NR4A1 Knockdown Suppresses Seizure Activity by Regulating Surface Expression of NR2B

Abstract

Nuclear receptor subfamily 4 group A member 1 (NR4A1), a downstream target of CREB that is a key regulator of epileptogenesis, has been implicated in a variety of biological processes and was previously identified as a seizure-associated molecule. However, the relationship between NR4A1 and epileptogenesis remains unclear. Here, we showed that NR4A1 protein was predominantly expressed in neurons and up-regulated in patients with epilepsy as well as pilocarpine-induced mouse epileptic models. NR4A1 knockdown by lentivirus transfection (lenti-shNR4A1) alleviated seizure severity and prolonged onset latency in mouse models. Moreover, reciprocal coimmunoprecipitation of NR4A1 and NR2B demonstrated their interaction. Furthermore, the expression of p-NR2B (Tyr1472) in epileptic mice and the expression of NR2B in the postsynaptic density (PSD) were significantly reduced in the lenti-shNR4A1 group, indicating that NR4A1 knockdown partly decreased surface NR2B by promoting NR2B internalization. These results are the first to indicate that the expression of NR4A1 in epileptic brain tissues may provide new insights into the molecular mechanisms underlying epilepsy.

GPR40 modulates epileptic seizure and NMDA receptor function

“…The collection of human epileptic brain tissue was previously described ( 47 ). Briefly, 20 neocortical tissues from pharmacoresistant TLE patients and 10 histological normal neocortical tissues from head trauma patients were surgically obtained from The First Affiliated Hospital of Chongqing Medical University.…”

The Phosphodiesterase 10A Inhibitor PF-2545920 Enhances Hippocampal Excitability and Seizure Activity Involving the Upregulation of GluA1 and NR2A in Post-synaptic Densities

“…The suspensions were layered on sucrose (1 M) and centrifuged at 100,000 × g for 1 h at 4°C. Triton-insoluble material (highly enriched in post-synaptic densities) sedimented through the sucrose layer and was re-suspended in the same buffer containing 1% SDS, then stored at -80°C (Dong et al, 2015; Zhang et al, 2016). …”

Interactions between GHRH and GABAARs in the brains of patients with epilepsy and in animal models of epilepsy

“…Immunofluorescence staining was performed using the method described in our previous publication 4 , 24 . The primary antibodies were: rabbit anti-GHRH (1:100, catalog No: ab187512, Abcam, Cambridge, MA, USA), mouse anti-glial fibrillary acidic protein (GFAP) (1:50, catalog number BM0055; Boster Bioengineering, Wuhan, China), mouse anti-Gephyrin (1:50, Abcam, Cambridge, MA, USA), guinea pig anti-microtubule-associated protein 2 (MAP2) (1:200, Sysy, Goettingen, Germany), mouse anti-glutamate decarboxylase 67 (GAD67) (1:100, Abcam, Cambridge, MA, USA), and guinea pig anti-vesicular GABA transporter (VGAT) (1:200, Sysy, Goettingen, Germany).…”

“…Epilepsy is a common chronic neurological disease caused by the abnormal discharge of neurons in the brain and is characterized by short, rigid, repeated neurological dysfunction 1 – 3 . Temporal lobe epilepsy (TLE) is the most common type of adult epilepsy 4 – 6 . According to statistics, approximately 70 million patients are currently diagnosed with epilepsy worldwide 7 .…”