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Acta Pharmacologica Sinica Dec 2018Drug addiction is a chronic, relapsing brain disorder. Multiple neural networks in the brain including the reward system (e.g., the mesocorticolimbic system), the... (Review)
Review
Drug addiction is a chronic, relapsing brain disorder. Multiple neural networks in the brain including the reward system (e.g., the mesocorticolimbic system), the anti-reward/stress system (e.g., the extended amygdala), and the central immune system, are involved in the development of drug addiction and relapse after withdrawal from drugs of abuse. Preclinical and clinical studies have demonstrated that it is promising to control drug addiction by pharmacologically targeting the addiction-related systems in the brain. Here we review the pharmacological targets within the dopamine system, glutamate system, trace amine system, anti-reward system, and central immune system, which are of clinical interests. Furthermore, we discuss other potential therapies, e.g., brain stimulation, behavioral treatments, and therapeutic gene modulation, which could be effective to treat drug addiction. We conclude that, although drug addiction is a complex disorder that involves complicated neural mechanisms and psychological processes, this mental disorder is treatable and may be curable by therapies such as gene modulation in the future.
Topics: Animals; Behavior Therapy; Brain; Dopamine Antagonists; Electric Stimulation Therapy; Excitatory Amino Acid Antagonists; Genetic Therapy; Humans; Receptors, G-Protein-Coupled; Substance-Related Disorders
PubMed: 30382181
DOI: 10.1038/s41401-018-0180-x -
Neuron Apr 2019Obsessive-compulsive disorder is a severe and disabling psychiatric disorder that presents several challenges for neuroscience. Recent advances in its genetic and... (Review)
Review
Obsessive-compulsive disorder is a severe and disabling psychiatric disorder that presents several challenges for neuroscience. Recent advances in its genetic and developmental causation, as well as its neuropsychological basis, are reviewed. Hypotheses concerning an imbalance between goal-directed and habitual behavior together with neural correlates in cortico-striatal circuitry are evaluated and contrasted with metacognitive theories. Treatments for obsessive-compulsive disorder (OCD) tend to be of mixed efficacy but include psychological, pharmacological, and surgical approaches, the underlying mechanisms of which are still under debate. Overall, the prospects for new animal models and an integrated understanding of the pathophysiology of OCD are considered in the context of dimensional psychiatry.
Topics: Animals; Anxiety; Anxiety Disorders; Brain; Cognitive Behavioral Therapy; Compulsive Behavior; Disease Models, Animal; Dopamine Antagonists; Food Addiction; Functional Neuroimaging; Gambling; Genetic Predisposition to Disease; Gyrus Cinguli; Humans; Implosive Therapy; Magnetic Resonance Imaging; Neurosurgical Procedures; Obsessive-Compulsive Disorder; Phenotype; Positron-Emission Tomography; Selective Serotonin Reuptake Inhibitors; Substance-Related Disorders
PubMed: 30946823
DOI: 10.1016/j.neuron.2019.01.046 -
Progress in Retinal and Eye Research Nov 2017In the face of an "epidemic" increase in myopia over the last decades and myopia prevalence predicted to reach 2.5 billion people by the end of this decade, there is an... (Review)
Review
In the face of an "epidemic" increase in myopia over the last decades and myopia prevalence predicted to reach 2.5 billion people by the end of this decade, there is an urgent need to develop effective and safe therapeutic interventions to slow down this "myopia booming" and prevent myopia-related complications and vision loss. Dopamine (DA) is an important neurotransmitter in the retina and mediates diverse functions including retina development, visual signaling, and refractive development. Inspired by the convergence of epidemiological and animal studies in support of the inverse relationship between outdoor activity and risk of developing myopia and by the close biological relationship between light exposure and dopamine release/signaling, we felt it is timely and important to critically review the role of DA in myopia development. This review will revisit several key points of evidence for and against DA mediating light control of myopia: 1) the causal role of extracellular retinal DA levels, 2) the mechanism and action of dopamine D1 and D2 receptors and 3) the roles of cellular/circuit retinal pathways. We examine the experiments that show causation by altering DA, DA receptors and visual pathways using pharmacological, transgenic, or visual environment approaches. Furthermore, we critically evaluate the safety issues of a DA-based treatment strategy and some approaches to address these issues. The review identifies the key questions and challenges in translating basic knowledge on DA signaling and myopia from animal studies into effective pharmacological treatments for myopia in children.
Topics: Dopamine; Dopamine Agonists; Dopamine Antagonists; Eye; Humans; Myopia; Receptors, Dopamine; Retina; Signal Transduction
PubMed: 28602573
DOI: 10.1016/j.preteyeres.2017.06.003 -
Neurotherapeutics : the Journal of the... Apr 2018Migraine is a common and disabling primary headache disorder with a significant socioeconomic burden. The management of migraine is multifaceted and is generally... (Review)
Review
Migraine is a common and disabling primary headache disorder with a significant socioeconomic burden. The management of migraine is multifaceted and is generally dichotomized into acute and preventive strategies, with several treatment modalities. The aims of acute pharmacological treatment are to rapidly restore function with minimal recurrence, with the avoidance of side effects. The choice of pharmacological treatment is individualized, and is based on the consideration of the characteristics of the migraine attack, the patient's concomitant medical problems, and treatment preferences. Notwithstanding, a good understanding of the pharmacodynamic and pharmacokinetic properties of the various drug options is essential to guide therapy. The current approach and concepts relevant to the acute pharmacological treatment of migraine will be explored in this review.
Topics: Acetaminophen; Analgesics, Opioid; Animals; Anti-Inflammatory Agents, Non-Steroidal; Dopamine Antagonists; Ergot Alkaloids; Humans; Migraine Disorders; Tryptamines
PubMed: 29235068
DOI: 10.1007/s13311-017-0592-1 -
Psychiatria Polska 2016BPSD (Behavioral and Psychological Symptoms in Dementia) affects virtually all patients with dementia. The aim of this review is to present information on epidemiology,... (Review)
Review
BPSD (Behavioral and Psychological Symptoms in Dementia) affects virtually all patients with dementia. The aim of this review is to present information on epidemiology, consequences and evidence-based non-pharmacological and pharmacological treatment approaches. The review also covers recent literature derived from a systematic literature Medline search on BPSD. Results indicate that BPSD are major risk factors for an earlier placement of affected individuals in nursing homes and a potentially more severe course of dementia over time. Treatment of BPSD is complex and includes both strategies.
Topics: Aggression; Anticonvulsants; Antipsychotic Agents; Behavioral Symptoms; Clinical Protocols; Conduct Disorder; Dementia; Dopamine Antagonists; Female; Geriatric Psychiatry; Humans; Male; Neurocognitive Disorders; Severity of Illness Index
PubMed: 27847922
DOI: 10.12740/PP/64477 -
Gastroenterology Apr 2023Although there have been multiple drugs tested in gastroparesis, their relative efficacy and safety are unknown. We evaluated this in a network meta-analysis of... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Although there have been multiple drugs tested in gastroparesis, their relative efficacy and safety are unknown. We evaluated this in a network meta-analysis of randomized controlled trials (RCTs).
METHODS
We searched the literature to September 7, 2022. We judged the efficacy of drugs based on global symptoms of gastroparesis; individual symptoms, including nausea, vomiting, abdominal pain, bloating, or fullness; and safety according to total adverse events and adverse events leading to withdrawal. We extracted data as intention-to-treat analyses, assuming dropouts to be treatment failures and reporting pooled relative risks (RRs) of not improving with 95% confidence intervals (CIs), ranking drugs according to P-score.
RESULTS
We identified 29 RCTs (3772 patients). Based on global symptoms, clebopride ranked first for efficacy (RR, 0.30; 95% CI, 0.16-0.57; P-score = .99) followed by domperidone (RR, 0.68; 95% CI, 0.48-0.98; P-score = .76). No other drug was superior to placebo. Only 2 drug classes were efficacious: in rank order, oral dopamine antagonists (RR, 0.58; 95% CI, 0.44-0.77; P-score = .96) and tachykinin-1 antagonists (RR, 0.69; 95% CI, 0.52-0.93; P-score = .83). For individual symptoms, oral metoclopramide ranked first for nausea (RR 0.46; 95% CI, 0.21-1.00; P-score = .95), fullness (RR 0.67; 95% CI, 0.35-1.28; P-score = .86), and bloating (RR 0.53; 95% CI, 0.30-0.93; P-score = .97), based on only 1 small trial. Only prucalopride was more likely to be associated with adverse events than placebo.
CONCLUSIONS
In a network meta-analysis, oral dopamine antagonists and tachykinin-1 antagonists were more efficacious than placebo for gastroparesis, but confidence in the evidence was low to moderate for most comparisons. There is an unmet need for efficacious therapies for gastroparesis.
Topics: Humans; Gastroparesis; Network Meta-Analysis; Nausea; Dopamine Antagonists; Tachykinins
PubMed: 36581089
DOI: 10.1053/j.gastro.2022.12.014 -
The Cochrane Database of Systematic... Aug 2020The symptoms and signs of schizophrenia have been linked to high levels of dopamine in specific areas of the brain (limbic system). Antipsychotic drugs block the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The symptoms and signs of schizophrenia have been linked to high levels of dopamine in specific areas of the brain (limbic system). Antipsychotic drugs block the transmission of dopamine in the brain and reduce the acute symptoms of the disorder. An original version of the current review, published in 2012, examined whether antipsychotic drugs are also effective for relapse prevention. This is the updated version of the aforesaid review.
OBJECTIVES
To review the effects of maintaining antipsychotic drugs for people with schizophrenia compared to withdrawing these agents.
SEARCH METHODS
We searched the Cochrane Schizophrenia Group's Study-Based Register of Trials including the registries of clinical trials (12 November 2008, 10 October 2017, 3 July 2018, 11 September 2019).
SELECTION CRITERIA
We included all randomised trials comparing maintenance treatment with antipsychotic drugs and placebo for people with schizophrenia or schizophrenia-like psychoses.
DATA COLLECTION AND ANALYSIS
We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CIs) on an intention-to-treat basis based on a random-effects model. For continuous data, we calculated mean differences (MD) or standardised mean differences (SMD), again based on a random-effects model.
MAIN RESULTS
The review currently includes 75 randomised controlled trials (RCTs) involving 9145 participants comparing antipsychotic medication with placebo. The trials were published from 1959 to 2017 and their size ranged between 14 and 420 participants. In many studies the methods of randomisation, allocation and blinding were poorly reported. However, restricting the analysis to studies at low risk of bias gave similar results. Although this and other potential sources of bias limited the overall quality, the efficacy of antipsychotic drugs for maintenance treatment in schizophrenia was clear. Antipsychotic drugs were more effective than placebo in preventing relapse at seven to 12 months (primary outcome; drug 24% versus placebo 61%, 30 RCTs, n = 4249, RR 0.38, 95% CI 0.32 to 0.45, number needed to treat for an additional beneficial outcome (NNTB) 3, 95% CI 2 to 3; high-certainty evidence). Hospitalisation was also reduced, however, the baseline risk was lower (drug 7% versus placebo 18%, 21 RCTs, n = 3558, RR 0.43, 95% CI 0.32 to 0.57, NNTB 8, 95% CI 6 to 14; high-certainty evidence). More participants in the placebo group than in the antipsychotic drug group left the studies early due to any reason (at seven to 12 months: drug 36% versus placebo 62%, 24 RCTs, n = 3951, RR 0.56, 95% CI 0.48 to 0.65, NNTB 4, 95% CI 3 to 5; high-certainty evidence) and due to inefficacy of treatment (at seven to 12 months: drug 18% versus placebo 46%, 24 RCTs, n = 3951, RR 0.37, 95% CI 0.31 to 0.44, NNTB 3, 95% CI 3 to 4). Quality of life might be better in drug-treated participants (7 RCTs, n = 1573 SMD -0.32, 95% CI to -0.57 to -0.07; low-certainty evidence); probably the same for social functioning (15 RCTs, n = 3588, SMD -0.43, 95% CI -0.53 to -0.34; moderate-certainty evidence). Underpowered data revealed no evidence of a difference between groups for the outcome 'Death due to suicide' (drug 0.04% versus placebo 0.1%, 19 RCTs, n = 4634, RR 0.60, 95% CI 0.12 to 2.97,low-certainty evidence) and for the number of participants in employment (at 9 to 15 months, drug 39% versus placebo 34%, 3 RCTs, n = 593, RR 1.08, 95% CI 0.82 to 1.41, low certainty evidence). Antipsychotic drugs (as a group and irrespective of duration) were associated with more participants experiencing movement disorders (e.g. at least one movement disorder: drug 14% versus placebo 8%, 29 RCTs, n = 5276, RR 1.52, 95% CI 1.25 to 1.85, number needed to treat for an additional harmful outcome (NNTH) 20, 95% CI 14 to 50), sedation (drug 8% versus placebo 5%, 18 RCTs, n = 4078, RR 1.52, 95% CI 1.24 to 1.86, NNTH 50, 95% CI not significant), and weight gain (drug 9% versus placebo 6%, 19 RCTs, n = 4767, RR 1.69, 95% CI 1.21 to 2.35, NNTH 25, 95% CI 20 to 50).
AUTHORS' CONCLUSIONS
For people with schizophrenia, the evidence suggests that maintenance on antipsychotic drugs prevents relapse to a much greater extent than placebo for approximately up to two years of follow-up. This effect must be weighed against the adverse effects of antipsychotic drugs. Future studies should better clarify the long-term morbidity and mortality associated with these drugs.
Topics: Antipsychotic Agents; Bias; Dopamine Antagonists; Employment; Hospitalization; Humans; Maintenance Chemotherapy; Patient Dropouts; Placebos; Quality of Life; Randomized Controlled Trials as Topic; Recurrence; Schizophrenia; Secondary Prevention
PubMed: 32840872
DOI: 10.1002/14651858.CD008016.pub3 -
Critical Care (London, England) Aug 2016Intolerance to enteral nutrition is common in critically ill adults, and may result in significant morbidity including ileus, abdominal distension, vomiting and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Intolerance to enteral nutrition is common in critically ill adults, and may result in significant morbidity including ileus, abdominal distension, vomiting and potential aspiration events. Prokinetic agents are prescribed to improve gastric emptying. However, the efficacy and safety of these agents in critically ill patients is not well-defined. Therefore, we conducted a systematic review and meta-analysis to determine the efficacy and safety of prokinetic agents in critically ill patients.
METHODS
We searched MEDLINE, EMBASE, and Cochrane Library from inception up to January 2016. Eligible studies included randomized controlled trials (RCTs) of critically ill adults assigned to receive a prokinetic agent or placebo, and that reported relevant clinical outcomes. Two independent reviewers screened potentially eligible articles, selected eligible studies, and abstracted pertinent data. We calculated pooled relative risk (RR) for dichotomous outcomes and mean difference for continuous outcomes, with the corresponding 95 % confidence interval (CI). We assessed risk of bias using Cochrane risk of bias tool, and the quality of evidence using grading of recommendations assessment, development, and evaluation (GRADE) methodology.
RESULTS
Thirteen RCTs (enrolling 1341 patients) met our inclusion criteria. Prokinetic agents significantly reduced feeding intolerance (RR 0.73, 95 % CI 0.55, 0.97; P = 0.03; moderate certainty), which translated to 17.3 % (95 % CI 5, 26.8 %) absolute reduction in feeding intolerance. Prokinetics also reduced the risk of developing high gastric residual volumes (RR 0.69; 95 % CI 0.52, 0.91; P = 0.009; moderate quality) and increased the success of post-pyloric feeding tube placement (RR 1.60, 95 % CI 1.17, 2.21; P = 0.004; moderate quality). There was no significant improvement in the risk of vomiting, diarrhea, intensive care unit (ICU) length of stay or mortality. Prokinetic agents also did not significantly increase the rate of diarrhea.
CONCLUSION
There is moderate-quality evidence that prokinetic agents reduce feeding intolerance in critically ill patients compared to placebo or no intervention. However, the impact on other clinical outcomes such as pneumonia, mortality, and ICU length of stay is unclear.
Topics: Chi-Square Distribution; Critical Illness; Diarrhea; Domperidone; Dopamine Antagonists; Enteral Nutrition; Erythromycin; Gastric Emptying; Humans; Intensive Care Units; Length of Stay; Metoclopramide; Residual Volume; Vomiting
PubMed: 27527069
DOI: 10.1186/s13054-016-1441-z -
The Journal of Neuroscience : the... May 2022Emotion recognition abilities are fundamental to our everyday social interaction. A large number of clinical populations show impairments in this domain, with emotion...
Emotion recognition abilities are fundamental to our everyday social interaction. A large number of clinical populations show impairments in this domain, with emotion recognition atypicalities being particularly prevalent among disorders exhibiting a dopamine system disruption (e.g., Parkinson's disease). Although this suggests a role for dopamine in emotion recognition, studies employing dopamine manipulation in healthy volunteers have exhibited mixed neural findings and no behavioral modulation. Interestingly, while a dependence of dopaminergic drug effects on individual baseline dopamine function has been well established in other cognitive domains, the emotion recognition literature so far has failed to account for these possible interindividual differences. The present within-subjects study therefore tested the effects of the dopamine D2 antagonist haloperidol on emotion recognition from dynamic, whole-body stimuli while accounting for interindividual differences in baseline dopamine. A total of 33 healthy male and female adults rated emotional point-light walkers (PLWs) once after ingestion of 2.5 mg haloperidol and once after placebo. To evaluate potential mechanistic pathways of the dopaminergic modulation of emotion recognition, participants also performed motoric and counting-based indices of temporal processing. Confirming our hypotheses, effects of haloperidol on emotion recognition depended on baseline dopamine function, where individuals with low baseline dopamine showed enhanced, and those with high baseline dopamine decreased emotion recognition. Drug effects on emotion recognition were related to drug effects on movement-based and explicit timing mechanisms, indicating possible mediating effects of temporal processing. Results highlight the need for future studies to account for baseline dopamine and suggest putative mechanisms underlying the dopaminergic modulation of emotion recognition. A high prevalence of emotion recognition difficulties among clinical conditions where the dopamine system is affected suggests an involvement of dopamine in emotion recognition processes. However, previous psychopharmacological studies seeking to confirm this role in healthy volunteers thus far have failed to establish whether dopamine affects emotion recognition and lack mechanistic insights. The present study uncovered effects of dopamine on emotion recognition in healthy individuals by controlling for interindividual differences in baseline dopamine function and investigated potential mechanistic pathways via which dopamine may modulate emotion recognition. Our findings suggest that dopamine may influence emotion recognition via its effects on temporal processing, providing new directions for future research on typical and atypical emotion recognition.
Topics: Adult; Dopamine; Dopamine D2 Receptor Antagonists; Emotions; Female; Haloperidol; Humans; Male; Perception
PubMed: 35501156
DOI: 10.1523/JNEUROSCI.2364-21.2022 -
Brain Research Bulletin Apr 2023Stress contributes to pain sensation by affecting several neural pathways, including mesolimbic-cortical dopamine neurons. Nucleus accumbens, an essential element of the...
Stress contributes to pain sensation by affecting several neural pathways, including mesolimbic-cortical dopamine neurons. Nucleus accumbens, an essential element of the mesolimbic dopaminergic pathway, plays a fundamental role in modulating pain and is differentially influenced by stressful events. Since we previously demonstrated the marked association of intra-NAc dopamine receptors with forced swim stress-evoked analgesia in acute pain state, this research was conducted to consider the contribution of intra-accumbal D1- and D2-like dopamine receptors to modulating effects of exposure to restraint stress in pain-related behaviors during the tail-flick test. Stereotaxic surgery was executed to implant a guide cannula within the NAc in male Wistar rats. On the test day, different concentrations of SCH23390 and Sulpiride as D1- and D2-like dopamine receptor antagonists, respectively, were unilaterally microinjected within the NAc. The vehicle animals received saline or 12 % DMSO (0.5 µl) instead of SCH23390 or Sulpiride into the NAc, respectively. Five minutes following receiving drug or vehicle, animals were restrained for 3 h and then their acute nociceptive threshold was measured for a 60-min period by the tail-flick test. Our data revealed that RS considerably enhanced antinociceptive reaction in acute pain states. The analgesia evoked by RS dramatically declined following blocking either D1- or D2-like dopamine receptors in the NAc, an effect was more noticeable by D1-like dopamine receptor antagonist. These findings indicated that intra-NAc dopamine receptors are considerably mediated in the RS-produced analgesia in acute pain states, suggesting their possible role in psychological stress and disease.
Topics: Rats; Animals; Male; Sulpiride; Rats, Wistar; Acute Pain; Receptors, Dopamine D2; Receptors, Dopamine D1; Dopamine Antagonists; Nucleus Accumbens; Analgesics
PubMed: 36889361
DOI: 10.1016/j.brainresbull.2023.03.003