Eur J Neurosci. 2018 Oct 11.
Rubio FJ, Quintana-Feliciano R, Warren BL, Li X, Witonsky KFR, Soto Del Valle F, Selvam PV, Caprioli D, Venniro M, Bossert JM, Shaham Y, Hope BT.
PMID: 30307667 | DOI: 10.1111/ejn.14203
Many preclinical studies examined cue-induced relapse to heroin and cocaine seeking in animal models, but most of these studies examined only one drug at a time. In human addicts, however, polydrug use of cocaine and heroin is common. We used a polydrug self-administration relapse model in rats to determine similarities and differences in brain areas activated during cue-induced reinstatement of heroin and cocaine seeking. We trained rats to lever press for cocaine (1.0 mg/kg/infusion, 3-h/d, 18 d) or heroin (0.03 mg/kg/infusion) on alternating days (9 d for each drug); drug infusions were paired with either intermittent or continuous light cue. Next, the rats underwent extinction training followed by tests for cue-induced reinstatement where they were exposed to either heroin- or cocaine-associated cues. We observed cue-selective reinstatement of drug seeking: the heroin cue selectively reinstated heroin seeking and the cocaine cue selectively reinstated cocaine seeking. We used Fos immunohistochemistry to assess cue-induced neuronal activation in different subregions of the medial prefrontal cortex (mPFC), dorsal striatum (DS), nucleus accumbens (NAc), and amygdala. Fos expression results indicated that only the prelimbic cortex (PL) was activated by both heroin and cocaine cues; in contrast, no significant cue-induced neuronal activation was observed in other brain areas. RNA in situ hybridization indicated that the proportion of glutamatergic and GABAergic markers in PL Fos-expressing cells were similar for the heroin and cocaine cue-activated neurons. Overall the results indicate that PL may be a common brain area involved in both heroin and cocaine seeking during polydrug use.
Pharmacology Biochemistry and Behavior
Lewis MH, Rajpal H, Muehlmann AM.
PMID: - | DOI: 10.1016/j.pbb.2019.04.006
Repetitive behaviors are diagnostic for autism spectrum disorder (ASD) and commonly observed in other neurodevelopmental disorders. Currently, there are no effective pharmacological treatments for repetitive behavior in these clinical conditions. This is due to the lack of information about the specific neural circuitry that mediates the development and expression of repetitive behavior. Our previous work in mouse models has linked repetitive behavior to decreased activation of the subthalamic nucleus, a brain region in the indirect and hyperdirect pathways in the basal ganglia circuitry. The present experiments were designed to further test our hypothesis that pharmacological activation of the indirect pathway would reduce repetitive behavior. We used a combination of adenosine A1 and A2A receptor agonists that have been shown to alter the firing frequency of dorsal striatal neurons within the indirect pathway of the basal ganglia. This drug combination markedly and selectively reduced repetitive behavior in both male and female C58 mice over a six-hour period, an effect that required both A1 and A2A agonists as neither alone reduced repetitive behavior. The adenosine A1 and A2A receptor agonist combination also significantly increased the number of Fos transcripts and Fospositive cells in dorsal striatum. Fos induction was found in both direct and indirect pathway neurons suggesting that the drug combination restored the balance of activation across these complementary basal ganglia pathways. The adenosine A1 and A2A receptor agonist combination also maintained its effectiveness in reducing repetitive behavior over a 7-day period. These findings point to novel potential therapeutic targets for development of drug therapies for repetitive behavior in clinical disorders.
Nature, 493(7430), 106–110.
Barry ER, Morikawa T, Butler BL, Shrestha K, de la Rosa R, Yan KS, Fuchs CS, Magness ST, Smits R, Ogino S, Kuo CJ, Camargo FD (2012).
PMID: 23178811 | DOI: 10.1038/nature11693.
A remarkable feature of regenerative processes is their ability to halt proliferation once an organ's structure has been restored. The Wnt signalling pathway is the major driving force for homeostatic self-renewal and regeneration in the mammalian intestine. However, the mechanisms that counterbalance Wnt-driven proliferation are poorly understood. Here we demonstrate in mice and humans that yes-associated protein 1 (YAP; also known as YAP1)--a protein known for its powerful growth-inducing and oncogenic properties--has an unexpected growth-suppressive function, restricting Wnt signals during intestinal regeneration. Transgenic expression of YAP reduces Wnt target gene expression and results in the rapid loss of intestinal crypts. In addition, loss of YAP results in Wnt hypersensitivity during regeneration, leading to hyperplasia, expansion of intestinal stem cells and niche cells, and formation of ectopic crypts and microadenomas. We find that cytoplasmic YAP restricts elevated Wnt signalling independently of the AXIN-APC-GSK-3β complex partly by limiting the activity of dishevelled (DVL). DVL signals in the nucleus of intestinal stem cells, and its forced expression leads to enhanced Wnt signalling in crypts. YAP dampens Wnt signals by restricting DVL nuclear translocation during regenerative growth. Finally, we provide evidence that YAP is silenced in a subset of highly aggressive and undifferentiated human colorectal carcinomas, and that its expression can restrict the growth of colorectal carcinoma xenografts. Collectively, our work describes a novel mechanistic paradigm for how proliferative signals are counterbalanced in regenerating tissues. Additionally, our findings have important implications for the targeting of YAP in human malignancies.
Caprioli D, Venniro M, Zhang M, Bossert JM, Warren BL, Hope BT, Shaham Y.
PMID: 28123032 | DOI: 10.1523/JNEUROSCI.3091-16.2017
Abstract
We recently developed a rat model of incubation of methamphetamine craving after choice-based voluntary abstinence. Here, we studied the role of dorsolateral striatum (DLS) and dorsomedial striatum (DMS) in this incubation. We trained rats to self-administer palatable food pellets (6 d, 6 h/d) and methamphetamine (12 d, 6 h/d). We then assessed relapse to methamphetamine seeking under extinction conditions after 1 and 21 abstinence days. Between tests, the rats underwent voluntary abstinence (using a discrete choice procedure between methamphetamine and food; 20 trials/d) for 19 d. We used in situ hybridization to measure the colabeling of the activity marker Fos with Drd1 and Drd2 in DMS and DLS after the tests. Based on the in situ hybridization colabeling results, we tested the causal role of DMS D1 and D2family receptors, and DMS neuronal ensembles in "incubated" methamphetamine seeking, using selective dopamine receptor antagonists (SCH39166 or raclopride) and the Daun02 chemogenetic inactivation procedure, respectively. Methamphetamine seeking was higher after 21 d of voluntary abstinence than after 1 d (incubation of methamphetamine craving). The incubated response was associated with increased Fos expression in DMS but not in DLS; Fos was colabeled with both Drd1 and Drd2 DMS injections of SCH39166 or raclopride selectively decreased methamphetamine seeking after 21 abstinence days. In Fos-lacZ transgenic rats, selective inactivation of relapse test-activated Fos neurons in DMS on abstinence day 18 decreased incubated methamphetamine seeking on day 21. Results demonstrate a role of DMS dopamine D1 and D2 receptors in the incubation of methamphetamine craving after voluntary abstinence and that DMS neuronal ensembles mediate this incubation.
SIGNIFICANCE STATEMENT:
In human addicts, abstinence is often self-imposed and relapse can be triggered by exposure to drug-associated cues that induce drug craving. We recently developed a rat model of incubation of methamphetamine craving after choice-based voluntary abstinence. Here, we used classical pharmacology, in situ hybridization, immunohistochemistry, and the Daun02 inactivation procedure to demonstrate a critical role of dorsomedial striatum neuronal ensembles in this new form of incubation of drug craving.
Bernanke, A;Burnette, E;Murphy, J;Hernandez, N;Zimmerman, S;Walker, QD;Wander, R;Sette, S;Reavis, Z;Francis, R;Armstrong, C;Risher, ML;Kuhn, C;
PMID: 34898621 | DOI: 10.1371/journal.pone.0260577
Females are more affected by psychiatric illnesses including eating disorders, depression, and post-traumatic stress disorder than males. However, the neural mechanisms mediating these sex differences are poorly understood. Animal models can be useful in exploring such neural mechanisms. Conditioned taste aversion (CTA) is a behavioral task that assesses how animals process the competition between associated reinforcing and aversive stimuli in subsequent task performance, a process critical to healthy behavior in many domains. The purpose of the present study was to identify sex differences in this behavior and associated neural responses. We hypothesized that females would value the rewarding stimulus (Boost ) relative to the aversive stimulus (LiCl) more than males in performing CTA. We evaluated behavior (Boost intake, LiCl-induced behaviors, ultrasonic vocalizations (USVs), CTA performance) and Fos activation in relevant brain regions after the acute stimuli [acute Boost (AB), acute LiCl (AL)] and the context-only task control (COT), Boost only task (BOT) and Boost -LiCl task (BLT). Acutely, females drank more Boost than males but showed similar aversive behaviors after LiCl. Females and males performed CTA similarly. Both sexes produced 55 kHz USVs anticipating BOT and inhibited these calls in the BLT. However, more females emitted both 22 kHz and 55 kHz USVs in the BLT than males: the latter correlated with less CTA. Estrous cycle stage also influenced 55 kHz USVs. Fos responses were similar in males and females after AB or AL. Females engaged the gustatory cortex and ventral tegmental area (VTA) more than males during the BOT and males engaged the amygdala more than females in both the BOT and BLT. Network analysis of correlated Fos responses across brain regions identified two unique networks characterizing the BOT and BLT, in both of which the VTA played a central role. In situ hybridization with RNAscope identified a population of D1-receptor expressing cells in the CeA that responded to Boost and D2 receptor-expressing cells that responded to LiCl. The present study suggests that males and females differentially process the affective valence of a stimulus to produce the same goal-directed behavior.
Singh, PNP;Madha, S;Leiter, AB;Shivdasani, RA;
PMID: 35738677 | DOI: 10.1101/gad.349412.122
The progeny of intestinal stem cells (ISCs) dedifferentiate in response to ISC attrition. The precise cell sources, transitional states, and chromatin remodeling behind this activity remain unclear. In the skin, stem cell recovery after injury preserves an epigenetic memory of the damage response; whether similar memories arise and persist in regenerated ISCs is not known. We addressed these questions by examining gene activity and open chromatin at the resolution of single Neurog3-labeled mouse intestinal crypt cells, hence deconstructing forward and reverse differentiation of the intestinal secretory (Sec) lineage. We show that goblet, Paneth, and enteroendocrine cells arise by multilineage priming in common precursors, followed by selective access at thousands of cell-restricted cis-elements. Selective ablation of the ISC compartment elicits speedy reversal of chromatin and transcriptional features in large fractions of precursor and mature crypt Sec cells without obligate cell cycle re-entry. ISC programs decay and reappear along a cellular continuum lacking discernible discrete interim states. In the absence of gross tissue damage, Sec cells simply reverse their forward trajectories, without invoking developmental or other extrinsic programs, and starting chromatin identities are effectively erased. These findings identify strikingly plastic molecular frameworks in assembly and regeneration of a self-renewing tissue.
Zhang, K;Erkan, EP;Jamalzadeh, S;Dai, J;Andersson, N;Kaipio, K;Lamminen, T;Mansuri, N;Huhtinen, K;Carpén, O;Hietanen, S;Oikkonen, J;Hynninen, J;Virtanen, A;Häkkinen, A;Hautaniemi, S;Vähärautio, A;
PMID: 35196078 | DOI: 10.1126/sciadv.abm1831
Chemotherapy resistance is a critical contributor to cancer mortality and thus an urgent unmet challenge in oncology. To characterize chemotherapy resistance processes in high-grade serous ovarian cancer, we prospectively collected tissue samples before and after chemotherapy and analyzed their transcriptomic profiles at a single-cell resolution. After removing patient-specific signals by a novel analysis approach, PRIMUS, we found a consistent increase in stress-associated cell state during chemotherapy, which was validated by RNA in situ hybridization and bulk RNA sequencing. The stress-associated state exists before chemotherapy, is subclonally enriched during the treatment, and associates with poor progression-free survival. Co-occurrence with an inflammatory cancer-associated fibroblast subtype in tumors implies that chemotherapy is associated with stress response in both cancer cells and stroma, driving a paracrine feed-forward loop. In summary, we have found a resistant state that integrates stromal signaling and subclonal evolution and offers targets to overcome chemotherapy resistance.
Kiss1 is differentially regulated in male and female mice by the homeodomain transcription factor VAX1
Molecular and cellular endocrinology
Lavalle, SN;Chou, T;Hernandez, J;Naing, NCP;Tonsfeldt, KJ;Hoffmann, HM;Mellon, PL;
PMID: 34098016 | DOI: 10.1016/j.mce.2021.111358
Regulation of Kiss1 transcription is crucial to the development and function of the reproductive axis. The homeodomain transcription factor, ventral anterior homeobox 1 (VAX1), has been implicated as a potential regulator of Kiss1 transcription. However, it is unknown whether VAX1 directly mediates transcription within kisspeptin neurons or works indirectly by acting upstream of kisspeptin neuron populations. This study tested the hypothesis that VAX1 within kisspeptin neurons regulates Kiss1 gene expression. We found that VAX1 acts as a repressor of Kiss1 in vitro and within the male arcuate nucleus in vivo. In female mice, we found that the loss of VAX1 caused a reduction in Kiss1 expression and Kiss1-containing neurons in the anteroventral periventricular nucleus at the time of the preovulatory luteinizing hormone surge, but was compensated by an increase in Kiss1-cFos colocalization. Despite changes in Kiss1 transcription, gonadotropin levels were unaffected and there were no impairments to fertility.
Cell Mol Gastroenterol Hepatol.
Montenegro-Miranda PS, van der Meer JHM, Jones C, Meisner S, Vermeulen JLM, Koster J, Wildenberg ME, Heijmans J, Boudreau F, Ribeiro A, van den Brink GR, Muncan V
PMID: 32145468 | DOI: 10.1016/j.jcmgh.2020.02.007
BACKGROUND & AIMS:
Recent evidence has suggested that the intact intestinal epithelial barrier protects our body from a range of immune-mediated diseases. The epithelial layer has an impressive ability to reconstitute and repair upon damage and this process of repair increasingly is seen as a therapeutic target. In vitro models to study this process in primary intestinal cells are lacking.
METHODS:
We established and characterized an in vitro model of intestinal damage and repair by applying ?-radiation on small-intestinal organoids. We then used this model to identify novel regulators of intestinal regeneration.
RESULTS:
We identified hepatocyte nuclear factor 4? (HNF4?) as a pivotal upstream regulator of the intestinal regenerative response. Organoids lacking Hnf4a were not able to propagate in vitro. Importantly, intestinal Hnf4a knock-out mice showed impaired regeneration after whole-body irradiation, confirming intestinal organoids as a valuable alternative to in vivo studies.
CONCLUSIONS:
In conclusion, we established and validated an in vitro damage-repair model and identified HNF4? as a crucial regulator of intestinal regeneration
Childs, CJ;Holloway, EM;Sweet, CW;Tsai, YH;Wu, A;Vallie, A;Eiken, MK;Capeling, MM;Zwick, RK;Palikuqi, B;Trentesaux, C;Wu, JH;Pellon-Cardenas, O;Zhang, CJ;Glass, IA;Loebel, C;Yu, Q;Camp, JG;Sexton, JZ;Klein, OD;Verzi, MP;Spence, JR;
PMID: 36821371 | DOI: 10.1172/jci.insight.165566
Epithelial organoids derived from intestinal tissue, called 'enteroids', recapitulate many aspects of the organ in vitro, and can be used for biological discovery, personalized medicine, and drug development. Here, we interrogated the cell signaling environment within the developing human intestine to identify niche cues that may be important for epithelial development and homeostasis. We identify an EGF family member, EPIREGULIN (EREG), which is robustly expressed in the developing human crypt. Enteroids generated from the developing human intestine grown in standard culture conditions, which contain EGF, are dominated by stem and progenitor cells, feature little differentiation and no spatial organization. Our results demonstrate that EREG can replace EGF in vitro, and EREG leads to spatially resolved enteroids that feature budded and proliferative crypt domains and a differentiated villus-like central lumen. Multiomic (transcriptome plus epigenome) profiling of native crypts, EGF-grown and EREG-grown enteroids show that EGF-enteroids have an altered chromatin landscape that is dependent on EGF concentration, downregulate the master intestinal transcription factor CDX2, and ectopically express stomach genes, a phenomenon that is reversible. This is in contrast to EREG-grown enteroids, which remain intestine-like in culture. Thus, EREG creates a homeostatic intestinal niche in vitro, enabling interrogation of stem cell function, cellular differentiation, and disease modeling.
Dohnalová, L;Lundgren, P;Carty, JRE;Goldstein, N;Wenski, SL;Nanudorn, P;Thiengmag, S;Huang, KP;Litichevskiy, L;Descamps, HC;Chellappa, K;Glassman, A;Kessler, S;Kim, J;Cox, TO;Dmitrieva-Posocco, O;Wong, AC;Allman, EL;Ghosh, S;Sharma, N;Sengupta, K;Cornes, B;Dean, N;Churchill, GA;Khurana, TS;Sellmyer, MA;FitzGerald, GA;Patterson, AD;Baur, JA;Alhadeff, AL;Helfrich, EJN;Levy, M;Betley, JN;Thaiss, CA;
PMID: 36517598 | DOI: 10.1038/s41586-022-05525-z
Exercise exerts a wide range of beneficial effects for healthy physiology1. However, the mechanisms regulating an individual's motivation to engage in physical activity remain incompletely understood. An important factor stimulating the engagement in both competitive and recreational exercise is the motivating pleasure derived from prolonged physical activity, which is triggered by exercise-induced neurochemical changes in the brain. Here, we report on the discovery of a gut-brain connection in mice that enhances exercise performance by augmenting dopamine signalling during physical activity. We find that microbiome-dependent production of endocannabinoid metabolites in the gut stimulates the activity of TRPV1-expressing sensory neurons and thereby elevates dopamine levels in the ventral striatum during exercise. Stimulation of this pathway improves running performance, whereas microbiome depletion, peripheral endocannabinoid receptor inhibition, ablation of spinal afferent neurons or dopamine blockade abrogate exercise capacity. These findings indicate that the rewarding properties of exercise are influenced by gut-derived interoceptive circuits and provide a microbiome-dependent explanation for interindividual variability in exercise performance. Our study also suggests that interoceptomimetic molecules that stimulate the transmission of gut-derived signals to the brain may enhance the motivation for exercise.
Li, L;Durand-de Cuttoli, R;Aubry, AV;Burnett, CJ;Cathomas, F;Parise, LF;Chan, KL;Morel, C;Yuan, C;Shimo, Y;Lin, HY;Wang, J;Russo, SJ;
PMID: 36450985 | DOI: 10.1038/s41586-022-05484-5
In humans, traumatic social experiences can contribute to psychiatric disorders1. It is suggested that social trauma impairs brain reward function such that social behaviour is no longer rewarding, leading to severe social avoidance2,3. In rodents, the chronic social defeat stress (CSDS) model has been used to understand the neurobiology underlying stress susceptibility versus resilience following social trauma, yet little is known regarding its impact on social reward4,5. Here we show that, following CSDS, a subset of male and female mice, termed susceptible (SUS), avoid social interaction with non-aggressive, same-sex juvenile C57BL/6J mice and do not develop context-dependent social reward following encounters with them. Non-social stressors have no effect on social reward in either sex. Next, using whole-brain Fos mapping, in vivo Ca2+ imaging and whole-cell recordings, we identified a population of stress/threat-responsive lateral septum neurotensin (NTLS) neurons that are activated by juvenile social interactions only in SUS mice, but not in resilient or unstressed control mice. Optogenetic or chemogenetic manipulation of NTLS neurons and their downstream connections modulates social interaction and social reward. Together, these data suggest that previously rewarding social targets are possibly perceived as social threats in SUS mice, resulting from hyperactive NTLS neurons that occlude social reward processing.
