agents; Anticonvulsants; Antioxidants; Apoptosis; Calcium; Caspase 3; Cell Survival; Coculture Techniques; Cyclooxygenase 2; Epilepsy; Intercellular Signaling Peptides and Proteins; Membrane Potential, Mitochondrial; Neuroglia; Neurons; Pentylenetetrazole; Protective Agents; Rats; Reactive Oxygen Species; Seizures

Epilepsy is a common neurological disorder with no effective treatment or cure. Neuropeptide apelin is an endogenous ligand of angiotensin receptor-like 1 (APJ). It has been shown that apelin has protective and anti-neurodegenerative properties. This study was designed to evaluate the effect of apelin-13 on pentylenetetrazole (PTZ)-induced rat model of seizure. Adult male Wistar rats were divided into the experimental groups as follows: control group receiving PTZ; apelin-treated group which received apelin-13 before PTZ; apelin+F13A-treated group which received apelin-13 plus the apelin receptor antagonist (F13A) before PTZ; apelin+naloxone group which received apelin-13+naloxone before PTZ. Behavioral scoring was used to access seizure. The expression level of APJ was measured by western blotting. Neuronal degeneration, apoptosis and astrocyte activation were evaluated by vanadium acid fuchsin (VAF) staining and immunohistochemistry. Our data demonstrated that apelin-13 pretreatment significantly inhibited seizure threshold (p<0.001) and tonic-clonic latency (p<0.001) compared with the control group. In addition, PTZ-induced up-regulation of APJ was attenuated by apelin-13 treatment. Histological and immunohistochemical findings also showed that apelin-13 could protect cortical neurons against PTZ-induced neuroinflammation and apoptosis. In conclusion, apelin-13 has anticonvulsive and neuroprotective properties against PTZ-induced seizure in rats and provided a new pharmacological aspect of the neuropeptide apelin.

Topics: Animals; Anticonvulsants; Apelin Receptors; Apoptosis; Astrocytes; Brain; Disease Models, Animal; Glial Fibrillary Acidic Protein; Intercellular Signaling Peptides and Proteins; Male; Nerve Degeneration; Neurons; Neuroprotective Agents; Pentylenetetrazole; Rats, Wistar; Receptors, G-Protein-Coupled; Seizures