Biological Psychiatry Global Open Science
Funayama, Y;Li, H;Ishimori, E;Kawatake-Kuno, A;Inaba, H;Yamagata, H;Seki, T;Nakagawa, S;Watanabe, Y;Murai, T;Oishi, N;Uchida, S;
| DOI: 10.1016/j.bpsgos.2021.12.009
Background A key challenge in the understanding and treatment of depression is identifying cell types and molecular mechanisms that mediate behavioral responses to antidepressant drugs. As treatment responses in clinical depression are heterogeneous, it is crucial to examine treatment responders and nonresponders in preclinical studies. Methods We utilized the large variance in behavioral responses to chronic treatment with multiple class of antidepressant drugs in different inbred mouse strains and classified the mice into responders and nonresponders based on their response in the forced swim test. Medial prefrontal cortex tissues were subjected to RNA sequencing to identify molecules that are consistently associated across antidepressant responders. We developed and employed virus-mediated gene transfer to induce the gene of interest in specific cell types and performed forced swim test, sucrose preference, social interaction, and open field tests to investigate antidepressant-like and anxiety behaviors. Results Cocaine- and amphetamine-regulated transcript peptide (Cartpt) expression was consistently upregulated in responders to four types of antidepressants but not in nonresponders in different mice strains. Responder mice given a single dose of ketamine, a fast-acting non-monoamine-based antidepressant, exhibited high CART peptide expression. CART peptide overexpression in the GABAergic neurons of the anterior cingulate cortex (aCC) led to antidepressant-like behavior and drove chronic stress resiliency independently of mouse genetic background. Conclusions These data demonstrate that activation of CART peptide signaling in GABAergic neurons of the aCC is a common molecular mechanism across antidepressant responders and that this pathway also drives stress resilience.
Severino A, Chen W, Hakimian JK, Kieffer BL, Gaveriaux-Ruff C, Walwyn W, Marvizón JCG.
PMID: 29677019 | DOI: 10.1097/j.pain.0000000000001247
The latent sensitization model of chronic pain reveals that recovery from some types of long-term hyperalgesia is an altered state in which nociceptive sensitization persists but is suppressed by the ongoing activity of analgesic receptors such as μ-opioid receptors (MORs). To determine whether these MORs are the ones present in nociceptive afferents, we bred mice expressing Cre-recombinase under the Nav1.8 channel promoter (Nav1.8cre) with MOR-floxed mice (flMOR). These Nav1.8cre/flMOR mice had reduced MOR expression in primary afferents, as revealed by quantitative PCR, in situ hybridization, and immunofluorescence colocalization with the neuropeptide calcitonin gene-related peptide. We then studied the recovery from chronic pain of these mice and their flMOR littermates. When Nav1.8cre/flMOR mice were injected in the paw with complete Freund adjuvant they developed mechanical hyperalgesia that persisted for more than 2 months, whereas the responses of flMOR mice returned to baseline after 3 weeks. We then used the inverse agonist naltrexone to assess ongoing MOR activity. Naltrexone produced a robust reinstatement of hyperalgesia in control flMOR mice, but produced no effect in the Nav1.8/flMOR males and a weak reinstatement of hyperalgesia in Nav1.8/flMOR females. Naltrexone also reinstated swelling of the hind paw in flMOR mice and female Nav1.8cre/flMOR mice, but not male Nav1.8cre/flMOR mice. The MOR agonist DAMGO inhibited substance P release in flMOR mice but not Nav1.8cre/flMOR mice, demonstrating a loss of MOR function at the central terminals of primary afferents. We conclude that MORs in nociceptive afferents mediate an ongoing suppression of hyperalgesia to produce remission from chronic pain.
bioRxiv : the preprint server for biology
Shiers, S;Sahn, JJ;Price, TJ;
PMID: 36711529 | DOI: 10.1101/2023.01.04.522773
Mitogen activated protein kinase interacting kinases (MNK) 1 and 2 are serine/threonine protein kinases that play an important role in translation of mRNAs through their phosphorylation of the RNA 5†-cap binding protein, eukaryotic translation initiation factor (eIF) 4E. These kinases are downstream targets for mitogen activated protein kinases (MAPKs), extracellular activity regulated protein kinase (ERK) and p38. MNKs have been implicated in the sensitization of peripheral nociceptors of the dorsal root and trigeminal ganglion (DRG and TG) using transgenic mouse lines and through the use of specific inhibitors of MNK1 and MNK2. While specific knockout of the Mknk1 gene suggests that it is the key isoform for regulation of nociceptor excitability and nociceptive behaviors in mice, both MKNK1 and MKNK2 genes are expressed in the DRG and TG of mice and humans based on RNA sequencing experiments. Single cell sequencing in mice suggests that Mknk1 and Mknk2 may be expressed in different populations of nociceptors. We sought to characterize mRNA expression in human DRG and TG for both MNK1 and MNK2. Our results show that both genes are expressed by nearly all neurons in both human ganglia with expression in other cell types as well. Our findings provide evidence that MNK1 and MNK2 are expressed by human nociceptors and suggest that efforts to pharmacologically target MNKs for pain would likely be translatable due its conserved expression in both species.
The Journal of clinical investigation
Defaye, M;Iftinca, MC;Gadotti, VM;Basso, L;Abdullah, NS;Cumenal, M;Agosti, F;Hassan, A;Flynn, R;Martin, J;Soubeyre, V;Poulen, G;Lonjon, N;Vachiery-Lahaye, F;Bauchet, L;Mery, PF;Bourinet, E;Zamponi, GW;Altier, C;
PMID: 35608912 | DOI: 10.1172/JCI154317
The anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase known for its oncogenic potential and involved in the development of the peripheral and central nervous system. ALK receptor ligands, ALKAL1 and ALKAL2 were recently found to promote neuronal differentiation and survival. Here we show that inflammation or injury enhanced ALKAL2 expression in a subset of TRPV1+ sensory neurons. Notably, ALKAL2 was particularly enriched in both mice and human peptidergic nociceptors, yet weakly expressed in non peptidergic, large diameter myelinated neurons or in the brain. Using a co-culture expression system, we found that nociceptors exposed to ALKAL2 exhibited heightened excitability and neurite outgrowth. Intraplantar Complete Freund's adjuvant (CFA) or intrathecal infusion of recombinant ALKAL2 led to ALK phosphorylation in the lumbar dorsal horn of the spinal cord. Finally, depletion of ALKAL2 in dorsal root ganglia or blocking ALK with clinically available compounds Crizotinib or Lorlatinib, reversed thermal hyperalgesia and mechanical allodynia induced by inflammation or nerve injury, respectively. Overall, our work uncovers the ALKAL2-ALK signaling axis as a central regulator of nociceptor-induced sensitization. We propose that clinically approved ALK inhibitors used for Non-Small Cell Lung Cancer and neuroblastomas, could be repurposed to treat persistent pain conditions.
Elias, LJ;Succi, IK;Schaffler, MD;Foster, W;Gradwell, MA;Bohic, M;Fushiki, A;Upadhyay, A;Ejoh, LL;Schwark, R;Frazer, R;Bistis, B;Burke, JE;Saltz, V;Boyce, JE;Jhumka, A;Costa, RM;Abraira, VE;Abdus-Saboor, I;
PMID: 36693373 | DOI: 10.1016/j.cell.2022.12.034
Pleasurable touch is paramount during social behavior, including sexual encounters. However, the identity and precise role of sensory neurons that transduce sexual touch remain unknown. A population of sensory neurons labeled by developmental expression of the G protein-coupled receptor Mrgprb4 detects mechanical stimulation in mice. Here, we study the social relevance of Mrgprb4-lineage neurons and reveal that these neurons are required for sexual receptivity and sufficient to induce dopamine release in the brain. Even in social isolation, optogenetic stimulation of Mrgprb4-lineage neurons through the back skin is sufficient to induce a conditioned place preference and a striking dorsiflexion resembling the lordotic copulatory posture. In the absence of Mrgprb4-lineage neurons, female mice no longer find male mounts rewarding: sexual receptivity is supplanted by aggression and a coincident decline in dopamine release in the nucleus accumbens. Together, these findings establish that Mrgprb4-lineage neurons initiate a skin-to-brain circuit encoding the rewarding quality of social touch.
Chirila, AM;Rankin, G;Tseng, SY;Emanuel, AJ;Chavez-Martinez, CL;Zhang, D;Harvey, CD;Ginty, DD;
PMID: 36334588 | DOI: 10.1016/j.cell.2022.10.012
The encoding of touch in the spinal cord dorsal horn (DH) and its influence on tactile representations in the brain are poorly understood. Using a range of mechanical stimuli applied to the skin, large-scale in vivo electrophysiological recordings, and genetic manipulations, here we show that neurons in the mouse spinal cord DH receive convergent inputs from both low- and high-threshold mechanoreceptor subtypes and exhibit one of six functionally distinct mechanical response profiles. Genetic disruption of DH feedforward or feedback inhibitory motifs, comprised of interneurons with distinct mechanical response profiles, revealed an extensively interconnected DH network that enables dynamic, flexible tuning of postsynaptic dorsal column (PSDC) output neurons and dictates how neurons in the primary somatosensory cortex respond to touch. Thus, mechanoreceptor subtype convergence and non-linear transformations at the earliest stage of the somatosensory hierarchy shape how touch of the skin is represented in the brain.
Kim J, Pignatelli M, Xu S, Itohara S, Tonegawa S.
PMID: 27749826 | DOI: 10.1038/nn.4414
The basolateral amygdala (BLA) is a site of convergence of negative and positive stimuli and is critical for emotional behaviors and associations. However, the neural substrate for negative and positive behaviors and relationship between negative and positive representations in the basolateral amygdala are unknown. Here we identify two genetically distinct, spatially segregated populations of excitatory neurons in the mouse BLA that participate in valence-specific behaviors and are connected through mutual inhibition. These results identify a genetically defined neural circuit for the antagonistic control of emotional behaviors and memories.
Weil, T;Daly, KM;Yarur Castillo, H;Thomsen, MB;Wang, H;Mercau, ME;Hattar, S;Tejeda, H;Fernandez, DC;
PMID: 35687680 | DOI: 10.1126/sciadv.abn3567
Exposure to irregular lighting schedules leads to deficits in affective behaviors. The retino-recipient perihabenular nucleus (PHb) of the dorsal thalamus has been shown to mediate these effects in mice. However, the mechanisms of how light information is processed within the PHb remains unknown. Here, we show that the PHb contains a distinct cluster of GABAergic neurons that receive direct retinal input. These neurons are part of a larger inhibitory network composed of the thalamic reticular nucleus and zona incerta, known to modulate thalamocortical communication. In addition, PHbGABA neurons locally modulate excitatory-relay neurons, which project to limbic centers. Chronic exposure to irregular light-dark cycles alters photo-responsiveness and synaptic output of PHbGABA neurons, disrupting daily oscillations of genes associated with inhibitory and excitatory PHb signaling. Consequently, selective and chronic PHbGABA manipulation results in mood alterations that mimic those caused by irregular light exposure. Together, light-mediated disruption of PHb inhibitory networks underlies mood deficits.
Ali Marandi Ghoddousi, R;Magalong, VM;Kamitakahara, AK;Levitt, P;
PMID: 36313803 | DOI: 10.1016/j.crmeth.2022.100316
Spatial gene expression, achieved classically through in situ hybridization, is a fundamental tool for topographic phenotyping of cell types in the nervous system. Newly developed techniques allow for visualization of multiple mRNAs at single-cell resolution and greatly expand the ability to link gene expression to tissue topography, yet there are challenges in efficient quantification and analysis of these high-dimensional datasets. We have therefore developed the single-cell automated multiplex pipeline for RNA (SCAMPR), facilitating rapid and accurate segmentation of neuronal cell bodies using a dual immunohistochemistry-RNAscope protocol and quantification of low- and high-abundance mRNA signals using open-source image processing and automated segmentation tools. Proof of principle using SCAMPR focused on spatial mapping of gene expression by peripheral (vagal nodose) and central (visual cortex) neurons. The analytical effectiveness of SCAMPR is demonstrated by identifying the impact of early life stress on gene expression in vagal neuron subtypes.
Zhang, MM;Geng, AQ;Chen, K;Wang, J;Wang, P;Qiu, XT;Gu, JX;Fan, HW;Zhu, DY;Yang, SM;Chen, QY;Zhou, ZX;Fan, BY;Bai, Y;Xing, KK;Feng, JM;Wang, JD;Chen, Y;Lu, YC;Liang, Y;Cao, P;Kaang, BK;Zhuo, M;Li, YQ;Chen, T;
PMID: 35443154 | DOI: 10.1016/j.neuron.2022.03.030
Empathic pain has attracted the interest of a substantial number of researchers studying the social transfer of pain in the sociological, psychological, and neuroscience fields. However, the neural mechanism of empathic pain remains elusive. Here, we establish a long-term observational pain model in mice and find that glutamatergic projection from the insular cortex (IC) to the basolateral amygdala (BLA) is critical for the formation of observational pain. The selective activation or inhibition of the IC-BLA projection pathway strengthens or weakens the intensity of observational pain, respectively. The synaptic molecules are screened, and the upregulated synaptotagmin-2 and RIM3 are identified as key signals in controlling the increased synaptic glutamate transmission from the IC to the BLA. Together, these results reveal the molecular and synaptic mechanisms of a previously unidentified neural pathway that regulates observational pain in mice.
Schroeder, A;Pardi, MB;Keijser, J;Dalmay, T;Groisman, AI;Schuman, EM;Sprekeler, H;Letzkus, JJ;
PMID: 36610397 | DOI: 10.1016/j.neuron.2022.12.010
Top-down projections convey a family of signals encoding previous experiences and current aims to the sensory neocortex, where they converge with external bottom-up information to enable perception and memory. Whereas top-down control has been attributed to excitatory pathways, the existence, connectivity, and information content of inhibitory top-down projections remain elusive. Here, we combine synaptic two-photon calcium imaging, circuit mapping, cortex-dependent learning, and chemogenetics in mice to identify GABAergic afferents from the subthalamic zona incerta as a major source of top-down input to the neocortex. Incertocortical transmission undergoes robust plasticity during learning that improves information transfer and mediates behavioral memory. Unlike excitatory pathways, incertocortical afferents form a disinhibitory circuit that encodes learned top-down relevance in a bidirectional manner where the rapid appearance of negative responses serves as the main driver of changes in stimulus representation. Our results therefore reveal the distinctive contribution of long-range (dis)inhibitory afferents to the computational flexibility of neocortical circuits.
Li, H;Ou, J;Li, Y;Xu, N;Li, Q;Wu, P;Peng, C;Tang, YC;Chang, HC;
PMID: 35902736 | DOI: 10.1038/s42003-022-03725-x
Circadian dysregulation associates with numerous diseases including metabolic dysfunction, sleep disorder, depression and aging. Given that declined circadian amplitude is a trait commonly found with compromised health, interventions that design in precluding circadian amplitude from dampening will aid to mitigate complex, circadian-related diseases. Here we identify a neurogenic small molecule ISX-9 that is able to support persistent and higher amplitude of circadian oscillations. ISX-9 improves diurnal metabolic rhythms in middle-aged mice. Moreover, the ISX-9-treated mice show better sleep homeostasis with increased delta power during the day time and higher locomotive activity in the dark period. ISX-9 augments CaMKIIδ expression and increases BMAL1 activity via eliciting CaMKIIδ-mediated phosphorylation on BMAL1 residues S513/S515/S516, accordingly composes a positive feedback effect on enhancing circadian amplitude. CaMKIIδ-targeting, and the use of ISX-9 may serve as decent choices for treating circadian-related disorders.