Epilepsy is characterized by recurrent seizures due to a perturbed balance between glutamate and GABA neurotransmission. Our goal is to reveal the molecular mechanisms of the changes upon repeated challenges of this balance, suggesting knowledge-based neuroprotection. To address this goal, a set of metabolic indicators in the post-seizure rat brain cortex is compared before and after pharmacological kindling with pentylenetetrazole (PTZ). Vitamins B1 and B6 supporting energy and neurotransmitter metabolism are studied as neuroprotectors. PTZ kindling increases the seizure severity (1.3 fold, p < 0.01), elevating post-seizure rearings (1.5 fold, p = 0.03) and steps out of the walls (2 fold, p = 0.01). In the kindled vs. non-kindled rats, the post-seizure p53 level is increased 1.3 fold (p = 0.03), reciprocating a 1.4-fold (p = 0.02) decrease in the activity of 2-oxoglutarate dehydrogenase complex (OGDHC) controlling the glutamate degradation. Further, decreased expression of deacylases SIRT3 (1.4 fold, p = 0.01) and SIRT5 (1.5 fold, p = 0.01) reciprocates increased acetylation of 15 kDa proteins 1.5 fold (p < 0.01). Finally, the kindling abrogates the stress response to multiple saline injections in the control animals, manifested in the increased activities of the pyruvate dehydrogenase complex, malic enzyme, glutamine synthetase and decreased malate dehydrogenase activity. Post-seizure animals demonstrate correlations of p53 expression to the levels of glutamate (r = 0.79, p = 0.05). The correlations of the seizure severity and duration to the levels of GABA (r = 0.59, p = 0.05) and glutamate dehydrogenase activity (r = 0.58, p = 0.02), respectively, are substituted by the correlation of the seizure latency with the OGDHC activity (r = 0.69, p < 0.01) after the vitamins administration, testifying to the vitamins-dependent impact of the kindling on glutamate/GABA metabolism. The vitamins also abrogate the correlations of behavioral parameters with seizure duration (r 0.53–0.59, p < 0.03). Thus, increased seizures and modified post-seizure behavior in rats after PTZ kindling are associated with multiple changes in the vitamin-dependent brain metabolism of amino acids, linked to key metabolic regulators: p53, OGDHC, SIRT3 and SIRT5.

Mammalian glutamate dehydrogenase (GDH) is an indispensable metabolic enzyme. GDH duplication has led to the presence of two paralogs, GDH1 and GDH2, in apes. Multiple GDH pseudogenes are also present in the human genome. The novel GDH2, supposed to be a target of positive selection, differs from GDH1 in regulation and is believed to be tightly linked to brain development. Although the differences of modern human GDH2 from GDH2 of other apes have been studied, the evolution of ancient human GDH2 remains a blank space. The goal of this work was to elucidate GDH2 evolution in the genus Homo using the accumulated data on the ancient genomes with high coverage—three Neanderthal and one Denisovan genome. Such analysis clarifies the difference between GDH2 of the last common ancestor of humans and chimpanzees and all Homo to be in M468L substitution, localized in the regulatory “antenna” region of the protein. A few novel missense mutations have been found in Denisovan and Altai Neanderthal GDH2, namely R76H, present in both genomes, and Denisovan-specific T154P, I358L, and S498A substitutions. Another mutation, R352K, has likely occurred independently in modern humans and later Neanderthals. The potential impact of these mutations was estimated using GDH2 structural data and evidence from contemporary medical data. All substitutions are supposed to be benign, with only the S498A GDH2 substitution connected to Parkinson’s disease with late onset. Additionally, the ancient genomes were revealed to have all GDH pseudogenes present in modern humans, including the RNA-coding ones. The GLUD1P3 RNA expression was found to correlate negatively with GDH1 in human tissues. A possible regulatory role has been proposed, and the GLUD1P3 RNA sequence identity in all the studied human genomes suggests its conservation in the genus Homo.