Gentiopicroside alleviated epileptogenesis in immature rats through inactivation of NLRP3 inflammasome by inhibiting P2X7R expression

Objectives: This study aimed to elucidate the effects of Gentiopicroside (Gent) on epileptogenesis and underlying mechanisms.

Methods: The status epilepticus (SE) model was established by intraperitoneal (i.p.) injection of lithium chloride (127mg/kg) and pilocarpine (50mg/kg) in immature rats. HAPI microglial cellular inflammation model was induced by lipopolysaccharide (LPS, 1μg/mL) and adenosine triphosphate (ATP, 5mM). The differential concentrations of Gent were used to pretreat animal (200, 400, and 800mg/kg) and model cells (50, 100, and 200μM). Epileptic discharges were assessed by electroencephalography (EEG) and Racine scale. Changes in spatial memory function were measured using the Morris water maze task test. Nissl and FJB staining were employed to assess the damage to hippocampus tissues. ELISA was used to detect the production of IL-1β, IL-18, and TNF-α. The expressions of P2X7R and NLRP3 were detected by q-PCR, immunofluorescence staining, and Western blot, and cell viability was determined by cell counting kit-8 (CCK-8).

Results: Lithium chloride and pilocarpine (LICL-PILO) induced abnormal EEG activities, behavioral alterations, brain damage, and inflammatory responses in immature rats. However, Gent pretreatment significantly reduced the neuronal damage and spatial memory dysfunction induced by LICL-PILO. Additionally, Gent suppressed the production of inflammatory cytokines and inhibited the expression of P2X7R, NLRP3, ASC, and Caspase-1 in LPS/ATP-induced HAPI microglial cells.

Discussion: Gent intervention could improve epileptogenesis in immature rats partially due to suppressing P2X7R and NLRP3 inflammasome.

Gentiopicroside; NLRP3 inflammasome; P2X7R; Pediatric epilepsy; inflammation; status epilepticus.