scholarly journals mGlu5 Receptors and Relapse to Cocaine-Seeking: The Role of Receptor Trafficking in Postrelapse Extinction Learning Deficits

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Lori A. Knackstedt ◽  
Marek Schwendt

We have previously demonstrated that MTEP, an allosteric antagonist of mGlu5, infused into the nucleus accumbens attenuates relapse after abstinence from cocaine self-administration. MTEP infused into the dorsolateral striatum (dlSTR) does not alter relapse but has long-lasting effects on subsequent extinction learning. Here we tested whether systemic MTEP would prevent relapse after abstinence or alter extinction learning. We also investigated the mechanism of action by which intra-dlSTR MTEP on test day alters extinction on subsequent days. Animals self-administered cocaine for 12 days followed by abstinence for 20-21 days. MTEP (0.5–5 mg/kg IP) was administered prior to placement into the operant chamber for a context-primed relapse test. A separate group of animals received intra-dlSTR MTEP prior to the relapse test and were sacrificed day later. Systemic administration of MTEP attenuated abstinent-relapse without significantly affecting extinction learning. Surface biotinylation analysis of protein expression in the dlSTR revealed that, in cocaine animals, intra-dlSTR MTEP administration decreased mGlu5 surface expression and prevented changes in Arc and GluA1/GluA2 observed in their vehicle counterparts. Thus, blockade of mGlu5 receptors may be utilized in future treatment strategies for relapse prevention in humans, although the effects of chronic blockade on extinction learning should be further evaluated.

2013 ◽  
Vol 19 (1) ◽  
pp. 87-101 ◽  
Author(s):  
Lori A. Knackstedt ◽  
Heather L. Trantham-Davidson ◽  
Marek Schwendt

2020 ◽  
Author(s):  
Allison R. Bechard ◽  
Carly N. Logan ◽  
Javier Mesa ◽  
Yasmin Padovan Hernandez ◽  
Harrison Blount ◽  
...  

AbstractCeftriaxone is an antibiotic that reliably attenuates the reinstatement of cocaine-seeking after extinction while preventing the nucleus accumbens (NA) core glutamate efflux that drives reinstatement. However, when rats undergo abstinence without extinction, ceftriaxone attenuates context-primed relapse but NA core glutamate efflux still increases. Here we sought to determine if the same would occur when relapse is prompted by both context and discrete cues (context+cues) after cocaine abstinence. Male rats self-administered intravenous cocaine for 2 hr/day for 2 weeks. Cocaine delivery was accompanied by drug-associated cues (light+tone). Rats were then placed into abstinence with daily handling but no extinction training for two weeks. Ceftriaxone (200 mg/kg IP) or vehicle was administered during the last 6 days of abstinence. During a context+cue relapse test, microdialysis procedures were conducted. Rats were perfused at the end of the test for later Fos analysis. A separate cohort of rats was infused with the retrograde tracer cholera toxin B in the NA core and underwent the same self-administration and relapse procedures. Ceftriaxone increased baseline glutamate and attenuated both context+cue-primed relapse and NA core glutamate efflux during this test. Ceftriaxone reduced Fos expression in regions sending projections to the NA core (prefrontal cortex, basolateral amygdala, ventral tegmental area) and specifically reduced Fos in prelimbic cortex and not infralimbic cortex neurons projecting to the NA core. Thus, when relapse is primed by drug-associated cues and context, ceftriaxone is able to attenuate relapse by preventing NA core glutamate efflux, likely through reducing activity in prelimbic NA core-projecting neurons.


2020 ◽  
Vol 117 (42) ◽  
pp. 26460-26469 ◽  
Author(s):  
Craig T. Werner ◽  
Swarup Mitra ◽  
Benjamin D. Auerbach ◽  
Zi-Jun Wang ◽  
Jennifer A. Martin ◽  
...  

Relapse vulnerability in substance use disorder is attributed to persistent cue-induced drug seeking that intensifies (or “incubates”) during drug abstinence. Incubated cocaine seeking has been observed in both humans with cocaine use disorder and in preclinical relapse models. This persistent relapse vulnerability is mediated by neuroadaptations in brain regions involved in reward and motivation. The dorsal hippocampus (DH) is involved in context-induced reinstatement of cocaine seeking but the role of the DH in cocaine seeking during prolonged abstinence has not been investigated. Here we found that transforming growth factor-β (TGF-β) superfamily member activin A is increased in the DH on abstinence day (AD) 30 but not AD1 following extended-access cocaine self-administration compared to saline controls. Moreover, activin A does not affect cocaine seeking on AD1 but regulates cocaine seeking on AD30 in a bidirectional manner. Next, we found that activin A regulates phosphorylation of NMDA receptor (NMDAR) subunit GluN2B and that GluN2B-containing NMDARs also regulate expression of cocaine seeking on AD30. Activin A and GluN2B-containing NMDARs have both previously been implicated in hippocampal synaptic plasticity. Therefore, we examined synaptic strength in the DH during prolonged abstinence and observed an increase in moderate long-term potentiation (LTP) in cocaine-treated rats compared to saline controls. Lastly, we examined the role of DH projections to the lateral septum (LS), a brain region implicated in cocaine seeking and found that DH projections to the LS govern cocaine seeking on AD30. Taken together, this study demonstrates a role for the DH in relapse behavior following prolonged abstinence from cocaine self-administration.


Methodology ◽  
2006 ◽  
Vol 2 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Joachim Gerich ◽  
Roland Lehner

Although ego-centered network data provide information that is limited in various ways as compared with full network data, an ego-centered design can be used without the need for a priori and researcher-defined network borders. Moreover, ego-centered network data can be obtained with traditional survey methods. However, due to the dynamic structure of the questionnaires involved, a great effort is required on the part of either respondents (with self-administration) or interviewers (with face-to-face interviews). As an alternative, we will show the advantages of using CASI (computer-assisted self-administered interview) methods for the collection of ego-centered network data as applied in a study on the role of social networks in substance use among college students.


2020 ◽  
Vol 26 (34) ◽  
pp. 4234-4245
Author(s):  
Deepaneeta Sarmah ◽  
Aishika Datta ◽  
Swapnil Raut ◽  
Ankan Sarkar ◽  
Birva Shah ◽  
...  

Inflammation is a devastating outcome of cerebrovascular diseases (CVD), namely stroke and atherosclerosis. Numerous studies over the decade have shown that inflammasomes play a role in mediating inflammatory reactions post cellular injury occurring after a stroke or a rupture of an atherosclerotic plaque. In view of this, targeting these inflammatory pathways using different pharmacological therapies may improve outcomes in patients with CVD. Here, we review the mechanisms by which inflammasomes drive the pathogenesis of stroke and atherosclerosis. Also, discussed here are the possible treatment strategies available for inhibiting inflammasomes or their up-stream/down-stream mediators.


2019 ◽  
Vol 18 (8) ◽  
pp. 581-597 ◽  
Author(s):  
Ambreen Fatima ◽  
Yasir Hasan Siddique

Flavonoids are naturally occurring plant polyphenols found universally in all fruits, vegetables and medicinal plants. They have emerged as a promising candidate in the formulation of treatment strategies for various neurodegenerative disorders. The use of flavonoid rich plant extracts and food in dietary supplementation have shown favourable outcomes. The present review describes the types, properties and metabolism of flavonoids. Neuroprotective role of various flavonoids and the possible mechanism of action in the brain against the neurodegeneration have been described in detail with special emphasis on the tangeritin.


Author(s):  
Trevor Robbins

A conceptual analysis of the impulsivity construct in behavioral and neurobiological terms is followed by an analysis of its causal role in certain forms of drug addiction in both human and animal studies. The main focus of this chapter is on a rat model of impulsivity based on premature responding in the five-choice serial reaction time task and a more detailed characterization of this phenotype in neurobehavioral, neurochemical, and genetic terms. Evidence is surveyed that high impulsivity on this task is associated with the escalation subsequently of cocaine self-administration behavior and also with a tendency toward compulsive cocaine seeking. Novelty reactivity, by contrast, is associated with the enhanced acquisition of self-administration, but not with the escalation of intravenous self-administration of cocaine or the development of compulsive behavior associated with cocaine seeking. These results indicate that the vulnerability to stimulant addiction may depend on different factors, as expressed through distinct presumed endophenotypes. These observations help us further to dissociate various aspects of the impulsivity construct in neural as well as behavioral terms.


2021 ◽  
Vol 10 (14) ◽  
pp. 3129
Author(s):  
Riyaz A. Kaba ◽  
Aziz Momin ◽  
John Camm

Atrial fibrillation (AF) is a global disease with rapidly rising incidence and prevalence. It is associated with a higher risk of stroke, dementia, cognitive decline, sudden and cardiovascular death, heart failure and impairment in quality of life. The disease is a major burden on the healthcare system. Paroxysmal AF is typically managed with medications or endocardial catheter ablation to good effect. However, a large proportion of patients with AF have persistent or long-standing persistent AF, which are more complex forms of the condition and thus more difficult to treat. This is in part due to the progressive electro-anatomical changes that occur with AF persistence and the spread of arrhythmogenic triggers and substrates outside of the pulmonary veins. The posterior wall of the left atrium is a common site for these changes and has become a target of ablation strategies to treat these more resistant forms of AF. In this review, we discuss the role of the posterior left atrial wall in persistent and long-standing persistent AF, the limitations of current endocardial-focused treatment strategies, and future perspectives on hybrid epicardial–endocardial approaches to posterior wall isolation or ablation.


Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1490
Author(s):  
Osama M. Elzamzamy ◽  
Brandon E. Johnson ◽  
Wei-Chih Chen ◽  
Gangqing Hu ◽  
Reinhold Penner ◽  
...  

Multiple myeloma (MM) is a currently incurable hematologic cancer. Patients that initially respond to therapeutic intervention eventually relapse with drug resistant disease. Thus, novel treatment strategies are critically needed to improve patient outcomes. Our group has developed a novel cyclic peptide referred to as MTI-101 for the treatment of MM. We previously reported that acquired resistance to HYD-1, the linear form of MTI-101, correlated with the repression of genes involved in store operated Ca2+ entry (SOCE): PLCβ, SERCA, ITPR3, and TRPC1 expression. In this study, we sought to determine the role of TRPC1 heteromers in mediating MTI-101 induced cationic flux. Our data indicate that, consistent with the activation of TRPC heteromers, MTI-101 treatment induced Ca2+ and Na+ influx. However, replacing extracellular Na+ with NMDG did not reduce MTI-101-induced cell death. In contrast, decreasing extracellular Ca2+ reduced both MTI-101-induced Ca2+ influx as well as cell death. The causative role of TRPC heteromers was established by suppressing STIM1, TRPC1, TRPC4, or TRPC5 function both pharmacologically and by siRNA, resulting in a reduction in MTI-101-induced Ca2+ influx. Mechanistically, MTI-101 treatment induces trafficking of TRPC1 to the membrane and co-immunoprecipitation studies indicate that MTI-101 treatment induces a TRPC1-STIM1 complex. Moreover, treatment with calpeptin inhibited MTI-101-induced Ca2+ influx and cell death, indicating a role of calpain in the mechanism of MTI-101-induced cytotoxicity. Finally, components of the SOCE pathway were found to be poor prognostic indicators among MM patients, suggesting that this pathway is attractive for the treatment of MM.


Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2878
Author(s):  
Claudia Maria Hattinger ◽  
Maria Pia Patrizio ◽  
Leonardo Fantoni ◽  
Chiara Casotti ◽  
Chiara Riganti ◽  
...  

High-grade osteosarcoma (HGOS), the most common primary malignant tumor of bone, is a highly aggressive neoplasm with a cure rate of approximately 40–50% in unselected patient populations. The major clinical problems opposing the cure of HGOS are the presence of inherent or acquired drug resistance and the development of metastasis. Since the drugs used in first-line chemotherapy protocols for HGOS and clinical outcome have not significantly evolved in the past three decades, there is an urgent need for new therapeutic biomarkers and targeted treatment strategies, which may increase the currently available spectrum of cure modalities. Unresponsive or chemoresistant (refractory) HGOS patients usually encounter a dismal prognosis, mostly because therapeutic options and drugs effective for rescue treatments are scarce. Tailored treatments for different subgroups of HGOS patients stratified according to drug resistance-related biomarkers thus appear as an option that may improve this situation. This review explores drug resistance-related biomarkers, therapeutic targets and new candidate treatment strategies, which have emerged in HGOS. In addition to consolidated biomarkers, specific attention has been paid to the role of non-coding RNAs, tumor-derived extracellular vesicles, and cancer stem cells as contributors to drug resistance in HGOS, in order to highlight new candidate markers and therapeutic targets. The possible use of new non-conventional drugs to overcome the main mechanisms of drug resistance in HGOS are finally discussed.


Sign in / Sign up

Export Citation Format

Share Document