Article
Neurosciences
Minghua Li, Jessica L. Kinney, Yu-Qiu Jiang, Daniel K. Lee, Qiwen Wu, Daehoon Lee, Wen-Cheng Xiong, Qian Sun
Summary: A key mode of neuronal communication between distant brain regions is through excitatory synaptic transmission mediated by long-range glutamatergic projections. However, we found that the glutamatergic projection from the hypothalamic supramammillary nucleus (SuM) largely avoids pyramidal neurons in hippocampal CA3 region and instead targets interneurons to provide feedforward inhibition. This novel long-range glutamatergic pathway suppresses the activity of principal neurons and reveals a new means by which SuM regulates hippocampal activity.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Pharmacology & Pharmacy
Kai Zhong, Chengyu Qian, Rui Lyu, Xinyi Wang, Zhe Hu, Jie Yu, Jing Ma, Yilu Ye
Summary: Crocin has shown anti-epileptic effects in models of temporal lobe epilepsy, reducing seizure stages and duration, as well as suppressing generalized and spontaneous recurrent seizures. These effects may be mediated by its neuroprotective properties and modulation of inflammatory and neurotrophic factors.
FRONTIERS IN PHARMACOLOGY
(2022)
Review
Neurosciences
Candi L. LaSarge, Raymund Y. K. Pun, Zhiqing Gu, Matthew R. Riccetti, Devi V. Namboodiri, Durgesh Tiwari, Christina Gross, Steve C. Danzer
Summary: Mutations in genes regulating mTOR pathway signaling are recognized as a significant cause of epilepsy, often caused by somatic mutations affecting variable numbers of neurons. Deleting Pten from hippocampal granule cells can lead to seizures of varying severity, demonstrating that knockout cell load is a critical variable regulating disease phenotype.
PROGRESS IN NEUROBIOLOGY
(2021)
Article
Multidisciplinary Sciences
Can Dong, Antoine D. Madar, Mark E. J. Sheffield
Summary: The study found that CA1 and CA3 play different roles in spatial memory processing. Place fields in CA1 emerge rapidly but tend to shift backwards from trial-to-trial and remap upon re-exposure to the environment a day later, while place fields in CA3 develop gradually and show more stable trial-to-trial and day-to-day dynamics, indicating distinct functional roles in representing space for each subfield.
NATURE COMMUNICATIONS
(2021)
Article
Neurosciences
Kai-Ge Ma, Hai-Bo Hu, Jin-Song Zhou, Chao Ji, Qi-Sheng Yan, Si-Ming Peng, Lan-Dong Ren, Bing-Nan Yang, Xin-Li Xiao, Yan-Bing Ma, Feng Wu, Kai-Wei Si, Xiao-Lin Wu, Jian-Xin Liu
Summary: It has been found that Gpc4 plays a crucial role in the development of mossy fiber sprouting in the hippocampus, with the mTOR pathway being essential for Gpc4-regulated MFS. Additionally, suppressing Gpc4 expression after status epilepticus has shown to attenuate spontaneous recurrent seizures, indicating that Gpc4 may be a promising target for antiepileptic studies.
EXPERIMENTAL NEUROLOGY
(2022)
Article
Cell Biology
Bilgehan Cavdaroglu, Sadia Riaz, Yuqing Shi, Fuat Balci, Rutsuko Ito
Summary: The study found that the ventral hippocampus CA3 subregion plays a critical role in regulating timing uncertainty in temporal decision-making by reducing decision threshold variability. This research suggests that vCA3 may be important in modulating decision threshold or switch closure latency variability.
Article
Cell Biology
Jhoseph Shin, Hyun-Woo Lee, Seung-Woo Jin, Inah Lee
Summary: Environmental changes can affect the formation and modification of memories, but the neural mechanisms behind this process are not well understood. In this study, hippocampal place cells were observed in a virtual reality environment, and it was found that place cells in CA3 were more tolerant of individual landmark changes compared to CA1. When visual noise was introduced, place cells in CA1 exhibited two different responses, maintaining their field locations while changing firing rates or exhibiting global remapping in response to contextual changes. In contrast, place cells in CA3 mainly showed rate remapping. These findings suggest that CA1 may simultaneously represent heterogeneous maps of the same environment when subtle visual noise induces both sensory and contextual changes.
Article
Cell Biology
Liron Sheintuch, Nitzan Geva, Daniel Deitch, Alon Rubin, Yaniv Ziv
Summary: Hippocampal subfield CA3 is known for its role in stable memory storage. This study used large-scale Ca2+ imaging in freely behaving mice to investigate the unique coding properties of CA3 and how they contribute to the stability and precision of neural coding. The results revealed that CA3 place cells have higher precision and stability, as well as stronger statistical dependence with their peers compared to CA1 place cells, indicating a cell assembly organization in CA3. Interestingly, cells with stronger peer dependence exhibited higher stability but not higher precision. These findings highlight the relationship between tuning precision, long-term stability, and peer dependence in the hippocampus.
Article
Cell Biology
Matias Mugnaini, Mariela F. Trinchero, Alejandro F. Schinder, Veronica C. Piatti, Emilio Kropff
Summary: Optogenetic activation experiments in mice reveal that young adult-born granule cells play a unique role in remodeling spatial maps in the hippocampus, while mature adult-born granule cells do not have this ability.
Article
Neurosciences
Mahmoud Rezaei, Samireh Ghafouri, Azam Asgari, Victoria Barkley, Yaghoub Fathollahi, Sareh Rostami, Amir Shojaei, Javad Mirnajafi-Zadeh
Summary: This study investigated the role of dopamine D-2-like receptors in the antiepileptogenic action of deep brain electrical stimulation (DBS). The results suggest that DBS exerts its preventive effect on epileptogenesis, at least partly, through dopamine D-2-like receptors.
CNS NEUROSCIENCE & THERAPEUTICS
(2023)
Article
Biochemistry & Molecular Biology
Heekyung Lee, Zitong Wang, Arjuna Tillekeratne, Nick Lukish, Vyash Puliyadi, Scott Zeger, Michela Gallagher, James J. Knierim
Summary: Age-related deficits in pattern separation bias hippocampal memory processing towards pattern completion. The CA3 region of the hippocampus demonstrates a functional gradient along the transverse axis, with pattern-separated outputs dominant in the proximal CA3 and pattern-completed outputs dominant in the distal CA3.
Article
Multidisciplinary Sciences
Yang Liu, Si-Long Deng, Liang-Xia Li, Zi-Xiang Zhou, Qiu Lv, Zhong-Yuan Wang, Fang Wang, Jian-Guo Chen
Summary: The preference for social novelty is important for both humans and rodents. Chronic social defeat stress reduces this preference in mice, but it can be reversed with neuronal activation.
Article
Neurosciences
Muhammad N. Arshad, Simon Oppenheimer, Jaye Jeong, Bilge Buyukdemirtas, Janice R. Naegele
Summary: GABAergic interneurons play a crucial role in regulating adult neurogenesis and their transplantation can alleviate seizures and increase synaptic inhibition in temporal lobe epilepsy. The transplantation also affects the types of progenitor cells involved in adult neurogenesis.
NEUROBIOLOGY OF DISEASE
(2022)
Article
Multidisciplinary Sciences
Kisang Eom
Summary: The hippocampus plays a crucial role in episodic memories and observing hippocampal cognitive processes like pattern completion is important. Previous studies lacked simultaneous observation of CA3 activities and entorhinal cortex activities that project to CA3, limiting pattern completion research. Furthermore, distinct concepts like pattern completion and pattern convergence were not separately considered. This study used a molecular analysis technique to compare neural ensembles in the hippocampal CA3 region and entorhinal cortex, providing evidence that suggests pattern completion in CA3 is induced by partial input from the entorhinal cortex. The use of molecular-based ensemble measurement allows simultaneous measurement of two or more brain regions, leading to insights into the cognitive functions of neural circuits.
Article
Biochemistry & Molecular Biology
Marilia da Cunha Feio Leal, Fabio Leite do Amaral, Bernardo Freire da Silva Arruda, Juliana Ayumi Azevedo Kurosawa, Amanda Almeida Vieira, Julia Correa Campos Maia, Viviana Virginia Bezerra Scalfoni, Antonio Morais da Silveira, Matheus Oliveira Feijo, Fernanda Beatriz Araujo de Albuquerque, Maria Helena Moutinho Marta, Marina Paula Nobre Normando, Alana Gabriele Oliveira Cabeca da Silva, Fernanda Catharina Pires da Trindade, Fabiola de Carvalho Chaves de Siqueira Mendes, Marcia Consentino Kronka Sosthenes
Summary: This study evaluated the effects of masticatory activity, aging, and environmental enrichment on the quantification of hippocampal astrocytes. The results showed no significant change in most layers of the hippocampus, but significant differences were observed in a specific layer associated with diet regimens and age.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)