Shared metabolic pathways in epilepsy and plant immunity: From evolution to diet.

Epilepsy is a widespread neurological disorder characterized by recurrent seizures resulting from abnormal electrical activity in the brain. The origin and severity of these seizures vary depending on the brain regions involved. A key factor influencing seizure susceptibility is vitamin B6, an essential cofactor in neurotransmitter metabolism, where both deficiency and excess can lead to adverse health outcomes. Vitamin B6 homeostasis is regulated in part by Δ1-piperideine-6-carboxylic acid (P6C), a metabolite of lysine catabolism that irreversibly inactivates B6 vitamers. Notably, plants synthesize vitamin B6 de novo and generate P6C during lysine breakdown. Similar to its effects in humans, increase in P6C disrupts cellular metabolism and weakens immune responses in plants. These striking parallels are attributable to conserved metabolic pathways derived from ancient bacterial enzymes that govern vitamin B6 biosynthesis and lysine degradation. This review explores the biochemical basis of epilepsy and highlights the role of plant-derived nutrients, particularly vitamin B6 in supporting human neurological health, while offering evolutionary perspectives on shared metabolic vulnerabilities.