Christopher Richie, Ph.D.

@article{WrightENEURO.0017-21.2021,

title = {Effects of Withdrawal from Cocaine Self-Administration on Rat Orbitofrontal Cortex Parvalbumin Neurons Expressing Cre recombinase: Sex-Dependent Changes in Neuronal Function and Unaltered Serotonin Signaling},

author = {Andrew M Wright and Agustin Zapata and Alexander F Hoffman and Julie C Necarsulmer and Lamarque M Coke and Reinis Svarcbahs and Christopher T Richie and James Pickel and Bruce T Hope and Brandon K Harvey and Carl R Lupica},

url = {https://pubmed.ncbi.nlm.nih.gov/34083381/},

doi = {10.1523/ENEURO.0017-21.2021},

year  = {2021},

date = {2021-01-01},

urldate = {2021-01-01},

journal = {eNeuro},

publisher = {Society for Neuroscience},

abstract = {The orbitofrontal cortex (OFC) is a brain region involved in higher-order decision-making. Rodent studies show that cocaine self-administration (CSA) reduces OFC contribution to goal-directed behavior and behavioral strategies to avoid drug intake. This change in OFC function persists for many weeks after cocaine withdrawal, suggesting involvement in the process of addiction. The mechanisms underlying impaired OFC function by cocaine are not well-understood. However, studies implicate altered OFC serotonin (5-HT) function in disrupted cognitive processes during addiction and other psychiatric disorders. Thus, it is hypothesized that cocaine impairment of OFC function involves changes in 5-HT signaling, and previous work shows that 5-HT1A and 5-HT2A receptor-mediated effects on OFC pyramidal neurons (PyNs) are impaired weeks after cocaine withdrawal. However, 5-HT effects on other contributors to OFC circuit function have not been fully investigated, including the parvalbumin-containing, fast-spiking interneurons (OFCPV), whose function is essential to normal OFC-mediated behavior. Here, 5-HT function in naive rats and those withdrawn from CSA were evaluated using a novel rat transgenic line in which the rat parvalbumin promoter drives Cre-recombinase expression to permit identification of OFCPV cells by fluorescent reporter protein expression. We find that whereas CSA altered basal synaptic and membrane properties of the OFCPV neurons in a sex-dependent manner, the effects of 5-HT on these cells were unchanged by CSA. These data suggest that the behavioral effects of dysregulated OFC 5-HT function caused by cocaine experience are primarily mediated by changes in 5-HT signaling at PyNs, and not at OFCPV neurons.Significance StatementCocaine addiction involves the inability to change behavior having negative consequences and to adopt beneficial behaviors. The orbitofrontal cortex (OFC) is a brain region involved in this behavioral flexibility, and OFC function is impaired after cocaine use. Moreover, signaling by the neurotransmitter serotonin (5-HT) is impaired in OFC pyramidal neurons (PyNs) after cocaine. However, whether other types of neurons are affected by cocaine is unknown, and we asked whether changes occur in another class of OFC cells known as parvalbumin interneurons. We report that cocaine changed the activity of parvalbumin interneurons in a sex-dependent manner but did not alter 5-HT effects. This suggests that the effects of cocaine on 5-HT function in OFC involves PyNs and not parvalbumin interneurons.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Garcia-Keller8463,

title = {Relapse-Associated Transient Synaptic Potentiation Requires Integrin-Mediated Activation of Focal Adhesion Kinase and Cofilin in D1-Expressing Neurons},

author = {Constanza Garcia-Keller and Michael D Scofield and Daniela Neuhofer and Swathi Varanasi and Matthew T Reeves and Brandon Hughes and Ethan Anderson and Christopher T Richie and Carlos Mejias-Aponte and James Pickel and Bruce T Hope and Brandon K Harvey and Christopher W Cowan and Peter W Kalivas},

url = {https://pubmed.ncbi.nlm.nih.gov/33051346/},

doi = {10.1523/JNEUROSCI.2666-19.2020},

issn = {0270-6474},

year  = {2020},

date = {2020-01-01},

urldate = {2020-01-01},

journal = {Journal of Neuroscience},

volume = {40},

number = {44},

pages = {8463--8477},

publisher = {Society for Neuroscience},

abstract = {Relapse to drug use can be initiated by drug-associated cues. The intensity of cue-induced drug seeking in rodent models correlates with the induction of transient synaptic potentiation (t-SP) at glutamatergic synapses in the nucleus accumbens core (NAcore). Matrix metalloproteinases (MMPs) are inducible endopeptidases that degrade extracellular matrix (ECM) proteins, and reveal tripeptide Arginine-Glycine-Aspartate (RGD) domains that bind and signal through integrins. Integrins are heterodimeric receptors composed of αβ subunits, and a primary signaling kinase is focal adhesion kinase (FAK). We previously showed that MMP activation is necessary for and potentiates cued reinstatement of cocaine seeking, and MMP-induced catalysis stimulates β3-integrins to induce t-SP. Here, we determined whether β3-integrin signaling through FAK and cofilin (actin depolymerization factor) is necessary to promote synaptic growth during t-SP. Using a small molecule inhibitor to prevent FAK activation, we blocked cued-induced cocaine reinstatement and increased spine head diameter (dh). Immunohistochemistry on NAcore labeled spines with ChR2-EYFP virus, showed increased immunoreactivity of phosphorylation of FAK (p-FAK) and p-cofilin in dendrites of reinstated animals compared with extinguished and yoked saline, and the p-FAK and cofilin depended on β3-integrin signaling. Next, male and female transgenic rats were used to selectively label D1 or D2 neurons with ChR2-mCherry. We found that p-FAK was increased during drug seeking in both D1 and D2-medium spiny neurons (MSNs), but increased p-cofilin was observed only in D1-MSNs. These data indicate that β3-integrin, FAK and cofilin constitute a signaling pathway downstream of MMP activation that is involved in promoting the transient synaptic enlargement in D1-MSNs induced during reinstated cocaine by drug-paired cues.SIGNIFICANCE STATEMENT Drug-associated cues precipitate relapse, which is correlated with transient synaptic enlargement in the accumbens core. We showed that cocaine cue-induced synaptic enlargement depends on matrix metalloprotease signaling in the extracellular matrix (ECM) through β3-integrin to activate focal adhesion kinase (FAK) and phosphorylate the actin binding protein cofilin. The nucleus accumbens core (NAcore) contains two predominate neuronal subtypes selectively expressing either D1-dopamine or D2-dopamine receptors. We used transgenic rats to study each cell type and found that cue-induced signaling through cofilin phosphorylation occurred only in D1-expressing neurons. Thus, cocaine-paired cues initiate cocaine reinstatement and synaptic enlargement through a signaling cascade selectively in D1-expressing neurons requiring ECM stimulation of β3-integrin-mediated phosphorylation of FAK (p-FAK) and cofilin.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Campbell:2019aa,

title = {Cas9 Ribonucleoprotein Complex Delivery: Methods and Applications for Neuroinflammation.},

author = {Lee A Campbell and Christopher T Richie and Nishad S Maggirwar and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/31172397},

doi = {10.1007/s11481-019-09856-z},

issn = {1557-1904 (Electronic); 1557-1890 (Linking)},

year  = {2019},

date = {2019-12-01},

urldate = {2019-12-01},

journal = {J Neuroimmune Pharmacol},

volume = {14},

number = {4},

pages = {565--577},

address = {Intramural Research Program, Biomedical Research Center, National Institute on Drug Abuse, Suite 200, 251 Bayview Blvd, Baltimore, MD, 21224, USA. lee.campbell@nih.gov.},

abstract = {The CRISPR/Cas9 system is a revolutionary gene editing technology that combines simplicity of use and efficiency of mutagenesis. As this technology progresses toward human therapies, valid concerns including off-target mutations and immunogenicity must be addressed. One approach to address these issues is to minimize the presence of the CRISPR/Cas9 components by maintaining a tighter temporal control of Cas9 endonuclease and reducing the time period of activity. This has been achieved to some degree by delivering the CRISPR/Cas9 system via pre-formed Cas9 + gRNA ribonucleoprotein (RNP) complexes. In this review, we first discuss the molecular modifications that can be made using CRISPR/Cas9 and provide an overview of current methods for delivering Cas9 RNP complexes both in vitro and in vivo. We conclude with examples of how Cas9 RNP delivery may be used to target neuroinflammatory processes, namely in regard to viral infections of the central nervous system and neurodegenerative diseases. We propose that Cas9 RNP delivery is a viable approach when considering the CRISPR/Cas9 system for both experimentation and the treatment of disease. Graphical Abstract.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hartman:2019aa,

title = {MANF deletion abrogates early larval Caenorhabditis elegans stress response to tunicamycin and Pseudomonas aeruginosa.},

author = {Jessica H Hartman and Christopher T Richie and Kacy L Gordon and Danielle F Mello and Priscila Castillo and April Zhu and Yun Wang and Barry J Hoffer and David R Sherwood and Joel N Meyer and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/31138438},

doi = {10.1016/j.ejcb.2019.05.002},

issn = {1618-1298 (Electronic); 0171-9335 (Linking)},

year  = {2019},

date = {2019-12-01},

urldate = {2019-12-01},

journal = {Eur J Cell Biol},

volume = {98},

number = {5-8},

address = {Nicholas School of the Environment, Duke University, Durham, NC, 27708, United States of America.},

abstract = {Mesencephalic astrocyte-derived neurotrophic factor (MANF) is the only human neurotrophic factor with an evolutionarily-conserved C. elegans homolog, Y54G2A.23 or manf-1. MANF is a small, soluble, endoplasmic-reticulum (ER)-resident protein that is secreted upon ER stress and promotes survival of target cells such as neurons. However, the role of MANF in ER stress and its mechanism of cellular protection are not clear and the function of MANF in C. elegans is only beginning to emerge. In this study, we show that depletion of C. elegans manf-1 causes a slight decrease in lifespan and brood size; furthermore, combined depletion of manf-1 and the IRE-1/XBP-1 ER stress/UPR pathway resulted in sterile animals that did not produce viable progeny. We demonstrate upregulation of markers of ER stress in L1 larval nematodes, as measured by hsp-3 and hsp-4 transcription, upon depletion of manf-1 by RNAi or mutation; however, there was no difference in tunicamycin-induced expression of hsp-3 and hsp-4 between wild-type and MANF-deficient worms. Surprisingly, larval growth arrest observed in wild-type nematodes reared on tunicamycin is completely prevented in the manf-1 (tm3603) mutant. Transcriptional microarray analysis revealed that manf-1 mutant L1 larvae exhibit a novel modulation of innate immunity genes in response to tunicamycin. The hypothesis that manf-1 negatively regulates the innate immunity pathway is supported by our finding that the development of manf-1 mutant larvae compared to wild-type larvae is not inhibited by growth on P. aeruginosa. Together, our data represent the first characterization of C. elegans MANF as a key modulator of organismal ER stress and immunity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Galvan:2019aa,

title = {Ultrastructural localization of DREADDs in monkeys.},

author = {Adriana Galvan and Jessica Raper and Xing Hu and Jean-Francois Pare and Jordi Bonaventura and Christopher T Richie and Michael Michaelides and Sascha A L Mueller and Patrick H Roseboom and Jonathan A Oler and Ned H Kalin and Randy A Hall and Yoland Smith},

url = {https://www.ncbi.nlm.nih.gov/pubmed/31063250},

doi = {10.1111/ejn.14429},

issn = {1460-9568 (Electronic); 0953-816X (Linking)},

year  = {2019},

date = {2019-09-01},

urldate = {2019-09-01},

journal = {Eur J Neurosci},

volume = {50},

number = {5},

pages = {2801--2813},

address = {Yerkes National Primate Research Center, Emory University, Atlanta, Georgia.},

abstract = {Designer receptors exclusively activated by designer drugs (DREADDs) are extensively used to modulate neuronal activity in rodents, but their use in primates remains limited. An essential need that remains is the demonstration that DREADDs are efficiently expressed on the plasma membrane of primate neurons. To address this issue, electron microscopy immunogold was used to determine the subcellular localization of the AAV vector-induced DREADDs hM4Di and hM3Dq fused to different tags in various brain areas of rhesus monkeys and mice. When hM4Di was fused to mCherry, the immunogold labelling was mostly confined to the intracellular space, and poorly expressed at the plasma membrane in monkey dendrites. In contrast, the hM4Di-mCherry labelling was mostly localized to the dendritic plasma membrane in mouse neurons, suggesting species differences in the plasma membrane expression of these exogenous proteins. The lack of hM4Di plasma membrane expression may limit the functional effects of systemic administration of DREADD-actuators in monkey neurons. Removing the mCherry and fusing of hM4Di with the haemagglutinin (HA) tag resulted in strong neuronal plasma membrane immunogold labelling in both monkeys and mice neurons. Finally, hM3Dq-mCherry was expressed mostly at the plasma membrane in monkey neurons, indicating that the fusion of mCherry with hM3Dq does not hamper membrane incorporation of this specific DREADD. Our results suggest that the pattern of ultrastructural expression of DREADDs in monkey neurons depends on the DREADD/tag combination. Therefore, a preliminary characterization of plasma membrane expression of specific DREADD/tag combinations is recommended when using chemogenetic approaches in primates.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Nelson:2019aa,

title = {Escalated Alcohol Self-Administration and Sensitivity to Yohimbine-Induced Reinstatement in Alcohol Preferring Rats: Potential Role of Neurokinin-1 Receptors in the Amygdala.},

author = {Britta S Nelson and Hannah D Fulenwider and Sadie E Nennig and Britessia M Smith and Michelle K Sequeira and Scott H Chimberoff and Christopher T Richie and Kejun Cheng and Kenner C Rice and Brandon K Harvey and Markus Heilig and Jesse R Schank},

url = {https://www.ncbi.nlm.nih.gov/pubmed/31242442},

doi = {10.1016/j.neuroscience.2019.06.023},

issn = {1873-7544 (Electronic); 0306-4522 (Linking)},

year  = {2019},

date = {2019-08-10},

urldate = {2019-08-10},

journal = {Neuroscience},

volume = {413},

pages = {77--85},

address = {Department of Physiology and Pharmacology, University of Georgia, Athens, Georgia.},

abstract = {Genetic factors significantly contribute to the risk for developing alcoholism. To study these factors and other associated phenotypes, rodent lines have been developed using selective breeding for high alcohol preference. One of these models, the alcohol preferring (P) rat, has been used in hundreds of preclinical studies over the last few decades. However, very few studies have examined relapse-like behavior in this rat strain. In this study, we used operant self-administration and yohimbine-induced reinstatement models to examine relapse-like behavior in P rats. Our previous work has demonstrated that P rats show increased expression of the neurokinin-1 receptor (NK1R) in the central nucleus of the amygdala (CeA), and this functionally contributes to escalated alcohol consumption in this strain. We hypothesized that P rats would show increased sensitivity to yohimbine-induced reinstatement that is also mediated by NK1R in the CeA. Using Fos staining, site-specific infusion of NK1R antagonist, and viral vector overexpression, we examined the influence of NK1R on the sensitivity to yohimbine-induced reinstatement of alcohol seeking. We found that P rats displayed increased sensitivity to yohimbine-induced reinstatement as well as increased neuronal activation in the CeA after yohimbine injection compared to the control Wistar strain. Intra-CeA infusion of NK1R antagonist attenuates yohimbine-induced reinstatement in P rats. Conversely, upregulation of NK1R within the CeA of Wistar rats increases alcohol consumption and sensitivity to yohimbine-induced reinstatement. These findings suggest that NK1R upregulation in the CeA contributes to multiple alcohol-related phenotypes in the P rat, including alcohol consumption and sensitivity to relapse.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Back:2019aab,

title = {Neuronal Activation Stimulates Cytomegalovirus Promoter-Driven Transgene Expression.},

author = {Susanne Back and Amanda Dossat and Ilmari Parkkinen and Pyry Koivula and Mikko Airavaara and Christopher T Richie and Yun-Hsiang Chen and Yun Wang and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/31380464},

doi = {10.1016/j.omtm.2019.06.006},

issn = {2329-0501 (Print); 2329-0501 (Linking)},

year  = {2019},

date = {2019-07-03},

urldate = {2019-07-03},

journal = {Mol Ther Methods Clin Dev},

volume = {14},

pages = {180--188},

address = {Molecular Mechanisms of Cellular Stress and Inflammation Section, National Institute on Drug Abuse, NIH, Baltimore, MD 21224, USA.},

abstract = {The cytomegalovirus (CMV) immediate early promoter has been extensively developed and exploited for transgene expression in vitro and in vivo, including human clinical trials. The CMV promoter has long been considered a stable, constitutive, and ubiquitous promoter for transgene expression. Using two different CMV-based promoters, we found an increase in CMV-driven transgene expression in the rodent brain and in primary neuronal cultures in response to methamphetamine, glutamate, kainic acid, and activation of G protein-coupled receptor signaling using designer receptors exclusively activated by designer drugs (DREADDs). In contrast, promoters derived from human synapsin 1 (hSYN1) gene or elongation factor 1alpha (EF1alpha) did not exhibit altered transgene expression in response to the same neuronal stimulations. Overall, our results suggest that the long-standing assertion that the CMV promoter confers constitutive expression in neurons should be reevaluated, and future studies should empirically determine the activity of the CMV promoter in a given application.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Back:2019aac,

title = {Neuron-Specific Genome Modification in the Adult Rat Brain Using CRISPR-Cas9 Transgenic Rats.},

author = {Susanne Back and Julie Necarsulmer and Leslie R Whitaker and Lamarque M Coke and Pyry Koivula and Emily J Heathward and Lowella V Fortuno and Yajun Zhang and Grace C Yeh and Heather A Baldwin and Morgan D Spencer and Carlos A Mejias-Aponte and James Pickel and Alexander F Hoffman and Charles E Spivak and Carl R Lupica and Suzanne M Underhill and Susan G Amara and Andrii Domanskyi and Jenni E Anttila and Mikko Airavaara and Bruce T Hope and Kent F Hamra and Christopher T Richie and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/30792150},

doi = {10.1016/j.neuron.2019.01.035},

issn = {1097-4199 (Electronic); 0896-6273 (Linking)},

year  = {2019},

date = {2019-04-03},

urldate = {2019-04-03},

journal = {Neuron},

volume = {102},

number = {1},

pages = {105--119},

address = {Molecular Mechanisms of Cellular Stress and Inflammation Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.},

abstract = {Historically, the rat has been the preferred animal model for behavioral studies. Limitations in genome modification have, however, caused a lag in their use compared to the bevy of available transgenic mice. Here, we have developed several transgenic tools, including viral vectors and transgenic rats, for targeted genome modification in specific adult rat neurons using CRISPR-Cas9 technology. Starting from wild-type rats, knockout of tyrosine hydroxylase was achieved with adeno-associated viral (AAV) vectors expressing Cas9 or guide RNAs (gRNAs). We subsequently created an AAV vector for Cre-dependent gRNA expression as well as three new transgenic rat lines to specifically target CRISPR-Cas9 components to dopaminergic neurons. One rat represents the first knockin rat model made by germline gene targeting in spermatogonial stem cells. The rats described herein serve as a versatile platform for making cell-specific and sequence-specific genome modifications in the adult brain and potentially other Cre-expressing tissues of the rat.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Venniro:2020fk,

title = {Abstinence-dependent dissociable central amygdala microcircuits control drug craving.},

author = {Marco Venniro and Trinity I Russell and Leslie A Ramsey and Christopher T Richie and Heidi M B Lesscher and Simone M Giovanetti and Robert O Messing and Yavin Shaham},

url = {https://www.ncbi.nlm.nih.gov/pubmed/32205443},

doi = {10.1073/pnas.2001615117},

issn = {1091-6490 (Electronic); 0027-8424 (Linking)},

year  = {2019},

date = {2019-03-23},

urldate = {2019-03-23},

journal = {Proc Natl Acad Sci U S A},

address = {Behavioral Neuroscience Branch Intramural Research Program, National Institute on Drug Abuse (NIDA), NIH, Baltimore, MD 21224; venniro.marco@nih.gov yshaham@intra.nida.nih.gov.},

abstract = {We recently reported that social choice-induced voluntary abstinence prevents incubation of methamphetamine craving in rats. This inhibitory effect was associated with activation of protein kinase-Cdelta (PKCdelta)-expressing neurons in central amygdala lateral division (CeL). In contrast, incubation of craving after forced abstinence was associated with activation of CeL-expressing somatostatin (SOM) neurons. Here we determined the causal role of CeL PKCdelta and SOM in incubation using short-hairpin RNAs against PKCdelta or SOM that we developed and validated. We injected two groups with shPKCdelta or shCtrlPKCdelta into CeL and trained them to lever press for social interaction (6 d) and then for methamphetamine infusions (12 d). We injected two other groups with shSOM or shCtrlSOM into CeL and trained them to lever press for methamphetamine infusions (12 d). We then assessed relapse to methamphetamine seeking after 1 and 15 abstinence days. Between tests, the rats underwent either social choice-induced abstinence (shPKCdelta groups) or homecage forced abstinence (shSOM groups). After test day 15, we assessed PKCdelta and SOM, Fos, and double-labeled expression in CeL and central amygdala medial division (CeM). shPKCdelta CeL injections decreased Fos in CeL PKCdelta-expressing neurons, increased Fos in CeM output neurons, and reversed the inhibitory effect of social choice-induced abstinence on incubated drug seeking on day 15. In contrast, shSOM CeL injections decreased Fos in CeL SOM-expressing neurons, decreased Fos in CeM output neurons, and decreased incubated drug seeking after 15 forced abstinence days. Our results identify dissociable central amygdala mechanisms of abstinence-dependent expression or inhibition of incubation of craving.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pardo-Garcia:2019aa,

title = {Ventral Pallidum Is the Primary Target for Accumbens D1 Projections Driving Cocaine Seeking.},

author = {Thibaut R Pardo-Garcia and Constanza Garcia-Keller and Tiffany Penaloza and Christopher T Richie and James Pickel and Bruce T Hope and Brandon K Harvey and Peter W Kalivas and Jasper A Heinsbroek},

doi = {10.1523/JNEUROSCI.2822-18.2018},

issn = {1529-2401 (Electronic); 0270-6474 (Linking)},

year  = {2019},

date = {2019-03-13},

urldate = {2019-03-13},

journal = {J Neurosci},

volume = {39},

number = {11},

pages = {2041--2051},

address = {Department of Neuroscience, University of Michigan, Ann Arbor, Michigan 48109.},

abstract = {Outputs from the nucleus accumbens (NAc) include projections to the ventral pallidum and the ventral tegmental area and subtantia nigra in the ventral mesencephalon. The medium spiny neurons (MSN) that give rise to these pathways are GABAergic and consist of two populations of equal number that are segregated by differentially expressed proteins, including D1- and D2-dopamine receptors. Afferents to the ventral pallidum arise from both D1- and D2-MSNs, whereas the ventral mesencephalon is selectively innervated by D1-MSN. To determine the extent of collateralization of D1-MSN to these axon terminal fields we used retrograde labeling in transgenic mice expressing tdTomato selectively in D1-MSN, and found that a large majority of D1-MSN in either the shell or core subcompartments of the accumbens collateralized to both output structures. Approximately 70% of D1-MSNs projecting to the ventral pallidum collateralized to the ventral mesencephalon, whereas >90% of mesencephalic D1-MSN afferents collateralized to the ventral pallidum. In contrast, <10% of dorsal striatal D1-MSNs collateralized to both the globus pallidus and ventral mesencephalon. D1-MSN activation is required for conditioned cues to induce cocaine seeking. To determine which D1-MSN projection mediates cued cocaine seeking, we selectively transfected D1-MSNs in transgenic rats with an inhibitory Gi-coupled DREADD. Activation of the transfected Gi-DREADD with clozapine-N-oxide administered into the ventral pallidum, but not into the ventral mesencephalon, blocked cue-induced cocaine seeking. These data show that, although accumbens D1-MSNs largely collateralize to both the ventral pallidum and ventral mesencephalon, only D1-MSN innervation of the ventral pallidum is necessary for cue-induced cocaine seeking.SIGNIFICANCE STATEMENT Activity in D1 dopamine receptor-expressing neurons in the NAc is required for rodents to respond to cocaine-conditioned cues and relapse to drug seeking behaviors. The D1-expressing neurons project to both the ventral pallidum and ventral mesencephalon, and we found that a majority of the neurons that innervate the ventral pallidum also collateralize to the ventral mesencephalon. However, despite innervating both structures, only D1 innervation of the ventral pallidum mediates cue-induced cocaine seeking.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Campbell:2019ab,

title = {Gesicle-Mediated Delivery of CRISPR/Cas9 Ribonucleoprotein Complex for Inactivating the HIV Provirus.},

author = {Lee A Campbell and Lamarque M Coke and Christopher T Richie and Lowella V Fortuno and Aaron Y Park and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/30389355},

doi = {10.1016/j.ymthe.2018.10.002},

issn = {1525-0024 (Electronic); 1525-0016 (Linking)},

year  = {2019},

date = {2019-01-02},

urldate = {2019-01-02},

journal = {Mol Ther},

volume = {27},

number = {1},

pages = {151--163},

address = {Intramural Research Program, National Institute on Drug Abuse, Biomedical Research Center, Suite 200, 251 Bayview Boulevard, Baltimore, MD 21224, USA. Electronic address: lee.campbell@nih.gov.},

abstract = {Investigators have utilized the CRISPR/Cas9 gene-editing system to specifically target well-conserved regions of HIV, leading to decreased infectivity and pathogenesis in vitro and ex vivo. We utilized a specialized extracellular vesicle termed a "gesicle" to efficiently, yet transiently, deliver Cas9 in a ribonucleoprotein form targeting the HIV long terminal repeat (LTR). Gesicles are produced through expression of vesicular stomatitis virus glycoprotein and package protein as their cargo, thus bypassing the need for transgene delivery, and allowing finer control of Cas9 expression. Using both NanoSight particle and western blot analysis, we verified production of Cas9-containing gesicles by HEK293FT cells. Application of gesicles to CHME-5 microglia resulted in rapid but transient transfer of Cas9 by western blot, which is present at 1 hr, but is undetectable by 24 hr post-treatment. Gesicle delivery of Cas9 protein preloaded with guide RNA targeting the HIV LTR to HIV-NanoLuc CHME-5 cells generated mutations within the LTR region and copy number loss. Finally, we demonstrated that this treatment resulted in reduced proviral activity under basal conditions and after stimulation with pro-inflammatory factors lipopolysaccharide (LPS) or tumor necrosis factor alpha (TNF-alpha). These data suggest that gesicles are a viable alternative approach to deliver CRISPR/Cas9 technology.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Trychta:2018aa,

title = {Extracellular esterase activity as an indicator of endoplasmic reticulum calcium depletion.},

author = {Kathleen A Trychta and Emily J Heathward and Agnieszka Sulima and Susanne Back and Mehdi Farokhnia and Christopher T Richie and Lorenzo Leggio and Kenner C Rice and Brandon K Harvey},

url = {https://www.ncbi.nlm.nih.gov/pubmed/30095301},

doi = {10.1080/1354750X.2018.1490968},

issn = {1366-5804 (Electronic); 1354-750X (Linking)},

year  = {2018},

date = {2018-08-10},

urldate = {2018-08-10},

journal = {Biomarkers},

pages = {1--10},

address = {a Molecular Mechanisms of Cellular Stress and Inflammation , Intramural Research Program, National Institute on Drug Abuse , Baltimore , MD , USA.},

abstract = {CONTEXT: Endoplasmic reticulum (ER) calcium depletion is associated with diverse diseases, including cardiac, hepatic, and neurologic diseases. OBJECTIVE: The aim of the present study was to identify and characterize an endogenous protein that could be used to monitor ER calcium depletion comparably to a previously described exogenous reporter protein. MATERIALS AND METHODS: The use of a selective esterase-fluorescein diester pair allowed for carboxylesterase activity in extracellular fluid to be measured using a fluorescent readout. Cell culture media from three different cell lines, rat plasma, and human serum all possess quantifiable amounts of esterase activity. RESULTS: Fluorescence produced by the interaction of carboxylesterases with a fluorescein diester substrate tracks with pharmacological and physiological inducers of ER calcium depletion. The fluorescence measured for in vitro and in vivo samples were consistent with ER calcium depletion being the trigger for increased esterase activity. DISCUSSION: Decreased luminal ER calcium causes ER resident esterases to be released from the cell, and, when assessed concurrently with other disease biomarkers, these esterases may provide insight into the role of ER calcium homeostasis in human diseases. CONCLUSION: Our results indicate that carboxylesterases are putative markers of ER calcium dysfunction.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}