Background: Homer is a family of post synaptic density proteins functionally and physically attached to target proteins at proline-rich sequences. Reducing Homer1b/c expression has been shown in previous studies to be protective against excitotoxic insults, implicating Homer1b/c in the physiological regulation of aberrant neuronal excitability. Methods: To test the efficacy of a Homer1b/c reducing therapy for disorders with a detrimental hyperexcitability profile in mice, we used small interfere RNA (siRNA) to decrease endogenous Homer1b/c expression in mouse hippocampus. The baseline motor and cognitive behavior was measured by sensorimotor tests, Morris water maze and elevated plus maze tasks. The anti-epileptic effects of Homer1b/c knockdown were determined in two chemically induced seizure models induced by Picrotoxin (PTX) or pentylenetetrazole (PTZ) administration. Results: The results of sensorimotor tests, Morris water maze and elevated plus maze tasks showed that Homer1b/c reduction had no effect on baseline motor or cognitive behavior. In two chemically induced seizure models, mice with reduced Homerb/c protein had less severe seizures than control mice. Total Homer1b/c protein levels and seizure severity were highly correlated, such that those mice with the most severe seizures also had the highest levels of Homer1b/c. In addition, the phosphorylation of mammalian target of rapamycin (mTOR) and its target protein 56 was significantly inhibited in Homer1b/c down-regulated mice. Homer1b/c knockdown-induced inhibition of mTOR pathway was partially ablated by the metabotropic glutamate receptor 5 (mGluR5) agonist CHPG. Conclusion: Our results demonstrate that endogenous Homer1b/c is integral for regulating neuronal hyperexcitability in adult animals and suggest that reduction of Homer1b/c could protect against chemically induced seizures through inhibition mTOR pathway. Copyright (C) 2015 S Karger AG, Basel
基金:
the National Natural Science Foundation of China (No.81201004).
第一作者机构:[a]Department of Neurological Disease, Xi’an Central Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi,[b]Department of Rehabilitation, Xuanwu Hospital Capital Medica University, Xicheng, Beijing, China
通讯作者:
通讯机构:[*1]Department of Neurological Disease, Xi’an Central Hospital, Xi’an Jiaotong University, Xi'an, Shaanxi Province 710032 (China)
推荐引用方式(GB/T 7714):
Lei Cao,Ye Tian,Yi Jiang,et al.Down-Regulation of Homer1b/c Protects Against Chemically Induced Seizures Through Inhibition of mTOR Signaling[J].CELLULAR PHYSIOLOGY AND BIOCHEMISTRY.2015,35(4):1633-1642.doi:10.1159/000373977.
APA:
Lei Cao,Ye Tian,Yi Jiang,Ge-Juan Zhang,Hui Lei&Zheng-Li Di.(2015).Down-Regulation of Homer1b/c Protects Against Chemically Induced Seizures Through Inhibition of mTOR Signaling.CELLULAR PHYSIOLOGY AND BIOCHEMISTRY,35,(4)
MLA:
Lei Cao,et al."Down-Regulation of Homer1b/c Protects Against Chemically Induced Seizures Through Inhibition of mTOR Signaling".CELLULAR PHYSIOLOGY AND BIOCHEMISTRY 35..4(2015):1633-1642