Golden SA, Jin M, Heins C, Venniro M, Michaelides M, Shaham Y.
PMID: PMID: 30655356 | DOI: DOI:10.1523/JNEUROSCI.2409-18.2019
We recently developed a mouse model of appetitive operant aggression and reported that adult male outbred CD-1 mice lever-press for the opportunity to attack subordinate male mice and relapse to aggression seeking during abstinence. Here we studied the role of nucleus accumbens (NAc) dopamine D1- and D2-receptor (Drd1 and Drd2) expressing neurons in aggression self-administration and aggression seeking. We trained CD-1 mice to self-administer intruders (9 d, 12 trials/d) and tested them for aggression self-administration and aggression seeking on abstinence day 1. We used immunohistochemistry and in situ hybridization to measure the neuronal activity marker Fos in the NAc, and cell-type specific colocalization of Fos with Drd1- and Drd2-expressing neurons. To test the causal role of Drd1- and Drd2-expressing neurons, we validated a transgenic hybrid breeding strategy crossing inbred Drd1-Cre and Drd2-Cre transgenic mice with outbred CD-1 mice and used cell-type specific Cre-DREADD (hM4Di) to inhibit NAc Drd1- and Drd2-expressing neuron activity. We found that that aggression self-administration and aggression seeking induced higher Fos expression in NAc shell than in core, that Fos colocalized with Drd1 and Drd2 in both subregions, and that chemogenetic inhibition of Drd1-, but not Drd2-, expressing neurons decreased aggression self-administration and aggression seeking. Results indicate a cell-type specific role of Drd1-expressing neurons that is critical for both aggression self-administration and aggression seeking. Our study also validates a simple breeding strategy between outbred CD-1 mice and inbred C57-based Cre lines that can be used to study cell-type and circuit mechanisms of aggression reward and relapse.SIGNIFICANCE STATEMENTAggression is often comorbid with neuropsychiatric diseases, including drug addiction. One form, appetitive aggression, exhibits symptomatology that mimics that of drug addiction and is hypothesized to be due to dysregulation of addiction-related reward circuits. However, our mechanistic understanding of the circuitry modulating appetitive operant aggression is limited. Here we use a novel mouse model of aggression self-administration and relapse, in combination with immunohistochemistry, in situ hybridization, and chemogenetic manipulations to examine how cell-types in the nucleus accumbens are recruited for, and control, operant aggression self-administration and aggression seeking on abstinence day 1. We found that one population, dopamine receptor 1-expressing neurons, act as a critical modulator of operant aggression reward and aggression seeking.
Cai, X;Liu, H;Feng, B;Yu, M;He, Y;Liu, H;Liang, C;Yang, Y;Tu, L;Zhang, N;Wang, L;Yin, N;Han, J;Yan, Z;Wang, C;Xu, P;Wu, Q;Tong, Q;He, Y;Xu, Y;
PMID: 35501380 | DOI: 10.1038/s41593-022-01062-0
Midbrain dopamine (DA) and serotonin (5-HT) neurons regulate motivated behaviors, including feeding, but less is known about how these circuits may interact. In this study, we found that DA neurons in the mouse ventral tegmental area bidirectionally regulate the activity of 5-HT neurons in the dorsal raphe nucleus (DRN), with weaker stimulation causing DRD2-dependent inhibition and overeating, while stronger stimulation causing DRD1-dependent activation and anorexia. Furthermore, in the activity-based anorexia (ABA) paradigm, which is a mouse model mimicking some clinical features of human anorexia nervosa (AN), we observed a DRD2 to DRD1 shift of DA neurotransmission on 5-HTDRN neurons, which causes constant activation of these neurons and contributes to AN-like behaviors. Finally, we found that systemic administration of a DRD1 antagonist can prevent anorexia and weight loss in ABA. Our results revealed regulation of feeding behavior by stimulation strength-dependent interactions between DA and 5-HT neurons, which may contribute to the pathophysiology of AN.
Available at SSRN 4412624
da Silva Junior, C;Grover, C;Picardo, M;Del Negro, C;
| DOI: 10.2139/ssrn.4412624
Inspiration is the inexorable active phase of breathing. The brainstem preBötzinger Complex (preBötC) gives rise to inspiratory neural rhythm but its underlying cellular and ionic bases remain unclear. The longstanding “pacemaker hypothesis” posits that persistent Na+ current (_I_NaP) that gives rise to bursting-pacemaker properties in preBötC interneurons is essential for rhythmogenesis. We tested the pacemaker hypothesis by conditionally knocking out and knocking down the _Scn8a_ (NaV1.6) gene in core rhythmogenic preBötC neurons. Deleting _Scn8a_ substantially decreased _I_NaP and abolished bursting-pacemaker activity, which slowed inspiratory rhythm in vitro and negatively impacted the postnatal development of ventilation. Diminishing _Scn8a_via genetic interference had no impact on breathing in adult mice. We argue that _Scn8a_-mediated _I_NaP is not obligatory, but it influences the development and rhythmic function of the preBötC. The ubiquity of _I_NaP in respiratory brainstem interneurons could underlie breathing-related behaviors such as neonatal phonation or rhythmogenesis in different physiological conditions.
Cholesterol-functionalized DNA/RNA heteroduplexes cross the blood-brain barrier and knock down genes in the rodent CNS
Nagata, T;Dwyer, CA;Yoshida-Tanaka, K;Ihara, K;Ohyagi, M;Kaburagi, H;Miyata, H;Ebihara, S;Yoshioka, K;Ishii, T;Miyata, K;Miyata, K;Powers, B;Igari, T;Yamamoto, S;Arimura, N;Hirabayashi, H;Uchihara, T;Hara, RI;Wada, T;Bennett, CF;Seth, PP;Rigo, F;Yokota, T;
PMID: 34385691 | DOI: 10.1038/s41587-021-00972-x
Achieving regulation of endogenous gene expression in the central nervous system (CNS) with antisense oligonucleotides (ASOs) administered systemically would facilitate the development of ASO-based therapies for neurological diseases. We demonstrate that DNA/RNA heteroduplex oligonucleotides (HDOs) conjugated to cholesterol or α-tocopherol at the 5' end of the RNA strand reach the CNS after subcutaneous or intravenous administration in mice and rats. The HDOs distribute throughout the brain, spinal cord and peripheral tissues and suppress the expression of four target genes by up to 90% in the CNS, whereas single-stranded ASOs conjugated to cholesterol have limited activity. Gene knockdown was observed in major CNS cell types and was greatest in neurons and microglial cells. Side effects, such as thrombocytopenia and focal brain necrosis, were limited by using subcutaneous delivery or by dividing intravenous injections. By crossing the blood-brain barrier more effectively, cholesterol-conjugated HDOs may overcome the limited efficacy of ASOs targeting the CNS without requiring intrathecal administration.
Didiot MC, Ferguson CM, Ly S, Coles AH, Smith AO, Bicknell AA, Hall LM, Sapp E, Echeverria D, Pai AA, DiFiglia M, Moore MJ, Hayward LJ, Aronin N, Khvorova A.
PMID: 30184490 | DOI: 10.1016/j.celrep.2018.07.106
Huntington's disease (HD) is a monogenic neurodegenerative disorder representing an ideal candidate for gene silencing with oligonucleotide therapeutics (i.e., antisense oligonucleotides [ASOs] and small interfering RNAs [siRNAs]). Using an ultra-sensitive branched fluorescence in situ hybridization (FISH) method, we show that ∼50% of wild-type HTT mRNA localizes to the nucleus and that its nuclear localization is observed only in neuronal cells. In mouse brain sections, we detect Htt mRNA predominantly in neurons, with a wide range of Htt foci observed per cell. We further show that siRNAs and ASOs efficiently eliminate cytoplasmic HTT mRNA and HTT protein, but only ASOs induce a partial but significant reduction of nuclear HTT mRNA. We speculate that, like other mRNAs, HTT mRNA subcellular localization might play a role in important neuronal regulatory mechanisms.
Sci Adv. 2018 Oct 17;4(10):eaat3386.
Ämmälä C, Drury WJ 3rd, Knerr L, Ahlstedt I, Stillemark-Billton P, Wennberg-Huldt C, Andersson EM, Valeur E, Jansson-Löfmark R, Janzén D, Sundström L, Meuller J, Claesson J, Andersson P, Johansson C, Lee RG, Prakash TP, Seth PP, Monia BP, Andersson S.
PMID: 30345352 | DOI: 10.1126/sciadv.aat3386
Antisense oligonucleotide (ASO) silencing of the expression of disease-associated genes is an attractive novel therapeutic approach, but treatments are limited by the ability to deliver ASOs to cells and tissues. Following systemic administration, ASOs preferentially accumulate in liver and kidney. Among the cell types refractory to ASO uptake is the pancreatic insulin-secreting β-cell. Here, we show that conjugation of ASOs to a ligand of the glucagon-like peptide-1 receptor (GLP1R) can productively deliver ASO cargo to pancreatic β-cells both in vitro and in vivo. Ligand-conjugated ASOs silenced target genes in pancreatic islets at doses that did not affect target gene expression in liver or other tissues, indicating enhanced tissue and cell type specificity. This finding has potential to broaden the use of ASO technology, opening up novel therapeutic opportunities, and presents an innovative approach for targeted delivery of ASOs to additional cell types.
Miao, H;Wu, F;Li, Y;Qin, C;Zhao, Y;Xie, M;Dai, H;Yao, H;Cai, H;Wang, Q;Song, X;Li, L;
PMID: 36563164 | DOI: 10.1126/sciadv.abq7289
Understanding how long noncoding RNAs (lncRNAs) cooperate with splicing factors (SFs) in alternative splicing (AS) control is fundamental to human biology and disease. We show that metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a well-documented AS-implicated lncRNA, regulates AS via two SFs, polypyrimidine tract-binding protein 1 (PTBP1) and PTB-associated SF (PSF). MALAT1 stabilizes the interaction between PTBP1 and PSF, thereby forming a functional module that affects a network of AS events. The MALAT1-stabilized PTBP1/PSF interaction occurs in multiple cellular contexts; however, the functional module, relative to MALAT1 only, has more dominant pathological significance in hepatocellular carcinoma. MALAT1 also stabilizes the PSF interaction with several heterogeneous nuclear ribonucleoparticle proteins other than PTBP1, hinting a broad role in AS control. We present a model in which MALAT1 cooperates with distinct SFs for AS regulation and pose that, relative to analyses exclusively performed for lncRNAs, a comprehensive consideration of lncRNAs and their binding partners may provide more information about their biological functions.
ACS chemical neuroscience
Dagher, M;Perrotta, KA;Erwin, SA;Hachisuka, A;Iyer, R;Masmanidis, SC;Yang, H;Andrews, AM;
PMID: 35312275 | DOI: 10.1021/acschemneuro.1c00715
Targeting neurons with light-driven opsins is widely used to investigate cell-specific responses. We transfected midbrain dopamine neurons with the excitatory opsin Chrimson. Extracellular basal and stimulated neurotransmitter levels in the dorsal striatum were measured by microdialysis in awake mice. Optical activation of dopamine cell bodies evoked terminal dopamine release in the striatum. Multiplexed analysis of dialysate samples revealed that the evoked dopamine was accompanied by temporally coupled increases in striatal 3-methoxytyramine, an extracellular dopamine metabolite, and in serotonin. We investigated a mechanism for dopamine-serotonin interactions involving striatal dopamine receptors. However, the evoked serotonin associated with optical stimulation of dopamine neurons was not abolished by striatal D1- or D2-like receptor inhibition. Although the mechanisms underlying the coupling of striatal dopamine and serotonin remain unclear, these findings illustrate advantages of multiplexed measurements for uncovering functional interactions between neurotransmitter systems. Furthermore, they suggest that the output of optogenetic manipulations may extend beyond opsin-expressing neuronal populations.
Claypool, SM;Behdin, S;Applebey, SV;Orihuel, J;Ma, Z;Reiner, DJ;
PMID: 35768212 | DOI: 10.1523/ENEURO.0496-21.2022
The orbitofrontal cortex (OFC) and piriform cortex (Pir) play a role in fentanyl relapse after food choice-induced voluntary abstinence, a procedure mimicking abstinence because of availability of alternative nondrug rewards. We used in situ hybridization and pharmacology to determine the role of OFC and Pir cannabinoid and dopamine receptors in fentanyl relapse. We trained male and female rats to self-administer food pellets for 6 d (6 h/d) and intravenous fentanyl (2.5 µg/kg/infusion) for 12 d (6 h/d). We assessed fentanyl relapse after 12 discrete choice sessions between fentanyl and food (20 trials/d), in which rats voluntarily reduced fentanyl self-administration. We used RNAscope to determine whether fentanyl relapse is associated with activity (indicated by Fos) in OFC and Pir cells expressing Cnr1 [which encodes cannabinoid 1 (CB1) receptors] or Drd1 and Drd2 (which encode dopamine D1 and D2 receptors). We injected a CB1 receptor antagonist or agonist (0.3 or 1.0 µg AM251 or WIN55,212-2/hemisphere) into OFC or a dopamine D1 receptor antagonist (1.0 or 3.0 µg SCH39166/hemisphere) into Pir to determine the effect on fentanyl relapse. Fentanyl relapse was associated with OFC cells co-expressing Fos and Cnr1 and Pir cells co-expressing Fos and Drd1 However, injections of the CB1 receptor antagonist AM251 or agonist WIN55,212-2 into OFC or the dopamine D1 receptor antagonist SCH39166 into Pir had no effect on fentanyl relapse. Fentanyl relapse is associated with activation of Cnr1-expressing OFC cells and Drd1-expressing Pir cells, but pharmacological manipulations do not support causal roles of OFC CB1 receptors or Pir dopamine D1 receptors in fentanyl relapse.
Yu Q, Hardin H, Chu YH, Rehrauer W, Lloyd RV.
PMID: 31119524 | DOI: 10.1007/s12022-019-9578-3
Parathyroid adenomas are slow growing benign neoplasms associated with hypercalcemia, while atypical parathyroid adenomas and parathyroid carcinomas are uncommon tumors and their histologic features may overlap with parathyroid adenomas. LncRNAs participate in transcription and in epigenetic or post-transcriptional regulation of gene expression, and probably contribute to carcinogenesis. We analyzed a group of normal, hyperplastic, and neoplastic parathyroid lesions to determine the best immunohistochemical markers to characterize these lesions and to determine the role of selected lncRNAs in tumor progression. A tissue microarray consisting of 111 cases of normal parathyroid (n = 14), primary hyperplasia (n = 15), secondary hyperplasia (n = 10), tertiary hyperplasia (n = 11), adenomas (n = 50), atypical adenomas (n = 7), and carcinomas (n = 4) was used. Immunohistochemical staining with antibodies against chromogranin A, synaptophysin, parathyroid hormone, and insulinoma-associated protein 1(INSM1) was used. Expression of lncRNAs including metastasis-associated lung adenocarcinoma transcript one (MALAT1), HOX transcript antisense intergenic RNA (HOTAIR), and long intergenic non-protein coding regulator of reprograming (Linc-ROR or ROR) was also analyzed by in situ hybridization and RT-PCR. All of the parathyroid tissues were positive for parathyroid hormone, while most cases were positive for chromogranin A (98%). Synaptophysin was expressed in only 12 cases (11%) and INMS1 was negative in all cases. ROR was significantly downregulated during progression from normal, hyperplastic, and adenomatous parathyroid to parathyroid carcinomas. These results show that parathyroid hormone and chromogranin A are useful markers for parathyroid neoplasms, while synaptophysin and INSM1 are not very sensitive broad-spectrum markers for these neoplasms. LincRNA ROR may function as a tumor suppressor during parathyroid tumor progression.
Zhang, Q;Tang, Q;Purohit, NM;Davenport, JB;Brennan, C;Patel, RK;Godschall, E;Zwiefel, LS;Spano, A;Campbell, JN;Güler, AD;
PMID: 36450244 | DOI: 10.1016/j.celrep.2022.111718
Obesity comorbidities such as diabetes and cardiovascular disease are pressing public health concerns. Overconsumption of calories leads to weight gain; however, neural mechanisms underlying excessive food consumption are poorly understood. Here, we demonstrate that dopamine receptor D1 (Drd1) expressed in the agouti-related peptide/neuropeptide Y (AgRP/NPY) neurons of the arcuate hypothalamus is required for appropriate responses to a high-fat diet (HFD). Stimulation of Drd1 and AgRP/NPY co-expressing arcuate neurons is sufficient to induce voracious feeding. Delivery of a HFD after food deprivation acutely induces dopamine (DA) release in the ARC, whereas animals that lack Drd1 expression in ARCAgRP/NPY neurons (Drd1AgRP-KO) exhibit attenuated foraging and refeeding of HFD. These results define a role for the DA input to the ARC that encodes acute responses to food and position Drd1 signaling in the ARCAgRP/NPY neurons as an integrator of the hedonic and homeostatic neuronal feeding circuits.
Zhang, Y;Roy, DS;Zhu, Y;Chen, Y;Aida, T;Hou, Y;Shen, C;Lea, NE;Schroeder, ME;Skaggs, KM;Sullivan, HA;Fischer, KB;Callaway, EM;Wickersham, IR;Dai, J;Li, XM;Lu, Z;Feng, G;
PMID: 35676479 | DOI: 10.1038/s41586-022-04806-x
Although bradykinesia, tremor and rigidity are the hallmark motor defects in patients with Parkinson's disease (PD), patients also experience motor learning impairments and non-motor symptoms such as depression1. The neural circuit basis for these different symptoms of PD are not well understood. Although current treatments are effective for locomotion deficits in PD2,3, therapeutic strategies targeting motor learning deficits and non-motor symptoms are lacking4-6. Here we found that distinct parafascicular (PF) thalamic subpopulations project to caudate putamen (CPu), subthalamic nucleus (STN) and nucleus accumbens (NAc). Whereas PF→CPu and PF→STN circuits are critical for locomotion and motor learning, respectively, inhibition of the PF→NAc circuit induced a depression-like state. Whereas chemogenetically manipulating CPu-projecting PF neurons led to a long-term restoration of locomotion, optogenetic long-term potentiation (LTP) at PF→STN synapses restored motor learning behaviour in an acute mouse model of PD. Furthermore, activation of NAc-projecting PF neurons rescued depression-like phenotypes. Further, we identified nicotinic acetylcholine receptors capable of modulating PF circuits to rescue different PD phenotypes. Thus, targeting PF thalamic circuits may be an effective strategy for treating motor and non-motor deficits in PD.