Elevated prelimbic cortex-to-basolateral amygdala circuit activity mediates comorbid anxiety-like behaviors in chronic pain

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Abstract

Chronic pain could cause both hyperalgesia and anxiety symptoms. How the two components are encoded in the brain remains unclear. The prelimbic cortex (PrL), a critical brain region for both nociceptive and emotional modulations, serves as an ideal medium for comparing the encoding of the two components. We report that PrL neurons projecting to the basolateral amygdala (PrLBLA) and those projecting to the ventrolateral periaqueductal gray (PrLl/vlPAG) were segregated and displayed elevated and reduced neuronal activity, respectively, during pain chronicity. Consistently, optogenetic suppression of PrL→BLA circuit reversed anxiety-like behaviors whereas activation of PrL→l/vlPAG circuit attenuated hyperalgesia in mice with chronic pain. Moreover, mechanistic studies indicated that elevated TNF-α/TNFR1 signaling in PrL caused increased insertion of GluA1 receptors into PrLBLA neurons contributing to anxiety-like behaviors in mice with chronic pain. Together, these results provide insights into the circuit and molecular mechanisms in PrL for controlling pain-related hyperalgesia and anxiety-like behaviors.

Authors

Feng Gao, Jie Huang, Guo-Bin Huang, Qiang-Long You, Shan Yao, Shen-Ting Zhao, Jian Liu, Cui-Hong Wu, Gui-Fu Chen, Shi-Min Liu, Zongyan Yu, Yan-Ling Zhou, Yu-Ping Ning, Shenquan Liu, Bing-Jie Hu, Xiang-Dong Sun

Monoclonal antibody Y01 prevents tauopathy progression induced by lysine280-acetylated tau in cell and mouse models

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Abstract

The spatiotemporal pattern of the spread of pathologically modified tau through brain regions in Alzheimer’s disease (AD) can be explained by prion-like cell-to-cell seeding and propagation of misfolded tau aggregates. Hence, to develop targeted therapeutic antibodies, it is important to identify the seeding- and propagation-competent tau species. The hexapeptide 275VQIINK280 of tau is a critical region for tau aggregation, and K280 is acetylated in various tauopathies including AD. However, the mechanism that links tau acetylated on lysine 280 (tau-acK280) to subsequent progression to neurodegenerative disease remains unclear. Here, we demonstrate that tau-acK280 is critical for tau propagation processes including secretion, aggregation, and seeding. We developed an antibody, Y01, that specifically targets tau-acK280 and solved the crystal structure of Y01 in complex with an acK280 peptide. The structure confirmed that Y01 directly recognizes acK280 and the surrounding residues. Strikingly, upon interaction with acetylated tau aggregates, Y01 prevented tauopathy progression and increased neuronal viability in neuron cultures and in tau transgenic mice through antibody-mediated neutralization and phagocytosis, respectively. Based on our observations that tau-acK280 is a core species involved in seeding and propagation activities, the Y01 antibody that specifically recognizes acK280 represents a promising therapeutic candidate for AD and other neurodegenerative diseases associated with tauopathy.

Authors

Ha-Lim Song, Na-Young Kim, Jaewan Park, Meong Il Kim, Yu-Na Jeon, Se-Jong Lee, Kwangmin Cho, Young-Lim Shim, Kyoung-Hye Lee, Yeon-Seon Mun, Jung-A Song, Min-Seok Kim, Chan-Gi Pack, Minkyo Jung, Hyemin Jang, Duk L. Na, Minsun Hong, Dong-Hou Kim, Seung-Yong Yoon

Chronic pain and premature mortality in men and women, using data from UK Biobank. Reply.

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Abstract

Authors

Marc Parisien, Audrey V. Grant, Arjun Muralidharan, Luda Diatchenko, Jeffrey S. Mogil

O-GlcNAc transferase in astrocytes modulates depression-related stress susceptibility through glutamatergic synaptic transmission

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Abstract

Major depressive disorder is a common and devastating psychiatric disease, the prevalence and burden are substantially increasing worldwide. Multiple studies of depression patients have implicated glucose metabolic dysfunction in the pathophysiology of depression. However, the molecular mechanisms by which glucose and related metabolic pathways modulate depressive-like behaviors are largely uncharacterized. UDP-GlcNAc is a glucose metabolite with pivotal functions as a donor molecule for O-GlcNAcylation. O-GlcNAc transferase (OGT), a key enzyme in protein O-GlcNAcylation, catalyzes protein posttranslational modification by O-GlcNAc and acts as a stress sensor. Here, we show that Ogt mRNA was increased in depression patients and that astroglial OGT expression was specifically upregulated in the medial prefrontal cortex of susceptible mice after chronic social defeat stress. The selective deletion of astrocytic OGT resulted in antidepressant-like behaviors, moreover, astrocytic OGT in the mPFC bidirectionally regulated vulnerability to social stress. Furthermore, OGT modulated glutamatergic synaptic transmission through O-GlcNAcylation of glutamate transporter-1 (GLT-1) in astrocytes. OGT astrocyte-specific knockout preserved the neuronal morphology atrophy and Ca2+ activity deficits caused by chronic stress and resulted in antidepressant effects. Altogether, our study reveals that astrocytic OGT in the mPFC regulates depressive-like behaviors through the O-GlcNAcylation of GLT-1 and could be a potential target for antidepressants.

Authors

Jun Fan, Fang Guo, Ran Mo, Liang-Yu Chen, Jiawen Mo, Cheng-lin Lu, Jing Ren, Qiuling Zhong, Xiaojing Kuang, Youlu Wen, Ting-Ting Gu, Jinming Liu, Shuji Li, Yingying Fang, Cunyou Zhao, Tian-Ming Gao, Xiong Cao

Neuron-oligodendrocyte potassium shuttling at nodes of Ranvier protects against inflammatory demyelination

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Abstract

Multiple sclerosis (MS) is a progressive inflammatory-demyelinating disease of the central nervous system. Increasing evidence suggests that vulnerable neurons in MS exhibit fatal metabolic exhaustion over time, a phenomenon hypothesized to be caused by chronic hyperexcitability. Axonal Kv7 (outward rectifying) and oligodendroglial Kir4.1 (inward rectifying) potassium channels have important roles in regulating neuronal excitability at and around nodes of Ranvier. Here, we studied the spatial and functional relationship between neuronal Kv7 and oligodendroglial Kir4.1 channels and assessed the transcriptional and functional signatures of cortical and retinal projection neurons under physiological and inflammatory-demyelinating conditions. We found that both channels became dysregulated in MS and experimental autoimmune encephalomyelitis (EAE) with Kir4.1 channels being chronically downregulated and Kv7 channel subunits being transiently upregulated during inflammatory demyelination. Further, we observed that pharmacological Kv7 channel opening with retigabine reduced neuronal hyperexcitability in human and EAE neurons, improved clinical EAE signs and rescued neuronal pathology in oligodendrocyte-Kir4.1-deficient mice. In summary, our findings indicate that neuron-oligodendrocyte compensatory interactions promote resilience through Kv7 and Kir4.1 channels and suggest pharmacological activation of nodal Kv7 channels as a neuroprotective strategy against inflammatory demyelination.

Authors

Hannah Kapell, Luca Fazio, Julia Dyckow, Sophia Schwarz, Andrés Cruz-Herranz, Christina Mayer, Joaquin Campos, Elisa D´Este, Wiebke Möbius, Christian Cordano, Anne-Katrin Pröbstel, Marjan Gharagozloo, Amel Zulji, Venu Narayanan Naik, Anna-Katharina Delank, Manuela Cerina, Thomas Müntefering, Celia Lerma-Martin, Jana K. Sonner, Jung H. Sin, Paul Disse, Nicole Rychlik, Khalida Sabeur, Manideep Chavali, Rajneesh Srivastava, Matthias Heidenreich, Kathryn C. Fitzgerald, Guiscard Seebohm, Christine Stadelmann, Bernhard Hemmer, Michael Platten, Thomas J. Jentsch, Maren Engelhardt, Thomas Budde, Klaus-Armin Nave, Peter A. Calabresi, Manuel A. Friese, Ari J. Green, Claudio Acuna, David H. Rowitch, Sven G. Meuth, Lucas Schirmer

A TRPV4-dependent neuro-immune axis in the spinal cord promotes neuropathic pain

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Abstract

Microglia, resident macrophages of the central nervous system (CNS), are essential to brain development, homeostasis, and disease. Microglial activation and proliferation are hallmarks of many CNS diseases including neuropathic pain. However, molecular mechanisms that govern the spinal neuro-immune axis in the setting of neuropathic pain remain incompletely understood. Here we show that genetic ablation or pharmacological blockade of transient receptor potential vanilloid type 4 (TRPV4) markedly attenuated neuropathic pain-like behaviors in a mouse model of spared nerve injury. Mechanistically, microglia-expressed TRPV4 mediated microglial activation and proliferation and promoted functional and structural plasticity of excitatory spinal neurons through releasing lipocalin-2. Our results suggest that microglial TRPV4 channels reside at the center of the neuro-immune axis in the spinal cord that transforms peripheral nerve injury into central sensitization and neuropathic pain, thereby identifying TRPV4 as a promising new target for the treatment of chronic pain.

Authors

Xueming Hu, Lixia Du, Shenbin Liu, Zhou Lan, Kaikai Zang, Jing Feng, Yonghui Zhao, Xingliang Yang, Zili Xie, Peter L. Wang, Aaron M. Ver Heul, Lvyi Chen, Vijay K. Samineni, Yan-Qing Wang, Kory J. Lavine, Robert W. Gereau, Gregory F. Wu, Hongzhen Hu

Pre-clinical and clinical evidence for suppression of alcohol intake by apremilast

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Abstract

Treatment options for Alcohol Use Disorders (AUD) have minimally advanced since 2004, while the annual deaths and economic toll have increased alarmingly. Phosphodiesterase type 4 (PDE4) is associated with alcohol and nicotine dependence. PDE4 inhibitors were identified as a potential AUD treatment using a novel bioinformatics approach. We prioritized a newer PDE4 inhibitor, apremilast, as ideal for repurposing, (i.e. FDA approved for psoriasis, low incidence of adverse events, excellent safety profile), and tested it using multiple animal strains and models, as well as in a human Phase IIa study. We found that apremilast reduced binge-like alcohol intake and behavioral measures of alcohol motivation in mouse models of genetic risk for drinking to intoxication. Apremilast also reduced excessive alcohol drinking in models for stress-facilitated drinking and alcohol dependence. Using site-directed drug infusions and electrophysiology, we uncovered that apremilast may act to lessen drinking in mice by increasing neural activity in the nucleus accumbens, a key brain region in the regulation of alcohol intake. Importantly, apremilast (90 mg/d) reduced excessive drinking in non-treatment seeking individuals with AUD in a double blind, placebo-controlled study. These results demonstrate that apremilast suppresses excessive alcohol drinking across the spectrum of AUD severity.

Authors

Kolter B. Grigsby, Regina A. Mangieri, Amanda J. Roberts, Marcelo F. Lopez, Evan J. Firsick, Kayla G. Townsley, Alan Beneze, Jessica Bess, Toby K. Eisenstein, Joseph J. Meissler, John M. Light, Jenny Miller, Susan Quello, Farhad Shadan, Michael H. Skinner, Heather C. Aziz, Pamela Metten, Richard A. Morissett, John C. Crabbe, Marisa Roberto, Howard C. Becker, Barbara J. Mason, Angela R. Ozburn

Astroglial toxicity promotes synaptic degeneration in the thalamocortical circuit in frontotemporal dementia with GRN mutations

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Abstract

Mutations in the human Progranulin (GRN) gene are a leading cause of frontotemporal lobar degeneration (FTLD). While previous studies implicate aberrant microglial activation as a disease-driving factor in neurodegeneration in the thalamocortical circuit in Grn-/- mice, the exact mechanism for neurodegeneration in FTLD-GRN remains unclear. By performing comparative single-cell transcriptomics in the thalamus and frontal cortex of Grn-/- mice and patients with FTLD-GRN, we have uncovered a highly conserved astroglial pathology characterized by upregulation of gap junction protein GJA1, water channel AQP4, and lipid-binding protein APOE, and downregulation of glutamate transporter SLC1A2 that promoted profound synaptic degeneration across the two species. This astroglial toxicity could be recapitulated in mouse astrocyte-neuron cocultures and by transplanting induced pluripotent stem cell-derived astrocytes to cortical organoids, where Progranulin-deficient astrocytes promoted synaptic degeneration, neuronal stress, and TDP-43 proteinopathy. Together, these results reveal previously unappreciated astroglial pathology as a key mechanism in neurodegeneration in FTLD-GRN.

Authors

Elise Marsan, Dmitry Velmeshev, Arren Ramsey, Ravi K. Patel, Jiasheng Zhang, Mark Koontz, Madeline G. Andrews, Martina de Majo, Cristina Mora, Jessica Blumenfeld, Alissa N. Li, Salvatore Spina, Lea T. Grinberg, William Seeley, Bruce L. Miller, Erik M. Ullian, Matthew F. Krummel, Arnold Kriegstein, Eric J. Huang

Highly synchronized cortical circuit dynamics mediate spontaneous pain in mice

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Abstract

Cortical neural dynamics mediate information processing for the cerebral cortex, implicated in fundamental biological processes, such as vision and olfaction, in addition to neurological and psychiatric diseases. Spontaneous pain is a key feature of human neuropathic pain. Whether spontaneous pain pushes cortical network into an aberrant state, and if so, whether it can be brought back to a ‘normal’ operating range to ameliorate pain are unknown. Using a clinically relevant mouse model of neuropathic pain with spontaneous pain-like behavior, we report that orofacial spontaneous pain activated a specific area within the primary somatosensory cortex (S1), displaying synchronized neural dynamics revealed by intravital two-photon calcium imaging. This synchronization was underpinned by local GABAergic interneuron hypoactivity. Pain-induced cortical synchronization could be attenuated by manipulating local S1 networks or clinically effective pain therapies. Specifically, both chemogenetic inhibition of pain-related c-Fos-expressing neurons, and selective activation of GABAergic interneurons, significantly attenuated S1 synchronization. Clinically effective pain therapies including carbamazepine and nerve root decompression could also dampen S1 synchronization. More importantly, restoring a ‘normal’ range of neural dynamics, through attenuating pain-induced S1 synchronization, alleviated pain-like behavior. These results suggest spontaneous pain pushes S1 regional network into a synchronized state, whereas reversal of this synchronization alleviates pain.

Authors

Weihua Ding, Lukas Fischer, Qian Chen, Ziyi Li, Liuyue Yang, Zerong You, Kun Hu, Xinbo Wu, Xue Zhou, Wei Chao, Peter Hu, Tewodros Mulugeta Dagnew, Daniel M. DuBreuil, Shiyu Wang, Suyun Xia, Caroline Bao, Shengmei Zhu, Lucy Chen, Changning Wang, Brian Wainger, Peng Jin, Jianren Mao, Guoping Feng, Mark T. Harnett, Shiqian Shen

Intestinal neuropod GUCY2C regulates visceral pain

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Abstract

Visceral pain (VP) is a global problem with complex etiologies and limited therapeutic options. Guanylyl cyclase C (GUCY2C), an intestinal receptor producing cyclic GMP which regulates luminal fluid secretion, has emerged as a therapeutic target for VP. Indeed, FDA-approved GUCY2C agonists ameliorate VP in patients with chronic constipation syndromes, although analgesic mechanisms remain obscure. Here, we reveal that intestinal GUCY2C is selectively enriched in neuropod cells, a type of enteroendocrine cell that synapses with submucosal neurons in mice and humans. GUCY2CHigh neuropod cells associate with co-cultured dorsal root ganglia neurons and induce hyperexcitability, reducing the rheobase and increasing the resulting number of evoked action potentials. Conversely, the GUCY2C agonist linaclotide eliminated neuronal hyperexcitability produced by GUCY2C-sufficient, but not GUCY2C-deficient, neuropod cells, an effect independent of bulk epithelial cells or extracellular cGMP. Genetic elimination of intestinal GUCY2C amplified nociceptive signaling and VP that was comparable to chemically-induced VP but refractory to linaclotide. Importantly, eliminating GUCY2C selectively in neuropod cells also increased nociceptive signaling and VP that was refractory to linaclotide. In the context of loss of GUCY2C hormones in patients with VP, these observations suggest a specific role for neuropod GUCY2C signaling in the pathophysiology and treatment of these pain syndromes.

Authors

Joshua R. Barton, Annie K. Londregan, Tyler D. Alexander, Ariana A. Entezari, Shely Bar-Ad, Lan Cheng, Angelo C. Lepore, Adam E. Snook, Manuel Covarrubias, Scott A. Waldman