Prof. Xiao-Ming Li's group Revealed a Novel Mechanism of Rett Syndrome Mediated by Cholinergic Syste

2016-05-04   |  

Qiqi is a three-and-a-half years old lovely girl with a sweet smile. Unfortunately, she is not able to speak,chew,walk and even showed no response to her mother’s voice. This disease is called Rett syndrome (RTT). Sincethere is no treatment available for RTT nowadays, it is also called “An Incurable Disease of the Century.” 
Rett syndrome is an autism spectrum disorder that affects nearly 1 in 10,000 females. A research conducted by the team of Prof. Xiao-Ming Li from School of Medicine revealed that α7 receptors in hippocampus could be the potential target for treatment of RTT.
The finding entitled ” Loss of MeCP2 in cholinergic neurons causes part of RTT-like phenotypes via α7 receptor in hippocampus” was published in Cell Research on April 22th, 2016. They investigated the role of cholinergic system in the pathogenesis of RTT and pointed out the potential target for treatment of RTT. These results indicate for the first time that the direct involvement of cholinergic system in some aspects of RTT pathogenesis. They also find the molecular target and provide new thought for the treatment of RTT and other relative neuropsychiatric disorders. 
“Cholinergic system in the brain is an essential neuromodulation system related to learning and memory. The failure of central cholinergic system can affect sleep and even cause neurological disorders like Parkinson disease.” Prof. Xiao-Ming Li introduced. The research interest of Li’s lab focus on understanding the molecular mechanisms underlying different neuropsychiatry disorders and identifying targets to develop therapeutic strategies for treatment. 
They found that conditional deletion of MeCP2 in cholinergic neurons caused behavioral deficits, including impaired social interaction, anxiolytic behaviors and seizure penetrance. Furthermore, they identified that impairment of the α7 nicotinic signaling pathway from the BF cholinergic neurons to the hippocampus was the key factor mediating the observed phenotypes. One of the first author Ying Zhang stated that “This phenomenon reminded us that probably we can improve the behavioral score of transgenic mice if we stimulate the remaining cholinergic receptors with specific drugs.” 
Nicotine is a kind of alkaloid existed in solanaceae plants. Delivery of nicotine in the hippocampus rescued behavioral deficits manifested in transgenic mice. Since Nicotine is the primary psychoactive component of tobacco.some people maywonder whether smoking could treat RTT or improve several symptoms of RTT?. Ying Zhang believed that it is very possible sinceNicotine in cigarettes can reach the central nervous system through the blood brain barrier. However,, it’s further study is still needed to conduct to reach the final conclusion.”. 
Ying Zhang and Shu-Xia Cao who are Ph.D. candidates are co-first authors of this paper. This study was supported by grants from the National Science Foundation of China for Distinguished Young Scientists, Key Project of the China National Natural Science Foundation and Major Research Program of Ministry of Science and Technology of China.