Review
Biochemistry & Molecular Biology
Angela Kecskes, Boldizsar Czeh, Miklos Kecskes
Summary: This review summarizes the role of mossy cells in healthy and overexcited hippocampus, discussing the controversy surrounding their involvement in temporal lobe epilepsy.
BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH
(2022)
Article
Neurosciences
Czarina Ramos, Stefano Lutzu, Miwako Yamasaki, Yuchio Yanagawa, Kenji Sakimura, Susumu Tomita, Masahiko Watanabe, Pablo E. Castillo
Summary: This study provides the first direct evidence of functional extrasynaptic kainate receptors (KARs) on mossy cells (MCs) in the hippocampus. These KARs are mainly located extrasynaptically and play a critical role in the activity of MCs. Increases in ambient glutamate can activate the KARs on MCs.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Multidisciplinary Sciences
Katsunori Kobayashi, Kisako Shikano, Mahomi Kuroiwa, Mio Horikawa, Wakana Ito, Akinori Nishi, Eri Segi-Nishida, Hidenori Suzuki
Summary: The activation of D(1)Rs by noradrenaline is crucial for the antidepressant effects, suggesting a potential therapeutic target for depressive disorders. Increased voluntary exercise enhances the synaptic potentiation mediated by D(1)Rs, indicating a distinct role of noradrenaline-D(1)R signaling. This pathway may play a critical role in determining the responsiveness to antidepressant drugs.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Neurosciences
Lisa N. Miller, Craig Weiss, John F. Disterhoft
Summary: The dentate gyrus plays a crucial role in the formation of associative memories and previous studies have identified populations of cells that bridge the temporal gap during trace eyeblink conditioning. In this study, single-neuron recordings were performed to investigate the functional role of different cell types in the dentate gyrus during learning. The results showed that conditioned mice exhibited changes in firing rate in granule cells, mossy cells, and interneurons, suggesting their involvement in trace associative memory. Theta power also increased during stimuli presentation and decreased over time. These findings expand our understanding of dentate gyrus function and its potential disruptions in aging and disease.
Article
Multidisciplinary Sciences
Deniz A. Madencioglu, Guersel Caliskan, Pingan Yuanxiang, Kati Rehberg, Yunus E. Demiray, Emre Kul, Alexander Engler, Hussam Hayani, Jorge R. Bergado-Acosta, Anne Kummer, Iris Mueller, Inseon Song, Alexander Dityatev, Thilo Kaehne, Michael R. Kreutz, Oliver Stork
Summary: Increased expression of the Ndr2 gene may critically contribute to the development of intellectual disabilities. Through studying transgenic mice with increased Ndr2 expression in postmigratory forebrain neurons, the consequences on brain circuitry and cognitive functions were revealed.
Article
Multidisciplinary Sciences
Ruy Gomez-Ocadiz, Massimiliano Trippa, Chun-Lei Zhang, Lorenzo Posani, Simona Cocco, Remi Monasson, Christoph Schmidt-Hieber
Summary: This study reveals a synaptic novelty signal in hippocampal granule cells, which can modulate the activity of granule cell population and facilitate the formation of novel memories. This novelty-driven switch enables flexible encoding of new memories while preserving stable retrieval of familiar ones.
NATURE COMMUNICATIONS
(2022)
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)
Review
Clinical Neurology
Carlos A. Lafourcade, Fraser T. Sparks, Angelique Bordey, Ursula Wyneken, Michael H. Mohammadi
Summary: The hippocampal formation is crucial in the development of temporal lobe epilepsy (TLE), a disease characterized by recurrent, unprovoked epileptic discharges. The hippocampal dentate gyrus (DG) acts as a filter to prevent excessive excitation and is considered critical in the progression of epileptogenesis. Endogenous cannabinoids (endocannabinoids) play a central role in regulating neuronal activity in the DG circuit. This review summarizes recent findings on the role of the DG in controlling hyperexcitability and discusses the potential therapeutic interventions using cannabinoids.
Article
Neurosciences
Wahab Imam Abdulmajeed, Kai-Yi Wang, Jei-Wei Wu, Musa Iyiola Ajibola, Irene Han-Juo Cheng, Cheng-Chang Lien
Summary: This study reveals the differential regulation of local and distant granule cell activity by mossy cells in the hippocampus, highlighting the distinct synaptic mechanisms involved. These findings provide new insights into the functional organization of hippocampal circuits.
JOURNAL OF PHYSIOLOGY-LONDON
(2022)
Article
Multidisciplinary Sciences
Paul J. Lamothe-Molina, Andreas Franzelin, Lennart Beck, Dong Li, Lea Auksutat, Tim Fieblinger, Laura Laprell, Joachim Alhbeck, Christine E. Gee, Matthias Kneussel, Andreas K. Engel, Claus C. Hilgetag, Fabio Morellini, Thomas G. Oertner
Summary: Research shows that cFos expression patterns in the mouse dentate gyrus change dramatically from day to day, suggesting that this clock-like selection mechanism may aid in encoding episodic memories.
NATURE COMMUNICATIONS
(2022)
Article
Clinical Neurology
Risa Yamazaki, Dianru Wang, Anna De Laet, Renato Maciel, Claudio Agnorelli, Sebastien Cabrera, Sebastien Arthaud, Paul-Antoine Libourel, Patrice Fort, Hyunsook Lee, Pierre-Herve Luppi
Summary: The study aimed to investigate the reactivation of neurons in the hippocampus and supramammillary nucleus during wakefulness and paradoxical sleep. The results showed different activated neurons in these regions during wakefulness and paradoxical sleep, and the activation of granule cells in the infrapyramidal blade of the DG during paradoxical sleep. Further research is needed to determine the role of these granule cells in memory reactivation during paradoxical sleep.
Article
Clinical Neurology
Risa Yamazaki, Dianru Wang, Anna De Laet, Renato Maciel, Claudio Agnorelli, Sebastien Cabrera, Sebastien Arthaud, Paul-Antoine Libourel, Patrice Fort, Hyunsook Lee, Pierre-Herve Luppi
Summary: The study aimed to determine whether the same neurons were reactivated in the hippocampus and the supramammillary nucleus when mice were exposed to different periods of wakefulness and paradoxical sleep. The results showed that different neurons were activated during wakefulness and paradoxical sleep in the two brain regions, with granule cells of the infrapyramidal blade of the DG specifically activated during paradoxical sleep. Further experiments are needed to confirm if these granule cells are involved in memory engrams during paradoxical sleep.
Review
Neurosciences
Tasuku Araki, Yuji Ikegaya, Ryuta Koyama
Summary: Hippocampal neurogenesis continues throughout life and is tightly controlled by environmental conditions, with microglia and astrocytes playing key roles in modulating the process. Glial cells release factors that support adult neurogenesis under normal conditions, but can also contribute to inflammation and hinder neurogenesis in diseases like Alzheimer's, depression, and epilepsy.
EUROPEAN JOURNAL OF NEUROSCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Felipe Fredes, Maria Alejandra Silva, Peter Koppensteiner, Kenta Kobayashi, Maximilian Joesch, Ryuichi Shigemoto
Summary: The study demonstrates the important role of a pathway between ventral mossy cells and dorsal granule cells in the hippocampus in the formation of novelty-induced memory, influencing the activation of dorsal granule cells through excitatory transmission; furthermore, the manipulation of ventral mossy cell activity can bidirectionally regulate the acquisition of novelty-induced contextual memory.
Article
Neurosciences
Raenier V. Reyes, Keiko Hino, Cesar Patricio Canales, Eamonn James Dickson, Anna La Torre, Sergi Simo
Summary: This study reveals the crucial role of CRL5 in the development and adult neurogenesis of the dentate gyrus (DG) in mice. Knocking out CRL5 leads to deficient mossy fiber pruning, abnormal DG layering, disrupted neural progenitor localization, and increased adult neurogenesis. These findings have significant implications for understanding DG development and homeostasis.
FRONTIERS IN NEUROSCIENCE
(2022)
Article
Neurosciences
Ken Matsuura, Shizuka Kobayashi, Kohtarou Konno, Miwako Yamasaki, Takahiro Horiuchi, Takao Senda, Tomoatsu Hayashi, Kiyotoshi Satoh, Fumiko Arima-Yoshida, Kei Iwasaki, Lumi Negishi, Naomi Yasui-Shimizu, Kazuyoshi Kohu, Shigenori Kawahara, Yutaka Kirino, Tsutomu Nakamura, Masahiko Watanabe, Tadashi Yamamoto, Toshiya Manabe, Tetsu Akiyama
Summary: The study reveals that SIPA1L1 is mainly localized to submembranous regions in neurons, and its deficiency may be associated with neuropsychiatric disorders related to dysregulated GPCR signaling.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Neurosciences
Czarina Ramos, Stefano Lutzu, Miwako Yamasaki, Yuchio Yanagawa, Kenji Sakimura, Susumu Tomita, Masahiko Watanabe, Pablo E. Castillo
Summary: This study provides the first direct evidence of functional extrasynaptic kainate receptors (KARs) on mossy cells (MCs) in the hippocampus. These KARs are mainly located extrasynaptically and play a critical role in the activity of MCs. Increases in ambient glutamate can activate the KARs on MCs.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Cell & Tissue Engineering
Yuka Kasahara, Daiki Masukawa, Kenta Kobayashi, Miwako Yamasaki, Masahiko Watanabe, Yoshio Goshima
Summary: Neurogenesis in the hippocampus is regulated by L-DOPA and its receptor GPR143 independently of dopamine. Low concentrations of L-DOPA promote neurogenesis, and its effect is abolished in GPR143 gene-deficient mice. Decreased neurogenesis and exacerbated depression-like behavior are observed in adult GPR143 gene-deficient mice, but can be attenuated by replenishment of GPR143 in the hippocampus.
Article
Rheumatology
Nobuya Abe, Masato Tarumi, Yuichiro Fujieda, Nobuhiko Takahashi, Kohei Karino, Mona Uchida, Michihito Kono, Yuki Tanaka, Rie Hasebe, Masaru Kato, Olga Amengual, Yoshiyuki Arinuma, Kenji Oku, Wakiro Sato, Khin Khin Tha, Miwako Yamasaki, Masahiko Watanabe, Tatsuya Atsumi, Masaaki Murakami
Summary: The study investigates the effects of stress on the pathophysiology of neuropsychiatric lupus (NPSLE) in systemic lupus erythematosus (SLE) using lupus-prone mice and patient data.
ANNALS OF THE RHEUMATIC DISEASES
(2022)
Article
Biology
Amy Cheung, Kotaro Konno, Yuka Imamura, Aya Matsui, Manabu Abe, Kenji Sakimura, Toshikuni Sasaoka, Takeshi Uemura, Masahiko Watanabe, Kensuke Futai, Nils Brose
Summary: The study reveals the involvement of Nrxn genes in the modulation of 5-HT transmission and behavior, suggesting a potential link between Nrxn mutations and ASD.
Article
Neurosciences
Adrian J. Duszkiewicz, Janine I. Rossato, Andrea Moreno, Tomonori Takeuchi, Miwako Yamasaki, Lisa Genzel, Patrick Spooner, Santiago Canals, Richard G. M. Morris
Summary: The hippocampus plays a critical role in mammalian spatial navigation, with its firing sequences during sleep or immobility representing past trajectories. A recent study showed that these sequences can also map onto new paths to a goal. However, inactivating the dorsal and intermediate hippocampus had minimal effects on the same spatial navigation task, raising doubts about the causal role of prospective replay sequences. Findings from a watermaze task indicate that muscimol-induced inactivation severely impaired hippocampal-dependent episodic-like spatial memory.
Article
Neurosciences
Mahendra Singh, Kiran Sapkota, Kenji Sakimura, Masanobu Kano, Rita M. Cowell, Linda Overstreet-Wadiche, John J. Hablitz, Kazu Nakazawa
Summary: Hypofunction of the NMDAR receptor during brain development may contribute to the onset of schizophrenia in young adults. The cellular targets of NMDAR hypofunction include corticolimbic fast-spiking interneurons. However, the functional alterations in PV-positive FS interneurons following NMDAR hypofunction are not well understood.
Article
Neurosciences
Yuto Okuno, Kazuto Sakoori, Kyoko Matsuyama, Miwako Yamasaki, Masahiko Watanabe, Kouichi Hashimoto, Takaki Watanabe, Masanobu Kano
Summary: Functionally mature neural circuits are shaped by eliminating redundant synapses during postnatal development. A synapse organizer, PTPd, is necessary for CF synapse formation and establishing CF to PC synaptic wiring. PTPd KO mice showed impaired CF translocation and synaptic transmission in Aldoc (-) PCs. The lack of PTPd also caused a mild impairment of motor performance.
FRONTIERS IN MOLECULAR NEUROSCIENCE
(2023)
Article
Multidisciplinary Sciences
Kisho Obi-Nagata, Norimitsu Suzuki, Ryuhei Miyake, Matthew L. MacDonald, Kenneth N. Fish, Katsuya Ozawa, Kenichiro Nagahama, Tsukasa Okimura, Shoji Tanaka, Masanobu Kano, Yugo Fukazawa, Robert A. Sweet, Akiko Hayashi-Takagi
Summary: By studying mouse models with knockdown of the SETD1A and DISC1 genes, it was found that XL synapses can lead to excessive neuronal firing and impair working memory. This finding provides new evidence for understanding the synaptic pathology of psychiatric disorders.
Article
Biology
Kieran A. Boyle, Erika Polgar, Maria Gutierrez-Mecinas, Allen C. Dickie, Andrew H. Cooper, Andrew M. Bell, Evelline Jumolea, Adrian Casas-Benito, Masahiko Watanabe, David I. Hughes, Gregory A. Weir, John S. Riddell, Andrew J. Todd
Summary: This study investigates the role of interneurons that continue to express neuropeptide Y (NPY-INs) in the adult mouse spinal cord. The findings suggest that activation of NPY-INs reduces acute pain and pruritogen-evoked itch, while silencing them causes exaggerated itch responses. Silencing another population of inhibitory interneurons also increases itch, but to a lesser extent.
Article
Multidisciplinary Sciences
Kohtarou Konno, Miwako Yamasaki, Taisuke Miyazaki, Masahiko Watanabe
Summary: The gold-standard fixative for immunohistochemistry is 4% formaldehyde; however, it limits antibody access to buried target molecules. To solve this problem, we used glyoxal as a fixative, which greatly improved antibody penetration, uncovering signals for buried molecules. Glyoxal also enhanced immunosignals of most other molecules, including the controversial synaptic adhesion molecule Neuroligin 1.
Article
Biochemical Research Methods
Masayuki Sakamoto, Masatoshi Inoue, Atsuya Takeuchi, Shigetaka Kobari, Tatsushi Yokoyama, Shin-ichiro Horigane, Sayaka Takemoto-Kimura, Manabu Abe, Kenji Sakimura, Masanobu Kano, Kazuo Kitamura, Hajime Fujii, Haruhiko Bito
Summary: This study generates a transgenic mouse line that expresses a highly sensitive green GECI in specific neuronal populations. In vivo imaging reveals calcium transients in both excitatory and inhibitory neurons, providing a tool for investigating neuronal activity with enhanced resolution.
CELL REPORTS METHODS
(2022)