1. |
Kensho Kanehisa, Keisuke Koga, Sho Maejima, Yuto Shiraishi, Konatsu Asai, Miho Shiratori-Hayashi, Mei-Fang Xiao, Hirotaka Sakamoto, Paul F Worley, Makoto Tsuda, Neuronal pentraxin 2 is required for facilitating excitatory synaptic inputs onto spinal neurons involved in pruriceptive transmission in a model of chronic itch., Nature communications, 10.1038/s41467-022-30089-x, 13, 1, 2367-2367, 2022.05, An excitatory neuron subset in the spinal dorsal horn (SDH) that expresses gastrin-releasing peptide receptors (GRPR) is critical for pruriceptive transmission. Here, we show that glutamatergic excitatory inputs onto GRPR+ neurons are facilitated in mouse models of chronic itch. In these models, neuronal pentraxin 2 (NPTX2), an activity-dependent immediate early gene product, is upregulated in the dorsal root ganglion (DRG) neurons. Electron microscopy reveals that NPTX2 is present at presynaptic terminals connected onto postsynaptic GRPR+ neurons. NPTX2-knockout prevents the facilitation of synaptic inputs to GRPR+ neurons, and repetitive scratching behavior. DRG-specific NPTX2 expression rescues the impaired behavioral phenotype in NPTX2-knockout mice. Moreover, ectopic expression of a dominant-negative form of NPTX2 in DRG neurons reduces chronic itch-like behavior in mice. Our findings indicate that the upregulation of NPTX2 expression in DRG neurons contributes to the facilitation of glutamatergic inputs onto GRPR+ neurons under chronic itch-like conditions, providing a potential therapeutic target.. |
2. |
Keita Kohno, Ryoji Shirasaka, Kohei Yoshihara, Satsuki Mikuriya, Kaori Tanaka, Keiko Takanami, Kazuhide Inoue, Hirotaka Sakamoto, Yasuyuki Ohkawa, Takahiro Masuda, Makoto Tsuda, A spinal microglia population involved in remitting and relapsing neuropathic pain., Science (New York, N.Y.), 10.1126/science.abf6805, 376, 6588, 86-90, 2022.04, Neuropathic pain is often caused by injury and diseases that affect the somatosensory system. Although pain development has been well studied, pain recovery mechanisms remain largely unknown. Here, we found that CD11c-expressing spinal microglia appear after the development of behavioral pain hypersensitivity following nerve injury. Nerve-injured mice with spinal CD11c+ microglial depletion failed to recover spontaneously from this hypersensitivity. CD11c+ microglia expressed insulin-like growth factor-1 (IGF1), and interference with IGF1 signaling recapitulated the impairment in pain recovery. In pain-recovered mice, the depletion of CD11c+ microglia or the interruption of IGF1 signaling resulted in a relapse in pain hypersensitivity. Our findings reveal a mechanism for the remission and recurrence of neuropathic pain, providing potential targets for therapeutic strategies.. |
3. |
Ryoichi Tashima, Keisuke Koga, Yu Yoshikawa, Misuzu Sekine, Moeka Watanabe, Hidetoshi Tozaki-Saitoh, Hidemasa Furue, Toshiharu Yasaka, Makoto Tsuda, A subset of spinal dorsal horn interneurons crucial for gating touch-evoked pain-like behavior., Proceedings of the National Academy of Sciences of the United States of America, 10.1073/pnas.2021220118, 118, 3, 2021.01, A cardinal, intractable symptom of neuropathic pain is mechanical allodynia, pain caused by innocuous stimuli via low-threshold mechanoreceptors such as Aβ fibers. However, the mechanism by which Aβ fiber-derived signals are converted to pain remains incompletely understood. Here we identify a subset of inhibitory interneurons in the spinal dorsal horn (SDH) operated by adeno-associated viral vectors incorporating a neuropeptide Y promoter (AAV-NpyP+) and show that specific ablation or silencing of AAV-NpyP+ SDH interneurons converted touch-sensing Aβ fiber-derived signals to morphine-resistant pain-like behavioral responses. AAV-NpyP+ neurons received excitatory inputs from Aβ fibers and transmitted inhibitory GABA signals to lamina I neurons projecting to the brain. In a model of neuropathic pain developed by peripheral nerve injury, AAV-NpyP+ neurons exhibited deeper resting membrane potentials, and their excitation by Aβ fibers was impaired. Conversely, chemogenetic activation of AAV-NpyP+ neurons in nerve-injured rats reversed Aβ fiber-derived neuropathic pain-like behavior that was shown to be morphine-resistant and reduced pathological neuronal activation of superficial SDH including lamina I. These findings suggest that identified inhibitory SDH interneurons that act as a critical brake on conversion of touch-sensing Aβ fiber signals into pain-like behavioral responses. Thus, enhancing activity of these neurons may offer a novel strategy for treating neuropathic allodynia.. |
4. |
Yuta Kohro, Tsuyoshi Matsuda, Kohei Yoshihara, Keita Kohno, Keisuke Koga, Ryuichi Katsuragi, Takaaki Oka, Ryoichi Tashima, Sho Muneta, Takuya Yamane, Shota Okada, Kazuya Momokino, Aogu Furusho, Kenji Hamase, Takumi Oti, Hirotaka Sakamoto, Kenichiro Hayashida, Ryosuke Kobayashi, Takuro Horii, Izuho Hatada, Hidetoshi Tozaki-Saitoh, Katsuhiko Mikoshiba, Verdon Taylor, Kazuhide Inoue, Makoto Tsuda, Spinal astrocytes in superficial laminae gate brainstem descending control of mechanosensory hypersensitivity., Nature neuroscience, 10.1038/s41593-020-00713-4, 23, 11, 1376-1387, 2020.11, Astrocytes are critical regulators of CNS function and are proposed to be heterogeneous in the developing brain and spinal cord. Here we identify a population of astrocytes located in the superficial laminae of the spinal dorsal horn (SDH) in adults that is genetically defined by Hes5. In vivo imaging revealed that noxious stimulation by intraplantar capsaicin injection activated Hes5+ SDH astrocytes via α1A-adrenoceptors (α1A-ARs) through descending noradrenergic signaling from the locus coeruleus. Intrathecal norepinephrine induced mechanical pain hypersensitivity via α1A-ARs in Hes5+ astrocytes, and chemogenetic stimulation of Hes5+ SDH astrocytes was sufficient to produce the hypersensitivity. Furthermore, capsaicin-induced mechanical hypersensitivity was prevented by the inhibition of descending locus coeruleus-noradrenergic signaling onto Hes5+ astrocytes. Moreover, in a model of chronic pain, α1A-ARs in Hes5+ astrocytes were critical regulators for determining an analgesic effect of duloxetine. Our findings identify a superficial SDH-selective astrocyte population that gates descending noradrenergic control of mechanosensory behavior.. |
5. |
Keisuke Koga, Ryo Yamagata, Keita Kohno, Takuya Yamane, Miho Shiratori-Hayashi, Yuta Kohro, Hidetoshi Tozaki-Saitoh, Makoto Tsuda, Sensitization of spinal itch transmission neurons in a mouse model of chronic itch requires an astrocytic factor, Journal of Allergy and Clinical Immunology, 10.1016/j.jaci.2019.09.034, 145, 1, 183-191.e10, 2020.01, Background: Chronic itch is a highly debilitating symptom among patients with inflammatory skin diseases. Recent studies have revealed that gastrin-releasing peptide (GRP) and its receptor (gastrin-releasing peptide receptor [GRPR]) in the spinal dorsal horn (SDH) play a central role in itch transmission. Objective: We aimed to investigate whether GRP-GRPR signaling is altered in SDH neurons in a mouse model of chronic itch and to determine the potential mechanisms underlying these alterations. Methods: Patch-clamp recordings from enhanced green fluorescent protein (EGFP)–expressing (GRPR+) SDH neurons were used to examine GRP-GRPR signaling in spinal cord slices obtained from Grpr-EGFP mice. Immunohistochemical, genetic (gene expression and editing through adeno-associated virus vectors), and behavioral approaches were also used for in vivo experiments. Results: We observed potentiation of GRP-evoked excitation in the GRPR+ SDH neurons of mice with contact dermatitis, without concomitant changes in GRPR expression. Interestingly, increases in excitation were attenuated by suppressing the reactive state of SDH astrocytes, which are known to be reactive in patients with chronic itch conditions. Furthermore, CRISPR-Cas9–mediated astrocyte-selective in vivo editing of a gene encoding lipocalin-2 (LCN2), an astrocytic factor implicated in chronic itch, suppressed increases in GRP-induced excitation of GRPR+ neurons, repetitive scratching, and skin damage in mice with contact dermatitis. Moreover, LCN2 potentiated GRP-induced excitation of GRPR+ neurons in normal mice. Conclusion: Our findings indicate that, under chronic itch conditions, the GRP-induced excitability of GRPR+ SDH neurons is enhanced through a non–cell-autonomous mechanism involving LCN2 derived from reactive astrocytes.. |
6. |
Keisuke Koga, Ryo Yamagata, Keita Kohno, Takuya Yamane, Miho Shiratori-Hayashi, Yuta Kohro, Hidetoshi Tozaki-Saitoh, Makoto Tsuda, Sensitization of spinal itch transmission neurons in a mouse model of chronic itch requires an astrocytic factor., The Journal of allergy and clinical immunology, 10.1016/j.jaci.2019.09.034, 145, 1, 183-191, 2020.01, BACKGROUND: Chronic itch is a highly debilitating symptom among patients with inflammatory skin diseases. Recent studies have revealed that gastrin-releasing peptide (GRP) and its receptor (gastrin-releasing peptide receptor [GRPR]) in the spinal dorsal horn (SDH) play a central role in itch transmission. OBJECTIVE: We aimed to investigate whether GRP-GRPR signaling is altered in SDH neurons in a mouse model of chronic itch and to determine the potential mechanisms underlying these alterations. METHODS: Patch-clamp recordings from enhanced green fluorescent protein (EGFP)-expressing (GRPR+) SDH neurons were used to examine GRP-GRPR signaling in spinal cord slices obtained from Grpr-EGFP mice. Immunohistochemical, genetic (gene expression and editing through adeno-associated virus vectors), and behavioral approaches were also used for in vivo experiments. RESULTS: We observed potentiation of GRP-evoked excitation in the GRPR+ SDH neurons of mice with contact dermatitis, without concomitant changes in GRPR expression. Interestingly, increases in excitation were attenuated by suppressing the reactive state of SDH astrocytes, which are known to be reactive in patients with chronic itch conditions. Furthermore, CRISPR-Cas9-mediated astrocyte-selective in vivo editing of a gene encoding lipocalin-2 (LCN2), an astrocytic factor implicated in chronic itch, suppressed increases in GRP-induced excitation of GRPR+ neurons, repetitive scratching, and skin damage in mice with contact dermatitis. Moreover, LCN2 potentiated GRP-induced excitation of GRPR+ neurons in normal mice. CONCLUSION: Our findings indicate that, under chronic itch conditions, the GRP-induced excitability of GRPR+ SDH neurons is enhanced through a non-cell-autonomous mechanism involving LCN2 derived from reactive astrocytes.. |
7. |
Tashima R, Koga K, Sekine M, Kanehisa K, Kohro Y, Tominaga K, Matsushita K, Tozaki-Saitoh H, Fukazawa Y, Inoue K, Yawo H, Furue H, Tsuda M, Optogenetic activation of non-nociceptive Aβ fibers induces neuropathic pain-like sensory and emotional behaviors after nerve injury in rats., eNeuro, 10.1523/ENEURO.0450-17.2018, 5, ENEURO.0450-17.2018, 2018.02. |
8. |
Masuda T et al., Dorsal horn neurons release extracellular ATP in a VNUT-dependent manner that underlies neuropathic pain, Nat Commun, 7, 12529, 2016.08. |
9. |
Tashima R et al., Bone marrow-derived cells in the population of spinal microglia after peripheral nerve injury, Sci Rep, 6, 23701, 2016.03. |
10. |
Yuta Kohro et al., A new minimally-invasive method for microinjection into the mouse spinal dorsal horn, Sci Rep, 5, 14306, 2015.09. |
11. |
Miho Shiatori-Hayashi et al., STAT3-dependent reactive astrogliosis in the spinal dorsal horn underlies chronic itch, NATURE MEDICINE, 10.1038/nm.3912, 21, 8, 927-931, 2015.08, Chronic itch is an intractable symptom of inflammatory skin diseases, such as atopic and contact dermatitis. Recent studies have revealed neuronal pathways selective for itch, but the mechanisms by which itch turns into a pathological chronic state are poorly understood. Using mouse models of atopic and contact dermatitis, we demonstrate a long-term reactive state of astrocytes in the dorsal horn of the spinal segments that corresponds to lesioned, itchy skin. We found that reactive astrogliosis depended on the activation of signal transducer and activator of transcription 3 (STAT3). Conditional disruption of astrocytic STAT3 suppressed chronic itch, and pharmacological inhibition of spinal STAT3 ameliorated the fully developed chronic itch. Mice with atopic dermatitis exhibited an increase in scratching elicited by intrathecal administration of the itch-inducer gastrin-releasing peptide (GRP), and this enhancement was normalized by suppressing STAT3-mediated reactive astrogliosis. Moreover, we identified lipocalin-2 (LCN2) as an astrocytic STAT3-dependent upregulated factor that was crucial for chronic itch, and we demonstrated that intrathecal administration of LCN2 to normal mice increased spinal GRP-evoked scratching. Our findings indicate that STAT3-dependent reactive astrocytes act as critical amplifiers of itching through a mechanism involving the enhancement of spinal itch signals by LCN2, thereby providing a previously unrecognized target for treating chronic itch.. |
12. |
Matsushita K et al., Chemokine (C-C motif) receptor 5 is an important pathological regulator in the development and maintenance of neuropathic pain., Anesthesiology, 120, 6, 1491-1503, 2014.06. |
13. |
Masuda Takahiro et al., Transcription factor IRF5 drives P2X4R+-reactive microglia gating neuropathic pain., Nat Commun, 5, 3771, 2014.05, 神経のダメージで発症する慢性的な痛み(神経障害性疼痛)の原因タンパク質として「IRF5」を突き止めました。IRF5は、神経の損傷後に脳・脊髄の免疫細胞であるミクログリアで増え、IRF5欠損マウスでは痛みが弱くなっていました。さらに、2003年にP2X4受容体タンパク質のミクログリアでの増加が神経障害性疼痛に重要であることを英国科学誌Natureで発表していますが、今回見つかったIRF5がP2X4受容体を増やす実行役であることも明らかにしました。この研究成果は、慢性疼痛メカニズムの解明へ向けた大きな前進となり、痛みを緩和する治療薬の開発に応用できることが期待されます(Nature Communications誌掲載)。. |
14. |
Masuda Takahiro, TSUDA MAKOTO, Ryohei Yoshinaga, Hidetoshi Saitoh, Keiko Ozato, Tomohiko Tamura, Kazuhide Inoue, IRF8 Is a Critical Transcription Factor for Transforming Microglia into a Reactive Phenotype, CELL REPORTS, 10.1016/j.celrep.2012.02.014, 1, 4, 334-340, 2012.04, 神経のダメージで発症する慢性的な激しい痛み(神経障害性疼痛)の原因タンパク質として「IRF8」を突き止めました。神経の損傷後,IRF8は脳・脊髄の免疫細胞と呼ばれる「ミクログリア」だけで劇的に増えており,同細胞の過度な活性化状態をつくりだして激しい痛みを引き起こすことを明らかにしました。また,IRF8は中枢神経においてミクログリア特異的に発現する転写因子として世界初の例であり,他の神経疾患においてもミクログリアの活性化が報告されていることから,他の領域にも本成果が波及することが期待できる。この研究成果は,慢性疼痛メカニズムの解明へ向けた大きな前進となり,痛みを緩和する治療薬の開発に応用できることが期待されます(Cell Reports誌掲載)。. |
15. |
Biber K*, Tsuda M*, Tozaki-Saitoh H*, Tsukamoto K, Toyomitsu E, Masuda T, Boddeke H, Inoue K. (*equal contributors), Neuronal CCL21 up-regulates microglia P2X4 expression and initiates neuropathic pain development., EMBO J, 30, 9, 1864-1873, 2011.05. |
16. |
Tsuda M, Kohro Y, Yano T, Tsujikawa T, Kitano J, Tozaki-Saitoh H, Koyanagi S, Ohdo S, Ji RR, Salter MW, Inoue K, JAK-STAT3 pathway regulates spinal astrocyte proliferation and neuropathic pain maintenance in rats., Brain, 134, 4, 1127-1139, 2011.04. |
17. |
Tsuda M, Toyomitsu E, Kometani M, Tozaki-Saitoh H, Inoue K, Mechanisms underlying fibronectin-induced up-regulation of P2X4R expression in microglia: distinct roles of PI3K-Akt and MEK-ERK signalling pathways, J Cell Mol Med, 13, 9b, 3251-9, 2009.09. |
18. |
Tsuda M, Kuboyama K, Inoue T, Nagata K, Tozaki-Saitoh H, Inoue K, Behavioral phenotypes of mice lacking purinergic P2X4 receptors in acute and chronic pain assays, Mol Pain, 5, 28, 2009.06. |
19. |
Tsuda M, Masuda T, Kitano J, Shimoyama H, Tozaki-Saitoh H, Inoue K, IFN-gamma receptor signaling mediates spinal microglia activation driving neuropathic pain, Proc Natl Acad Sci U S A, 106, 19, 8032-8037, 2009.05. |
20. |
Shinozaki Y, Sumitomo K, Tsuda M, Koizumi S, Inoue K, Torimitsu K, Direct Observation of ATP-Induced Conformational Changes in Single P2X4 Receptors, PLoS Biol, 7, 5, e103, 2009.05. |
21. |
Tozaki-Saitoh H, Tsuda M, Miyata H, Ueda K, Kohsaka S, Inoue K, P2Y12 receptors in spinal microglia are required for neuropathic pain after peripheral nerve injury, J Neurosci 28: 4949-4956 (2008), 28: 4949-4956, 2008.05. |
22. |
Tsuda M, Toyomitsu E, Komatsu T, Masuda T, Kunifusa E, Nasu-Tada K, Koizumi S, Yamamoto K, Ando J, Inoue K, Fibronectin/integrin system is involved in P2X(4) receptor upregulation in the spinal cord and neuropathic pain after nerve injury, Glia 56: 579-585 (2008), 2008.04. |
23. |
Tsuda M, Ueno H, Kataoka A, Tozaki-Saitoh H, Inoue K, Activation of dorsal horn microglia contributes to diabetes-induced tactile allodynia via extracellular signal-regulated protein kinase signaling, Glia 56: 378-386 (2008), 2008.03. |
24. |
Lyn tyrosine kinase is required for P2X4 receptor upregulation and neuropathic pain after peripheral nerve injury, Tsuda M, Tozaki-Saitoh H, Masuda T, Toyomitsu E, Tezuka T, Yamamoto T, Inoue K, Glia 56: 50-58 (2008), 2008.01. |
25. |
Tsuda M, Hasegawa S, Inoue K, P2X receptors-mediated cytosolic phospholipase A2 activation in primary afferent sensory neurons contributes to neuropathic pain, J Neurochem 103: 1408-1416 (2007), 2007.11. |
26. |
Koizumi S, Shigemoto-Mogami Y, Nasu-Tada K, Shinozaki Y, Ohsawa K, Tsuda M, Joshi BV, Jacobson KA, Kohsaka S, Inoue K., UDP acting at P2Y(6) receptors is a mediator of microglial phagocytosis., Nature. 446: 1091-1095 (2007), 2007.04. |
27. |
Nasu-Tada K, Koizumi S, Tsuda M, Kunifusa E, Inoue K., Possible involvement of increase in spinal fibronectin following peripheral nerve injury in upregulation of microglial P2X4, a key molecule for mechanical allodynia., Glia. 2006 May;53(7):769-75., 2006.05. |
28. |
Coull JA, Beggs S, Boudreau D, Boivin D, Tsuda M, Inoue K, Gravel C, Salter MW, De Koninck Y., BDNF from microglia causes the shift in neuronal anion gradient underlying neuropathic pain., Nature. 2005 Dec 15;438(7070):1017-21. , 10.1038/nature04223, 438, 7070, 1017-1021, 2005.12. |
29. |
Tsuda M, Mizokoshi A, Shigemoto-Mogami Y, Koizumi S, Inoue K., Activation of p38 mitogen-activated protein kinase in spinal hyperactive microglia contributes to pain hypersensitivity following peripheral nerve injury., Glia. 2004 Jan 1;45(1):89-95., 10.1002/glia.10308, 45, 1, 89-95, 2004.01. |
30. |
Tsuda M, Shigemoto-Mogami Y, Koizumi S, Mizokoshi A, Kohsaka S, Salter MW, Inoue K. Related Articles, Links , P2X4 receptors induced in spinal microglia gate tactile allodynia after nerve injury., Nature. 2003 Aug 14;424(6950):778-83., 10.1038/nature01786, 424, 6950, 778-783, 2003.08. |
31. |
Tsuda M, Koizumi S, Kita A, Shigemoto Y, Ueno S, Inoue K., Mechanical allodynia caused by intraplantar injection of P2X receptor agonist in rats: involvement of heteromeric P2X2/3 receptor signaling in capsaicin-insensitive primary afferent neurons., J Neurosci. 2000 Aug 1;20(15):RC90., 20, 15, 2000.08. |