Neuroprotective effects of Pinus eldarica in a mouse model of pentylenetetrazole-induced seizures

Perampanel increases seizure threshold in pentylenetetrazole-kindled mice and improves behavioral dysfunctions by modifying mRNA expression levels of BDNF/TrkB and inflammatory markers

Perampanel (PER), a novel 3rd-generation antiseizure drug that modulates altered post-synaptic glutamatergic storming by selectively inhibiting AMPA receptors, is recently approved to treat intractable forms of seizures. However, to date, presumably consequences of long-term PER therapy on the comorbid deleterious psychiatric disturbances and its correlation with neuroinflammatory parameters are not fully investigated in chronic models of epilepsy. Therefore, we investigated the real-time effect of PER on brain electroencephalographic (EEG) activity, behavioral alterations, redox balance, and relative mRNA expression in pentylenetetrazole (PTZ) induced kindling. Male BALB/c mice were pretreated with PER (0.125, 0.25, and 0.5 mg/kg) for 3 weeks and challenged with 11 injections of PTZ at the sub-threshold dose of 40 mg/kg every other day. vEEG from implanted cortical electrodes was monitored to elucidate seizure propagation and behavioral manifestations. Recorded EEG signals exhibited that PER 0.5 mg/kg pretreatment exceptionally impeded the onset of sharp epileptic spike-wave discharges and associated motor symptoms. Additionally, qEEG analysis showed that PER prevented alterations in absolute mean spectral power and reduced RMS amplitude of epileptogenic spikes vs PTZ control. Furthermore, our outcomes illustrated that PER dose-dependently attenuated PTZ-evoked anxiety-like behavior, memory deficits, and depressive-like behavior that was validated by a series of behavioral experiments. Moreover PER, significantly reduced lipid peroxidation, AChE, and increased levels of SOD and total thiol in the mice brain via AMPAR antagonism. Post-PTZ kindling provoked overstimulation of BDNF/TrkB signaling and increased release of pro-inflammatory cytokines that were reversed by PER with suppression of iNOS in brain immune cells. In conclusion, our findings highlight that PER might play an auspicious preventive role in the proepileptic transformation of brain circuits via suppression of BDNF/TrkB signaling and reduced transcriptional levels of neuroinflammatory markers leading to improvised epilepsy-induced neurobehavioral and neurochemical effects.

Labdane-type Diterpenes from Pinus eldarica Needles and Their Anti-Helicobacter pylori Activity

Pinus eldarica is a medicinal tree used in traditional herbal medicine for the treatment of bronchial asthma and various skin diseases. As part of our ongoing search for bioactive phytochemicals with novel structures in natural products, we performed a phytochemical analysis of the methanol (MeOH) extract from P. eldarica needles collected in Iran. Phytochemical investigation of the MeOH extract, aided by liquid chromatography-mass spectrometry-based analysis, resulted in the isolation and identification of three labdane-type diterpenes (1-3), including a new and relatively unique norlabdane-type diterpene with a peroxide moiety, eldaricoxide A (1). The chemical structures of the isolated labdane-type diterpenes were elucidated by analyzing the spectroscopic data from 1D and 2D NMR and high-resolution electrospray ionization-mass spectrometry. The absolute configuration of eldaricoxide A (1) was established by employing a computational method, including electronic circular dichroism calculation and specific optical rotation. An anti-Helicobacter pylori test was conducted, where compound 3 exhibited the most potent antibacterial activity against H. pylori strain 51, inducing 72.7% inhibition (MIC₅₀ value of 92 μM), whereas eldaricoxide A (1) exhibited moderate antibacterial activity against H. pylori strain 51, inducing 54.5% inhibition (MIC₅₀ value of 95 μM). These findings demonstrated that the identified bioactive labdane-type diterpenes 1 and 3 can be applied in the development of novel antibiotics against H. pylori for the treatment of gastric and duodenal ulcers.

Neuroprotective effects of the fractions of Ocimum basilicum in seizures induced by pentylenetetrazole in mice

Objective

Neuroprotective and antioxidant effects of Ocimum basilicum (O. basilicum) against pentylenetetrazole (PTZ)-induced seizures were investigated.

Materials and Methods

Mice were divided as follows: (Group 1) Control, (Group 2) PTZ, (Groups 3-5) 50,100 and 200 mg/kg hydro-ethanolic (HE) extract, and (Groups 6-8) 200 mg/kg ethyl-acetate (EAF), N-hexane (NHF) and water (WF) fractions. Minimal clonic seizures (MCS) and generalized tonic-clonic seizures (GTCS) latencies were measured. Biochemical and histological studies were done.

Results

MCS and GTCS latency in HE groups were longer than the PTZ group (p<0.05 to p<0.001). EAF and NHF prolonged the onset of MCS and GTCS (p<0.001). PTZ increased malondialdehyde (MDA) and dark neuron (DN) production while decreased thiol, catalase (CAT) and superoxide dismutase (SOD) (p<0.05 to p<0.001). Pre-treatment by HE and all fractions of the plant attenuated MDA and DN while increased thiol, CAT and SOD (p<0.01 to p<0.001).

Conclusion

EAF and NHF had anticonvulsant properties. The extract and fractions protected the brain from PTZ-induced oxidative damages and showed neuroprotective effects.