KAIST 생명과학과동창회
  • News & Events
  • News

News

Astrocytes eat connections to maintain plasticity in adult brains

 

by The Korea Advanced Institute of Science and Technology (KAIST) 

  

 

    Astrocytes eat connections to maintain plasticity in adult brains

A 3-D image showing our synapse phagocytosis reporter in mouse hippocampus

 

Developing brains constantly sprout new neuronal connections called synapses as they learn and remember. Important connectionsthe ones that are repeatedly introduced, such as how to avoid dangerare nurtured and reinforced, while connections deemed unnecessary are pruned away. Adult brains undergo similar pruning, but it was unclear how or why synapses in the adult brain get eliminated.                      

    

Now, a team of KAIST researchers has found the mechanism underlying plasticity and, potentially, neurological disorders in adult brains. They published their findings on December 23 in Nature.

    

"Our findings have profound implications for our understanding of how neural circuits change during learning and memory, as well as in diseases," said paper author Won-Suk Chung, an assistant professor in the Department of Biological Sciences at KAIST. "Changes in synapse number have strong association with the prevalence of various neurological disorders, such as autism spectrum disorder, schizophrenia, frontotemporal dementia, and several forms of seizures."

    

Gray matter in the brain contains microglia and astrocytes, two complementary cells that, among other things, support neurons and synapses. Microglial are a frontline immunity defense, responsible for eating pathogens and dead cells, and astrocytes are star-shaped cells that help structure the brain and maintain homeostasis by helping to control signaling between neurons. According to Professor Chung, it is generally thought that microglial eat synapses as part of its clean-up effort in a process known as phagocytosis.

    

"Using novel tools, we show that, for the first time, it is astrocytes and not microglia that constantly eliminate excessive and unnecessary adult excitatory synaptic connections in response to neuronal activity," Professor Chung said. "Our paper challenges the general consensus in this field that microglia are the primary synapse phagocytes that control synapse numbers in the brain."

  

Professor Chung and his team developed a molecular sensor to detect synapse elimination by glial cells and quantified how often and by which type of cell synapses were eliminated. They also deployed it in a mouse model without MEGF10, the gene that allows astrocytes to eliminate synapses. Adult animals with this defective astrocytic phagocytosis had unusually increased excitatory synapse numbers in the hippocampus. Through a collaboration with Dr. Hyungju Park at KBRI, they showed that these increased excitatory synapses are functionally impaired, which cause defective learning and memory formation in MEGF10 deleted animals.

 

"Through this process, we show that, at least in the adult hippocampal CA1 region, astrocytes are the major player in eliminating synapses, and this astrocytic function is essential for controlling synapse number and plasticity," Chung said.

    

Professor Chung noted that researchers are only beginning to understand how synapse elimination affects maturation and homeostasis in the brain. In his group's preliminary data in other brain regions, it appears that each region has different rates of synaptic elimination by astrocytes. They suspect a variety of internal and external factors are influencing how astrocytes modulate each regional circuit, and plan to elucidate these variables.

 

"Our long-term goal is understanding how astrocyte-mediated synapse turnover affects the initiation and progression of various neurological disorders," Professor Chung said. "It is intriguing to postulate that modulating astrocytic phagocytosis to restore synaptic connectivity may be a novel strategy in treating various brain disorders."

 

https://www.sciencedaily.com/releases/2020/12/201224090406.htm 

https://sciencecodex.com/astrocytes-eat-connections-maintain-plasticity-adult-brains-664004  

https://medicalxpress.com/news/2020-12-astrocytes-plasticity-adult-brains.html 

https://www.news-medical.net/news/20201224/Researchers-find-mechanism-underlying-plasticity-in-adult-brains.aspx 

https://www.miragenews.com/astrocytes-eat-connections-to-maintain-plasticity-in-adult-brains/ 

https://microbiozindia.com/health-news/researchers-locate-mechanism-underlying-plasticity-in-grownup-brains/


List of Articles
번호 제목 글쓴이 날짜 조회 수
130 임대식 교수, 교과부 ' 창의적연구진흥사업'의 신규 지원과제에 선정! 과사무실 2010.04.21 12366
129 박태관 교수, 2010년도 삼성 고분자 학술상 수상! 과사무실 2010.04.12 9986
128 제1회 젊은 파스퇴르상 카이스트 석권! 과사무실 2010.03.02 11736
127 2010년 개교 39주년 기념 우수교원 포상 과사무실 2010.02.11 11444
126 허원도 교수, ECLIPSE 기술 개발 PNAS지 게재 과사무실 2010.02.09 12963
125 박태관 교수, 획기적인 핵산 유전자 치료제 전달시스템 개발 과사무실 2010.01.29 12349
124 학사과정 강병권 학생, 2009년 인성장학생 공로부문 선정! 과사무실 2010.01.08 12413
123 서연수 교수, 2009년 연구윤리 확립 유공자 교육과학기술부 장관 표창 수상! 과사무실 2010.01.06 12032
122 생명과학과 신임교원 강석조 박사 소개 (2010.01.01) 과사무실 2009.12.29 16254
121 BK21 생물사업단, 2단계 사업 1,2,3차년도 연차평가 생물분야 연속 1위! 과사무실 2009.12.29 12958
120 권석규 학생(김은준 교수 lab), 2009' 석림학술장학재단 장학생으로 선정! 과사무실 2009.12.22 12882
119 박태관 교수, 과기정보硏 ‘지식창조대상’ 수상 과사무실 2009.12.09 12165
118 주형석 박사와 김은진 학생(강창원 교수 Lab), ‘2009 캠퍼스 특허전략 유니버시아드 대회’에서 기업 CEO상을 수상! 과사무실 2009.12.01 17575
117 한진희 교수, 원혜정 학생(김은준 교수 Lab) 2009' 청암 과학펠로 선정! 과사무실 2009.11.27 14924
116 강창원 교수, (통합)생화학분자생물학회 2010년도 회장 선임 과사무실 2009.11.05 12433
115 생명과학과 신임교원 한진희 박사 소개 (2009.10.01) 과사무실 2009.10.06 16347
114 목혜정 박사와 이수현 학생(박태관 교수님 Lab), 로슈 마르코 폴로 심포지움에서 최우수 포스터상 수상! 과사무실 2009.09.22 13627
113 김은준 교수팀, 시냅스 가소성 조절 단백질 발견 과사무실 2009.09.14 11411
112 생명과학과 신임교원 오병하 박사 부임 소개 (2009.9.1) 과사무실 2009.09.10 14202
111 생명과학과 신임교원 David Helfman 박사 부임 소개 (2009.8.1) 과사무실 2009.09.10 12098
Board Pagination Prev 1 ... 11 12 13 14 15 16 17 18 19 20 ... 22 Next
/ 22