Baicalein Alleviates Lithium-Pilocarpine-Induced Status Epilepticus by Regulating DNMT1/GABRD Pathway in Rats.

BACKGROUND: Epilepsy is a common disease of the nervous system. Recent advances in epigenetics have revealed DNA methylation as a key mechanism in epilepsy pathogenesis, particularly through dysregulation of GABAergic signaling. Baicalein has been shown to have anticonvulsant and neuroprotective effects. However, its epigenetic regulatory effects on GABA receptor function remain unexplored. METHODS: The status epilepticus (SE) model was induced by lithium chloride-pilocarpine (LiCl-PILO) in Sprague-Dawley (SD) rats. The rats were divided into control group, epileptic SE group and baicalein intervention group. Morris water maze (MWM) test, Nissl staining, immunofluorescence and enzyme-linked immunosorbent assay (ELISA) were used to detect cognitive functions and neuronal damage. Online sites, chromatin immunoprecipitation (ChIP) and western blotting were used to identify DNA methyltransferase 1 (DNMT1)-mediated methylation of gamma-aminobutyric acid type A receptor subunit delta (GABRD) promoter region. RESULTS: Baicalein treatment significantly prolonged the latency of SE onset and seizure onset, and improved the development of epilepsy. Meanwhile, baicalein improved the cognitive impairment in rats induced by LiCl-PILO. After treatment with baicalein, a sustained elevation in the number of neurons and NeuN levels was observed, along with a decrease in the contents of tumor necrosis factor -alpha (TNF-α), interleukin-1β (IL-1β), and ionized calcium-binding adapter molecule 1 (Iba-1) in the hippocampus. Mechanistically, baicalein interacted with DNMT1 to suppress GABRD promoter region methylation, thus increasing GABRD protein level in the hippocampus of rats induced by LiCl-PILO. CONCLUSION: This study identifies DNMT1/GABRD axis as a novel epigenetic target for epilepsy intervention. Baicalein's ability to enhance tonic inhibition through demethylation of GABRD provides a groundbreaking strategy for drug-resistant epilepsy.