Repeated cocaine administration upregulates CB2 receptor expression in striatal medium-spiny neurons that express dopamine D1 receptors in mice
Acta pharmacologica Sinica
Zhang, HY;De Biase, L;Chandra, R;Shen, H;Liu, QR;Gardner, E;Lobo, MK;Xi, ZX;
PMID: 34316031 | DOI: 10.1038/s41401-021-00712-6
Cannabinoid CB2 receptors (CB2R) are importantly involved in drug reward and addiction. However, the cellular mechanisms underlying CB2R action remain unclear. We have previously reported that cocaine self-administration upregulates CB2R expression in midbrain dopamine (DA) neurons. In the present study, we investigated whether cocaine or heroin also alters CB2R expression in striatal medium-spiny neurons that express dopamine D1 or D2 receptors (D1-MSNs, D2-MSNs) and microglia. Due to the concern of CB2R antibody specificity, we developed three mouse CB2-specific probes to detect CB2R mRNA using quantitative RT-PCR and RNAscope in situ hybridization (ISH) assays. We found that a single injection of cocaine failed to alter, while repeated cocaine injections or self-administration dose-dependently upregulated CB2R gene expression in both brain (cortex and striatum) and periphery (spleen). In contrast, repeated administration of heroin produced a dose-dependent reduction in striatal CB2 mRNA expression. RNAscope ISH assays detected CB2R mRNA in striatal D1- and D2-MSNs, not in microglia. We then used transgenic CX3CR1eGFP/+ microglia reporter mice and D1- or D2-Cre-RiboTag mice to purify striatal microglia or ribosome-associated mRNAs from CX3CR1eGFP/+, D1-MSNs, or D2-MSNs, respectively. We found that CB2R upregulation occurred mainly in D1-MSNs, not in D2-MSNs or microglia, in the nucleus accumbens rather than the dorsal striatum. These findings indicate that repeated cocaine exposure may upregulate CB2R expression in both brain and spleen, with regional and cell type-specific profiles. In the striatum, CB2R upregulation occurs mainly in D1-MSNs in the nucleus accumbens. Given the important role of D1-MSNs in brain reward function, the present findings provide new insight into mechanisms by which brain CB2Rs modulate cocaine action.
Anesten F, Dalmau Gasull A, Richard JE, Farkas I, Mishra D, Taing L, Zhang FP, Poutanen M, Palsdottir V, Liposits Z, Skibicka KP, Jansson JO.
PMID: 31033078 | DOI: 10.1111/jne.12722
Neuronal circuits involving the central amygdala (CeA) are gaining prominence as important centers for regulation of metabolic functions. As a part of the subcortical food motivation circuitry, CeA is associated with food motivation and hunger. We have previously shown that interleukin-6 (IL-6) can act as a downstream mediator of the metabolic effects of glucagon-like peptide-1 receptor (GLP-1R) stimulation in the brain, but the sites of these effects are largely unknown. We here used the newly generated and validated RedIL6 reporter mouse strain to investigate the presence of IL-6 in the CeA, as well as possible interactions between IL-6 and GLP-1 in this nucleus. IL-6 was present in the CeA, mostly in cells in the medial and lateral parts of this structure, and a majority of IL-6-containing cells also co-expressed GLP-1R. Triple staining showed GLP-1 containing fibers co-staining with synaptophysin close to or overlapping with IL-6 containing cells. GLP-1R stimulation enhanced IL-6 mRNA levels. IL-6 receptor-alpha was found to a large part in neuronal CeA cells. Using electrophysiology, we determined that cells with neuronal properties in the CeA could be rapidly stimulated by IL-6 administration in vitro. Moreover, microinjections of IL-6 into the CeA could slightly reduce food intake in vivo in overnight fasted rats. In conclusion, IL-6 containing cells in the CeA express GLP-1R, are close to GLP-1-containing synapses, and get increased IL-6 mRNA in response to GLP-1R agonist treatment. IL-6, in turn, exerts biological effects in the CeA, possibly via IL-6 receptor-alpha present in this nucleus.
Choi MH, Na JE, Yoon YR, Lee HJ, Yoon S, Rhyu IJ, Baik JH.
PMID: 28912499 | DOI: 10.1038/s41598-017-10173-9
Dopaminergic systems play a major role in reward-related behavior and dysregulation of dopamine (DA) systems can cause several mental disorders, including depression. We previously reported that dopamine D2 receptor knockout (D2R-/-) mice display increased anxiety and depression-like behaviors upon chronic stress. Here, we observed that chronic stress caused myelin loss in wild-type (WT) mice, while the myelin level in D2R-/- mice, which was already lower than that in WT mice, was not affected upon stress. Fewer mature oligodendrocytes (OLs) were observed in the corpus callosum of stressed WT mice, while in D2R-/- mice, both the control and stressed group displayed a decrease in the number of mature OLs. We observed a decrease in the number of active β-catenin (ABC)-expressing and TCF4-expressing cells among OL lineage cells in the corpus callosum of stressed WT mice, while such regulation was not found in D2R-/- mice. Administration of lithium normalized the behavioral impairments and myelin damage induced by chronic stress in WT mice, and restored the number of ABC-positive and TCF4-positive OLs, while such effect was not found in D2R-/- mice. Together, our findings indicate that chronic stress induces myelin loss through the Wnt/β-catenin signaling pathway in association with DA signaling through D2R.
Journal of Vascular Surgery
Kasashima S, Kawashima A, Zen Y, Ozaki S, Kasashima F, Endo M, Matsumoto Y, Kawakami K.
PMID: 28434701 | DOI: 10.1016/j.jvs.2016.12.140
Abstract
OBJECTIVE:
Immunoglobulin (Ig) G4-related aortic aneurysms (IgG4-AAs) are a special aortic aneurysm among IgG4-related diseases (IgG4-RDs), which are inflammatory and fibrous conditions characterized by tumorous swelling of affected organs and high serum IgG4 concentrations. Recently, IgG4-RD pathogenesis was shown to be associated with T-helper-2 (Th2) and regulatory T (Treg) dominant cytokine production, such as interleukin (IL)-4, IL-10, and IL-13. IL-6 is a key proinflammatory cytokine contributing to lymphocyte and plasmacyte maturation and to atherosclerosis and aneurysm development. We serologically and histopathologically evaluated the cytokine profile in IgG4-AA patients.
METHODS:
Patients with IgG4-AAs (n = 10), non-IgG4-related inflammatory abdominal aortic aneurysms (non-IgG4-AAAs; n = 5), atherosclerotic AAAs (aAAAs; n = 10), and normal aortas without dilatation (n = 10) were examined for serum IL-10, IL-13, and IL-6 levels. Resected aortic tissues were evaluated for cluster of differentiation (CD) 34 (in the endothelial cells and mesenchymal cells) and CD163 (by macrophages) expression using immunohistochemistry and in situ hybridization.
RESULTS:
Serum IL-10 levels were rather higher in IgG4-AA patients (median, 1.3 pg/mL) than in non-IgG4-AAA and aAAA patients and in patients with normal aortas. Elevated serum IL-13 levels relative to standard values were detected in two IgG4-AA patients but not in the other groups. Cells immunopositive for IL-10 and IL-13 were more frequent in IgG4-AAs and significantly correlated with serum IgG4 levels. Serum IL-6 levels (median, 78.5 pg/mL) were also significantly higher in IgG4-AA patients than in non-IgG4-AAA and aAAA patients and control patients with normal aortas (P = .01, P = .001, and P = .004, respectively). They positively correlated with serum IgG4 levels and adventitial thickness, but other cytokines did not. The number of IL-6-immunopositive cells in the adventitia was significantly higher in IgG4-AA patients (median, 17.8/high-power field) than in aAAA patients or patients with normal aortas (P =.001 and P = .002, respectively). In situ hybridization confirmed frequent IL-6 messenger (m)RNA expression in the endothelium, mesenchymal cells, and histiocytes in IgG4-AA adventitia. In the same cells of IgG4-AAs, coexpression of IL-6 and CD34 mRNA or CD163 mRNA was detected.
CONCLUSIONS:
The cytokine profiles of IgG4-AA patients had two characteristics: local IL-10 and IL-13 upregulation in IgG4-AAs was related to Th2 and Treg-predominant cytokine balance, similar to other IgG4-RDs, and IL-6 upregulation in the adventitia was characterized by activated immune reactions in IgG4-AA patients. IL-6 synthesis, through contributions of mesenchymal cells and macrophages in the adventitia, is strongly involved in IgG4-AA pathogenesis or progression, or both.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
McNulty, CJ;Fallon, IP;Amat, J;Sanchez, RJ;Leslie, NR;Root, DH;Maier, SF;Baratta, MV;
PMID: 36076018 | DOI: 10.1038/s41386-022-01443-w
Stress-linked disorders are more prevalent in women than in men and differ in their clinical presentation. Thus, investigating sex differences in factors that promote susceptibility or resilience to stress outcomes, and the circuit elements that mediate their effects, is important. In male rats, instrumental control over stressors engages a corticostriatal system involving the prelimbic cortex (PL) and dorsomedial striatum (DMS) that prevent many of the sequelae of stress exposure. Interestingly, control does not buffer against stress outcomes in females, and here, we provide evidence that the instrumental controlling response in females is supported instead by the dorsolateral striatum (DLS). Additionally, we used in vivo microdialysis, fluorescent in situ hybridization, and receptor subtype pharmacology to examine the contribution of prefrontal dopamine (DA) to the differential impact of behavioral control. Although both sexes preferentially expressed D1 receptor mRNA in PL GABAergic neurons, there were robust sex differences in the dynamic properties of prefrontal DA during controllable stress. Behavioral control potently attenuated stress-induced DA efflux in males, but not females, who showed a sustained DA increase throughout the entire stress session. Importantly, PL D1 receptor blockade (SCH 23390) shifted the proportion of striatal activity from the DLS to the DMS in females and produced the protective effects of behavioral control. These findings suggest a sex-selective mechanism in which elevated DA in the PL biases instrumental responding towards prefrontal-independent striatal circuitry, thereby eliminating the protective impact of coping with stress.
Yoshimoto, S;Morita, H;Okamura, K;Hiraki, A;Hashimoto, S;
| DOI: 10.1016/j.labinv.2022.100023
Ameloblastoma (AB) is the most common benign, epithelial odontogenic tumor that occurs in the jawbone. AB is a slow-growing, benign epithelial tumor but shows locally invasive growth, with bone resorption or recurrence if not adequately resected. From these points of view, understanding the mechanism of AB-induced bone resorption is necessary for better clinical therapy and improving patients’ quality of life. In bone resorption, osteoclasts play critical roles, and RANKL is a pivotal regulator of osteoclastogenesis. However, the source of RANKL-expressing cells in the AB tumor microenvironment is controversial, and the mechanism of osteoclastogenesis in AB progression is not fully understood. In this study, we investigated the distribution of the RNA expression of RANKL in AB specimens. We found that PDGFRα- and S100A4-positive stromal fibroblasts expressed RANKL in the AB tumor microenvironment. Moreover, we analyzed the mechanisms of osteoclastogenesis in the AB tumor microenvironment using the human AB cell line AM-1 and a human primary periodontal ligament fibroblast cells. The results of histopathologic and in vitro studies clarified that the interaction between AB cells and stromal fibroblasts upregulated IL-6 expression and that AB cells induced RANKL expression in stromal fibroblasts and consequent osteoclastogenesis in AB progression.
Gupta M, Babic A, Beck AH, Terry K.
PMID: - | DOI: 10.1016/j.humpath.2016.03.006
Inflammatory cytokines, like tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6), are elevated in ovarian cancer. Differences in cytokine expression by histologic subytpe or ovarian cancer risk factors can provide useful insight into ovarian cancer risk and etiology. We used ribonucleic acid (RNA) in-situ hybridization to assess TNF-α and IL-6 expression on tissue microarray slides from 78 epithelial ovarian carcinomas (51 serous, 12 endometrioid, 7 clear cell, 2 mucinous, 6 other) from a population-based case control study. Cytokine expression was scored semi-quantitatively and odds ratios (OR) and 95% confidence intervals (CI) were calculated using polytomous logistic regression. TNF-α was expressed in 46% of the tumors while sparse IL-6 expression was seen only 18% of the tumors. For both markers, expression was most common in high grade serous carcinomas followed by endometrioid carcinomas. Parity was associated with a reduced risk of TNF-α positive (OR = 0.3, 95% CI: 0.1-0.7 for 3 or more children versus none) but not TNF-α negative tumors (p-heterogeneity = 0.02). In contrast, current smoking was associated with a nearly three fold increase in risk of TNF-α negative (OR = 2.8, 95% CI: 1.2, 6.6) but not TNF-α positive tumors (p-heterogeneity = 0.06). Our data suggests that TNF-α expression in ovarian carcinoma varies by histologic subtype and provides some support for the role of inflammation in ovarian carcinogenesis. The novel associations detected in our study need to be validated in a larger cohort of patients in future studies.
Gene-targeted, CREB-mediated induction of ΔFosB controls distinct downstream transcriptional patterns within D1 and D2 medium spiny neurons
Lardner, C;van der Zee, Y;Estill, M;Kronman, H;Salery, M;Cunningham, A;Godino, A;Parise, E;Kim, J;Neve, R;Shen, L;Hamilton, P;Nestler, E;
| DOI: 10.1016/j.biopsych.2021.06.017
Background The onset and persistence of addiction phenotypes are, in part, mediated by transcriptional mechanisms in the brain that affect gene expression and subsequently neural circuitry. ΔFosB is a transcription factor that accumulates in the nucleus accumbens (NAc) – a brain region responsible for coordinating reward and motivation – after exposure to virtually every known rewarding substance, including cocaine and opioids. ΔFosB has also been shown to directly control gene transcription and behavior downstream of both cocaine and opioid exposure, but with potentially different roles in D1 and D2 medium spiny neurons (MSNs) in NAc. Methods To clarify MSN subtype-specific roles for ΔFosB, and investigate how these coordinate the actions of distinct classes of addictive drugs in NAc, we developed a CRISPR/Cas9-based epigenome editing tool to induce endogenous ΔFosB expression in vivo in the absence of drug exposure. After inducing ΔFosB in D1 or D2 MSNs, or both, we performed RNA-sequencing on bulk male and female NAc tissue (N = 6-8/group). Results We find that ΔFosB induction elicits distinct transcriptional profiles in NAc by MSN subtype and by sex, establishing for the first time that ΔFosB mediates different transcriptional effects in males vs females. We also demonstrate that changes in D1 MSNs, but not in D2 MSNs or both, significantly recapitulate changes in gene expression induced by cocaine self-administration. Conclusions Together, these findings demonstrate the efficacy of a novel molecular tool for studying cell-type-specific transcriptional mechanisms, and shed new light on the activity of ΔFosB, a critical transcriptional regulator of drug addiction.
Zhou, K;Xu, H;Lu, S;Jiang, S;Hou, G;Deng, X;He, M;Zhu, Y;
PMID: 36271048 | DOI: 10.1038/s41467-022-33843-3
The nucleus accumbens (NAc) is critical in mediating reward seeking and is also involved in negative emotion processing, but the cellular and circuitry mechanisms underlying such opposing behaviors remain elusive. Here, using the recently developed AAV1-mediated anterograde transsynaptic tagging technique in mice, we show that NAc neurons receiving basolateral amygdala inputs (NAcBLA) promote positive reinforcement via disinhibiting dopamine neurons in the ventral tegmental area (VTA). In contrast, NAc neurons receiving paraventricular thalamic inputs (NAcPVT) innervate GABAergic neurons in the lateral hypothalamus (LH) and mediate aversion. Silencing the synaptic output of NAcBLA neurons impairs reward seeking behavior, while silencing of NAcPVT or NAcPVT→LH pathway abolishes aversive symptoms of opiate withdrawal. Our results elucidate the afferent-specific circuit architecture of the NAc in controlling reward and aversion.
Sawada R, Ku Y, Akita M, Otani K, Fujikura K, Itoh T, Ajiki T, Fukumoto T, Kakeji Y, Zen Y.
PMID: 29675965 | DOI: 10.1111/his.13633
Abstract
BACKGROUND & AIMS:
The present study aimed to elucidate the clinicopathological significance of IL-6 and IL-33 expression in intrahepatic cholangiocarcinomas (iCCAs) and perihilar cholangiocarcinomas (pCCAs).
METHODS:
IL-6 and IL-33 mRNA expression was examined in iCCAs (n=55) and pCCAs (n=32) using quantitative real-time PCR and a highly sensitive in situ hybridization protocol (RNAscope™ ), and expression values were correlated with clinicopathological features. According to a recently proposed classification scheme, iCCAs were separated into small- (n=33) and large-duct types (n=22).
RESULTS:
IL-6 and IL-33 expression levels were higher in large-duct iCCAs and pCCAs than in small-duct iCCAs, with a positive correlation between the values of these cytokines. In double in situ hybridization/immunostaining, IL-6 mRNA was expressed in actin-positive (myo)fibroblasts, while IL-33 was mainly produced by CD31-positive endothelial cells. Based on the average expression value as a cut-off point, cases were classified as IL-6high and IL-6low or IL-33high and IL-33low . In the combined cohort of large-duct iCCAs and pCCAs, IL-6high and IL-6low cholangiocarcinomas shared many features, while IL-33high cases had less aggressive characteristics than IL-33low cases as evidenced by lower tumour marker concentrations, smaller tumour sizes, less common vascular invasion, lower pT stages, and higher lymphocyte-to-monocyte ratios in blood. KRAS mutations were slightly less common in IL-33high cases than in IL-33low cancers (9% vs 29%; p=0.061). The strong expression of IL-33 in tissue appeared to be an independent favourable prognostic factor.
CONCLUSIONS:
IL-33high cholangiocarcinomas may represent a unique, less aggressive carcinogenetic process of the large bile ducts.
Frontiers in cellular neuroscience
Giua, G;Lassalle, O;Makrini-Maleville, L;Valjent, E;Chavis, P;Manzoni, OJJ;
PMID: 37323585 | DOI: 10.3389/fncel.2023.1146647
Fragile X syndrome (FXS), resulting from a mutation in the Fmr1 gene, is the most common monogenic cause of autism and inherited intellectual disability. Fmr1 encodes the Fragile X Messenger Ribonucleoprotein (FMRP), and its absence leads to cognitive, emotional, and social deficits compatible with the nucleus accumbens (NAc) dysfunction. This structure is pivotal in social behavior control, consisting mainly of spiny projection neurons (SPNs), distinguished by dopamine D1 or D2 receptor expression, connectivity, and associated behavioral functions. This study aims to examine how FMRP absence differentially affects SPN cellular properties, which is crucial for categorizing FXS cellular endophenotypes.We utilized a novel Fmr1-/y::Drd1a-tdTomato mouse model, which allows in-situ identification of SPN subtypes in FXS mice. Using RNA-sequencing, RNAScope and ex-vivo patch-clamp in adult male mice NAc, we comprehensively compared the intrinsic passive and active properties of SPN subtypes.Fmr1 transcripts and their gene product, FMRP, were found in both SPNs subtypes, indicating potential cell-specific functions for Fmr1. The study found that the distinguishing membrane properties and action potential kinetics typically separating D1- from D2-SPNs in wild-type mice were either reversed or abolished in Fmr1-/y::Drd1a-tdTomato mice. Interestingly, multivariate analysis highlighted the compound effects of Fmr1 ablation by disclosing how the phenotypic traits distinguishing each cell type in wild-type mice were altered in FXS.Our results suggest that the absence of FMRP disrupts the standard dichotomy characterizing NAc D1- and D2-SPNs, resulting in a homogenous phenotype. This shift in cellular properties could potentially underpin select aspects of the pathology observed in FXS. Therefore, understanding the nuanced effects of FMRP absence on SPN subtypes can offer valuable insights into the pathophysiology of FXS, opening avenues for potential therapeutic strategies.
Key role for hypothalamic interleukin-6 in food-motivated behavior and body weight regulation
López-Ferreras, L;Longo, F;Richard, J;Eerola, K;Shevchouk, O;Tuzinovic, M;Skibicka, K;
| DOI: 10.1016/j.psyneuen.2021.105284
The pro-inflammatory role of interleukin-6 (IL-6) is well-characterized. Blockade of IL-6, by Tocilizumab, is used in patients with rheumatoid arthritis and those diagnosed with cytokine storm. However, brain-produced IL-6 has recently emerged as a critical mediator of gut/adipose communication with the brain. Central nervous system (CNS) IL-6 is engaged by peripheral and central signals regulating energy homeostasis. IL-6 is critical for mediating hypophagia and weight loss effects of a GLP-1 analog, exendin-4, a clinically utilized drug. However, neuroanatomical substrates and behavioral mechanisms of brain IL-6 energy balance control remain poorly understood. We propose that the lateral hypothalamus (LH) is an IL-6-harboring brain region, key to food intake and food reward control. Microinjections of IL-6 into the LH reduced chow and palatable food intake in male rats. In contrast, female rats responded with reduced motivated behavior for sucrose, measured by the progressive ratio operant conditioning test, a behavioral mechanism previously not linked to IL-6. To test whether IL-6, produced in the LH, is necessary for ingestive and motivated behaviors, and body weight homeostasis, virogenetic knockdown by infusion of AAV-siRNA-IL6 into the LH was utilized. Attenuation of LH IL-6 resulted in a potent increase in sucrose-motivated behavior, without any effect on ingestive behavior or body weight in female rats. In contrast, the treatment did not affect any parameters measured (chow intake, sucrose-motivated behavior, locomotion, and body weight) in chow-fed males. However, when challenged with a high-fat/high-sugar diet, the male LH IL-6 knockdown rats displayed rapid weight gain and hyperphagia. Together, our data suggest that LH-produced IL-6 is necessary and sufficient for ingestive behavior and weight homeostasis in male rats. In females, IL-6 in the LH plays a critical role in food-motivated, but not ingestive behavior control or weight regulation. Thus, collectively these data support the idea that brain-produced IL-6 engages the hypothalamus to control feeding behavior.
