Therapeutic enhancing potential of piracetam with diethylstilbestrol in prevention of grand-mal seizures in rats: inhibition of PI3K/Akt/mTOR signaling pathway and IL-1ß, IL-6, TNF-α cytokines levels.

OBJECTIVE: Epilepsy, a neurodegenerative disorder, continues to throw challenges in the therapeutic management. The current study sought to ascertain if the therapeutic interactions between piracetam and diethylstilbestrol may prevent grand-mal seizures in rats. MATERIALS AND METHODS: Piracetam (PIR; 10 and 20 mg/kg) and diethylstilbestrol (DES; 10 and 20 mg/kg) alone as a low-dose combination were administered to rats for 14 days. The electroshock (MES; 180 mA, 220 V for 0.20 s) was delivered via auricular electrodes on the last day of treatment and rats were monitored for convulsive behavior. To elucidate the mechanism, hippocampal mechanistic target of rapamycin (mTOR) and interleukin (IL)-1ß, IL-6 and tumor necrotic factor-alpha (TNF-α) levels were quantified. Hippocampal histopathology was conducted to study the neuroprotective effect of drug/s. In vitro studies and in silico studies were conducted in parallel. RESULTS: To our surprise, the low dose of the combination regimen of PIR (10 mg/kg) and DES (10 mg/kg) unfolded synergistic anti-seizure potential, with brimming neuroprotective properties. The mechanism could be related to a significant reduction in the levels of hippocampal mTOR and proinflammatory cytokines. The docking scores revealed higher affinities for phosphatidylinositol 3-kinase (PI3K) in co-bound complex, and when docking DES first, while better affinities for protein kinase B (Akt) were revealed when docking PIR first (both drugs bind cooperatively as well). This indicated that the entire PI3K/Akt/mTOR signaling pathway is intercepted by the said combination. In addition, the % of cell viability of HEK-293 cells [pre-exposed to pentylenetetrazol (PTZ)] was increased by 327.29% compared to PTZ-treated cells (toxic control; 85.16%). CONCLUSIONS: We are the first to report the promising efficacy of the combination (PIR 10 mg/kg + DES 10 mg/kg) to restrain seizures and epileptogenic changes induced by electroshock by a novel mechanism involving inhibiting the PI3K/Akt/mTOR signaling.

Raloxifene protects against seizures and neurodegeneration in a mouse model mimicking epilepsy in postmenopausal woman.

Epilepsy in menopausal women presents several challenges in the treatment including an increased risk of seizures due to hormone replacement therapy. We investigated the hypothesis if raloxifene, a selective oestrogen receptor modulator, could be employed to prevent behavioural seizures and morphological alterations in a mouse model mimicking epilepsy in postmenopausal women. Female mice were made ovotoxic by treatment with 4-vinylcyclohexene diepoxide (VCD) to mimic a postmenopausal state. They were then subjected to kainic acid (KA)-induced seizures and neurotoxicity, as assessed by microscopic examination of hippocampus, relevant to human temporal lobe epilepsy. VCD administration (for 15days followed by a drug-free period of 30days) induced ovotoxicity in mice as evidenced by reduced number of primary ovarian follicles. This was accompanied by a 62.4% reduction in serum oestradiol levels. The bone mineral density of ovotoxic mice, however, remained unaffected. Raloxifene (8mg/kg) reduced the seizure severity score in both normal and ovotoxic mice and protected against degeneration induced by KA in the CA3, CA1 sub-fields and hilus of the DG. Hippocampal TGF-ß3 levels were not affected by any of the treatments. We show the potential protective role of raloxifene in preventing seizures and neuronal damage in a mouse model mimicking epilepsy in postmenopausal women which was found unrelated to hippocampal TGF-ß3. Raloxifene might represent a novel therapeutic option for postmenopausal temporal lobe epileptic woman.