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1.
MSMR ; 31(1): 9-13, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38359359

ABSTRACT

The U.S. military has witnessed rising obesity among active component service members. The Department of Defense authorized coverage of weight loss medications in 2018, but no study has evaluated prescription prevalence within the active component. This descriptive retrospective cohort study analyzed data from active component U.S. military service members from January 2018 through June 2023. The study used data from the Defense Medical Surveillance System to determine prescription period prevalence of weight loss medication. Data on demographics, body mass index, and history of diabetes were considered. The study revealed a 100-fold increase in the prescription period prevalence of weight loss agents in the active component from their initial authorization date. Demographics associated with higher prescription period prevalence were non-Hispanic Black race and ethnicity, female sex, and older age. Service members in the health care occupations and the Navy had higher prevalence compared to other service branches and occupations. The findings indicate a significant rise in the period prevalence of weight loss prescriptions over time. Further research is recommended to assess the effectiveness, safety, and use in austere military environments.


Subject(s)
Anti-Obesity Agents , Military Personnel , Female , Humans , United States/epidemiology , Prevalence , Retrospective Studies , Anti-Obesity Agents/therapeutic use , Weight Loss
2.
Neuropharmacology ; 248: 109880, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38412888

ABSTRACT

Repurposing regulatory agency-approved molecules, with proven safety in humans, is an attractive option for developing new treatments for disease. We identified and assessed the efficacy of 3 drugs predicted by an in silico screen as having the potential to treat l-DOPA-induced dyskinesia (LID) in Parkinson's disease. We analysed ∼1.3 million Medline abstracts using natural language processing and ranked 3539 existing drugs based on predicted ability to reduce LID. 3 drugs from the top 5% of the 3539 candidates; lorcaserin, acamprosate and ganaxolone, were prioritized for preclinical testing based on i) having a novel mechanism of action, ii) having not been previously validated for the treatment of LID, iii) being blood-brain-barrier penetrant and orally bioavailable and iv) being clinical trial ready. We assessed the efficacy of acamprosate, ganaxolone and lorcaserin in a rodent model of l-DOPA-induced hyperactivity, with lorcaserin affording a 58% reduction in rotational asymmetry (P < 0.05) compared to vehicle. Acamprosate and ganaxolone failed to demonstrate efficacy. Lorcaserin, a 5HT2C agonist, was then further tested in MPTP lesioned dyskinetic macaques where it afforded an 82% reduction in LID (P < 0.05), unfortunately accompanied by a significant increase in parkinsonian disability. In conclusion, although our data do not support the repurposing of lorcaserin, acamprosate or ganaxolone per se for LID, we demonstrate value of an in silico approach to identify candidate molecules which, in combination with an in vivo screen, can facilitate clinical development decisions. The present study adds to a growing literature in support of this paradigm shifting approach in the repurposing pipeline.


Subject(s)
Dyskinesia, Drug-Induced , Levodopa , Humans , Animals , Levodopa/adverse effects , Artificial Intelligence , Drug Repositioning , Acamprosate/therapeutic use , Dyskinesia, Drug-Induced/drug therapy , Macaca , Antiparkinson Agents/adverse effects , Disease Models, Animal
3.
Drug Alcohol Depend ; 255: 111063, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38163425

ABSTRACT

BACKGROUND: Cocaine use disorder (CUD) is a major public health problem for which there is no approved pharmacotherapy. The primary purpose of this study was to evaluate the ability of lorcaserin, a 5-hydroxytryptamine2 C (5-HT2 C) receptor agonist, to facilitate abstinence in individuals seeking treatment for CUD. METHODS: This was a 12-site, randomized, parallel arm study with a 13-week Treatment Phase that included a 1-week, single-blind run-in period when all participants received twice daily 15mg acetazolamide capsules (a medication adherence marker), followed by randomization to either twice daily 10mg lorcaserin or placebo capsules for the remaining 12 weeks. Pre-randomization data were utilized in an enrichment strategy aimed at achieving high levels of medication adherence and low placebo response rates in a subgroup of participants that qualified for the "efficacy population." For lorcaserin vs. placebo, the primary efficacy endpoint was the proportion of participants in the efficacy population achieving abstinence during the last three weeks of treatment, as evidenced by self-report of no cocaine use, confirmed by urine testing. RESULTS: Within the efficacy population, 1.1% of 91 participants receiving lorcaserin and 4.3% of 92 receiving placebo achieved abstinence during the last 3 weeks of treatment. Among all randomized participants, 2.5% of 118 receiving lorcaserin and 5.6% of 124 receiving placebo achieved similar abstinence. Study participants receiving lorcaserin exhibited significantly greater reductions in body weight and BMI, indicating that medication adherence was sufficient to produce a pharmacological effect. CONCLUSIONS: Twice daily 10mg lorcaserin failed to demonstrate efficacy in the treatment of CUD.


Subject(s)
Benzazepines , Cocaine , Humans , Single-Blind Method , Body Weight , Benzazepines/pharmacology , Double-Blind Method , Treatment Outcome
4.
CNS Neurol Disord Drug Targets ; 23(3): 278-283, 2024.
Article in English | MEDLINE | ID: mdl-37005521

ABSTRACT

Lorcaserin is a 3-benzazepine that binds 5-HT2C serotonin receptors in the hypothalamus, where it mediates lack of hunger and/or satiety, and in the ventral tegmental area, the site of origin of the mesolimbic and mesocortical dopaminergic projections, which mediate pleasure and reward. The drug has been first developed for the treatment of obesity, where it has shown efficacy, and subsequently trialed to counter substance use (mostly cocaine, cannabis, opioids, and nicotine) and craving, but showed inconsistent effects. Since 2020, the US Food and Drug Administration obtained that the drug was voluntarily withdrawn from the US market on the grounds that its long-term use was found to be associated with a greater incidence of some types of cancer. Provided it can show to be free from cancerogenic effects, ongoing research suggests that lorcaserin may have therapeutic potential for a variety of disorders and conditions beyond obesity. Since 5-HT2C receptors are involved in many diversified physiological functions (mood, feeding, reproductive behavior, neuronal processes related to impulsiveness, and modulating reward-related mechanisms) this drug has the potential to treat different central nervous system conditions, such as depression and schizophrenia.


Subject(s)
Serotonin 5-HT2 Receptor Agonists , Serotonin , Humans , Serotonin 5-HT2 Receptor Agonists/therapeutic use , Benzazepines/pharmacology , Benzazepines/therapeutic use , Obesity/drug therapy
5.
Pharmacol Biochem Behav ; 234: 173673, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37951365

ABSTRACT

Lorcaserin, a selective serotonin 2C (5-HT2C) receptor agonist, was approved for treating obesity and has been investigated for treating substance use disorders including those involving opioids. Although lorcaserin was withdrawn from the market, interest in the therapeutic potential of drugs acting at 5-HT2C receptors continues, supporting the need to further characterize potential adverse effects especially when combined with drugs of abuse. This study examined acute effects of lorcaserin on opioid-induced ventilatory depression, which is the primary cause of overdose, and opioid self-administration, which models factors contributing to opioid abuse, in male and female rhesus monkeys. In one group (n = 4), effects of morphine (0.178 to 5.6 mg/kg, s.c.), fentanyl (0.0032 to 0.1 mg/kg, s.c.), and lorcaserin (0.1 to 1.78 mg/kg, s.c.) alone as well as effects of lorcaserin with each opioid on ventilation were determined using head plethysmography. Another group (n = 5) responded under a food versus fentanyl (0.1 to 3.2 µg/kg/infusion, i.v.) choice procedure, and lorcaserin (0.32 to 1.78 mg/kg, i.v.) was given as a pretreatment. Lorcaserin dose-dependently decreased minute volume to below 70 % of baseline when administered alone and increased the potency of morphine and fentanyl. Consistent with previous studies, lorcaserin failed to alter choice of fentanyl over food. This study demonstrates the novel finding that lorcaserin alone decreases ventilation and enhances the ventilatory-depressant effects of opioids. Taken together with previous studies, these results suggest that combining a 5-HT2C receptor agonist such as lorcaserin with an opioid could increase the risk of ventilatory depression without the benefit of decreasing abuse.


Subject(s)
Analgesics, Opioid , Respiratory Insufficiency , Male , Female , Humans , Analgesics, Opioid/adverse effects , Pharmaceutical Preparations , Serotonin , Benzazepines/pharmacology , Benzazepines/therapeutic use , Morphine , Fentanyl/adverse effects , Dose-Response Relationship, Drug
6.
Article in English | MEDLINE | ID: mdl-37641995

ABSTRACT

Obesity is a long-term lifestyle problem that can lead to disastrous consequences. Lifestyle interventions are one of the initial lines of management strategies for obesity but in long term, it is not very effective in the management of obesity. Some people also manage their weight with bariatric surgery, which is now the most effective obesity treatment. Synthetic pharmaceuticals make a bridge between lifestyle modification and bariatric surgery-based obesity management. The major problem associated with monotherapy without side effects is that these are moderately effective and also need in higher doses. The combination therapy is already used for many serious and complicated disease treatments and management and has shown efficacy as well. Generally, we use two or more medicines with different of actions for a better effect. The commonly used combination therapy for obesity management includes low-dose phentermine and prolonged and slow-releasing mechanism topiramate; naltrexone along with bupropion. Phentermine with inhibitors of Na-glucose cotransporter-2 or glucagon-like peptide-1 (GLP-1) agonist with gastric hormone or Na-glucose cotransporter-2 is two more viable combo therapy. This combination strategy aims to achieve success in the bariatric surgery and the scientific community is working in this direction.

7.
Behav Brain Res ; 447: 114438, 2023 06 05.
Article in English | MEDLINE | ID: mdl-37059187

ABSTRACT

Serotonin modulates many motivated behaviours via multiple receptor subtypes. Agonists at 5-HT2C receptors have potential for treating behavioural problems associated with obesity and drug use. In this work we examined the impact of the 5-HT2C receptor agonist lorcaserin on several motivated behaviours related to feeding, reward and waiting impulsivity, and on neuronal activation in key brain areas mediating those behaviours. In male C57BL/6J mice effects of lorcaserin (0.2, 1 and 5 mg/kg) were examined on feeding, and on operant responding for a palatable reward. Feeding was reduced only at 5 mg/kg, whereas operant responding was reduced at 1 mg/kg. At a much lower dose range lorcaserin 0.05-0.2 mg/kg also reduced impulsive behaviour measured as premature responding in the 5-choice serial reaction time (5-CSRT) test, without affecting attention or ability to perform the task. Lorcaserin induced Fos expression in brain regions related to feeding (paraventricular nucleus and arcuate nucleus), reward (ventral tegmental area), and impulsivity (medial prefrontal cortex, VTA) although these effects did not show the same differential sensitivity to lorcaserin as the behavioural measures. These results indicate a broad profile of action of 5-HT2C receptor stimulation on brain circuitry and on motivated behaviours, but with clear evidence of differential sensitivity across behavioural domains. This is exemplified by the fact that impulsive behaviour was reduced at a much lower dose range than was feeding behaviour. Along with previous work, and some clinical observations, this work supports the idea that 5-HT2C agonists may be useful for behavioural problems associated with impulsivity.


Subject(s)
Receptor, Serotonin, 5-HT2C , Serotonin , Animals , Male , Mice , Impulsive Behavior , Mice, Inbred C57BL , Reward , Serotonin/pharmacology , Serotonin 5-HT2 Receptor Agonists/pharmacology
8.
Adv Neurobiol ; 30: 195-206, 2023.
Article in English | MEDLINE | ID: mdl-36928851

ABSTRACT

Novel central nervous system (CNS)-based therapies have been difficult to produce due to the complexity of the brain, limited knowledge of CNS-based disease development and associated pathways, difficulty in penetrating the blood brain barrier, and a lack of reliable biomarkers of disease. Reverse engineering in drug development allows the utilization of new knowledge of disease pathways and the use of innovative technology to develop medications with enhanced efficacy and reduced toxicities. Lorcaserin was developed as a specific 5HT2C serotonin receptor agonist for the treatment of obesity with limited off-target effects at the 5HT2A and 5HT2B receptors. This receptor specificity limited the hallucinogenic and cardiovascular side effects noted with other serotonin receptor agonists. Reverse engineering approaches to drug development reduce the cost of producing new medications, identify specific populations of patients that will derive the most benefit from therapy, and produce novel therapies with greater efficacy and limited toxicity.


Subject(s)
Benzazepines , Drug Discovery , Serotonin Receptor Agonists , Humans , Benzazepines/therapeutic use , Brain/metabolism , Obesity , Serotonin Receptor Agonists/metabolism , Serotonin Receptor Agonists/therapeutic use , Drug Development/methods , Drug Discovery/methods
9.
J Clin Endocrinol Metab ; 108(9): 2262-2271, 2023 08 18.
Article in English | MEDLINE | ID: mdl-36897161

ABSTRACT

CONTEXT: Individual responses to weight loss (WL) medications vary widely and prediction of response remains elusive. OBJECTIVE: We investigated biomarkers associated with use of lorcaserin (LOR), a 5HT2cR agonist that targets proopiomelanocortin (POMC) neurons that regulate energy and glucose homeostasis, to identify predictors of clinical efficacy. METHODS: Thirty individuals with obesity were treated with 7 days of placebo and LOR in a randomized crossover study. Nineteen participants continued on LOR for 6 months. Cerebrospinal fluid (CSF) POMC peptide measurements were used to identify potential biomarkers that predict WL. Insulin, leptin, and food intake during a meal were also studied. RESULTS: LOR induced a significant decrease in CSF levels of the POMC prohormone and an increase in its processed peptide ß-endorphin after 7 days; ß-endorphin/POMC increased by 30% (P < .001). This was accompanied by a substantial decrease in insulin, glucose, and homeostasis model assessment of insulin resistance before WL. Changes in CSF POMC peptides persisted after WL (6.9%) at 6 months that were distinct from prior reports after diet alone. Changes in POMC, food intake, or other hormones did not predict WL. However, baseline CSF POMC correlated negatively with WL (P = .07) and a cutoff level of CSF POMC was identified that predicted more than 10% WL. CONCLUSION: Our results provide evidence that LOR affects the brain melanocortin system in humans and that effectiveness is increased in individuals with lower melanocortin activity. Furthermore, early changes in CSF POMC parallel WL-independent improvements in glycemic indexes. Thus, assessment of melanocortin activity could provide a way to personalize pharmacotherapy of obesity with 5HT2cR agonists.


Subject(s)
Pro-Opiomelanocortin , beta-Endorphin , Humans , Pro-Opiomelanocortin/cerebrospinal fluid , Cross-Over Studies , Obesity/drug therapy , Weight Loss , Melanocortins , Glucose , Insulin
10.
Mol Metab ; 68: 101665, 2023 02.
Article in English | MEDLINE | ID: mdl-36592795

ABSTRACT

OBJECTIVE: Overweight and obesity are endemic in developed countries, with a substantial negative impact on human health. Medications developed to treat obesity include agonists for the G-protein coupled receptors glucagon-like peptide-1 (GLP-1R; e.g. liraglutide), serotonin 2C (5-HT2CR; e.g, lorcaserin), and melanocortin4 (MC4R) which reduce body weight primarily by suppressing food intake. However, the mechanisms underlying the therapeutic food intake suppressive effects are still being defined and were investigated here. METHODS: We profiled PPG neurons in the nucleus of the solitary tract (PPGNTS) using single nucleus RNA sequencing (Nuc-Seq) and histochemistry. We next examined the requirement of PPGNTS neurons for obesity medication effects on food intake by virally ablating PPGNTS neurons. Finally, we assessed the effects on food intake of the combination of liraglutide and lorcaserin. RESULTS: We found that 5-HT2CRs, but not GLP-1Rs or MC4Rs, were widespread in PPGNTS clusters and that lorcaserin significantly activated PPGNTS neurons. Accordingly, ablation of PPGNTS neurons prevented the reduction of food intake by lorcaserin but not MC4R agonist melanotan-II, demonstrating the functional significance of PPGNTS 5-HT2CR expression. Finally, the combination of lorcaserin with GLP-1R agonists liraglutide or exendin-4 produced greater food intake reduction as compared to either monotherapy. CONCLUSIONS: These findings identify a necessary mechanism through which obesity medication lorcaserin produces its therapeutic benefit, namely brainstem PPGNTS neurons. Moreover, these data reveal a strategy to augment the therapeutic profile of the current frontline treatment for obesity, GLP-1R agonists, via coadministration with 5-HT2CR agonists.


Subject(s)
Glucagon-Like Peptide 1 , Liraglutide , Humans , Glucagon-Like Peptide 1/pharmacology , Glucagon-Like Peptide 1/metabolism , Liraglutide/pharmacology , Liraglutide/therapeutic use , Glucagon-Like Peptide-1 Receptor/metabolism , Serotonin/metabolism , Appetite , Obesity/drug therapy , Obesity/metabolism , Solitary Nucleus/metabolism , Eating , Neurons/metabolism
11.
Chinese Pharmacological Bulletin ; (12): 993-997, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1013949

ABSTRACT

Aim To develop an UPLC-MS/MS method to determine the concentration of lorcaserin hydrochloride in beagle plasma, and study the pharmacokinetics of osmotic pump controlled-release tablets of lorcaserin hydrochloride. Methods A randomized crossover design was used, carbamazepine as the internal standard(IS), and plasma protein precipitation with acetonitrile. The chromatographic was Phenomenex Polar C18 column(100 mm×2. 1 mm, 3 μm), and acetonitrile - water(containing 10 mmol·L-1 ammonium acetate and 0.1% formic acid)(40:60, V/V)was mobile phase. Multiple reaction monitoring mode and electrospray positive ionization were used to detect lorcaserin hydrochloride. The MS/MS ion transitions were monitored at m/z 196.2→129.2 for lorcaserin hydrochloride and m/z 237→194.1 for carbamazepine, respectively. Results The linear range was 1 to 500 μg·L-1(r=0.999 2), the extraction recovery rate ranged from 87.70% to 89.70%, the precision RSD was 9.7%. The accuracy and matrix effect met the requirements, and the stability of lorcaserin hydrochloride was good in -20 ℃ refrigerator for 45 d, repeated freezing and thawing for three times, placed at room temperature for 24 h, and the disposed samples placed in automatsampler for 6 h were stable. The main pharmacokinetic parameters of the controlled-release tablet and immediate-release tablet were as follows:Tmax was(8.00±1.27)h and(1.00±0.13)h, Cmax was(70.56±3.73)μg·L-1 and(176.33±16.73)μg·L-1, and AUC0-t was(966.33±7.56)μg·h·L-1 and(973.05±69.09)μg·h·L-1, respectively. Conclusions The established UPLC-MS/MS method can be used to study the pharmacokinetics of lorcaserin hydrochloride in the plasma of beagle dogs, and osmotic pump controlled-release tablets has sustained release effect.

12.
Mayo Clin Proc Innov Qual Outcomes ; 6(5): 465-474, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36160639

ABSTRACT

Objective: To evaluate the safety and effectiveness of combination varenicline with lorcaserin in preventing post-cessation weight gain. Participants and Methods: We conducted a randomized (varenicline for 12 weeks + lorcaserin for 24 weeks vs varenicline for 12 weeks + placebo for 24 weeks) phase II clinical study to obtain preliminary data on the safety and effectiveness of combination varenicline and lorcaserin in preventing post-cessation weight gain in overweight and obese smokers. Eighty-four overweight and obese (body mass index [BMI], 27-40 kg/m2) cigarette smokers were randomized before study termination (lorcaserin: n=40; placebo: n=44). The primary outcomes were weight and waist circumference (WC) changes at 12 and 24 weeks in smokers meeting criteria for prolonged smoking abstinence. Results: Thirty-nine participants met criteria for prolonged smoking abstinence at 12 weeks (46%) and 21 at 24 weeks (25%). No significant treatment effect was observed at 12 weeks with lorcaserin compared with placebo (weight difference, -0.7 kg; 90% CI, -2.6 to 1.1 kg; P=.51; WC difference, -1.9 cm; 90% CI, -4.2 to 0.5 cm; P=.18; or BMI difference, -0.4 kg/m2; 90% CI, -1.1 to 0.3 kg/m2; P=.33). No significant treatment effect was observed between lorcaserin at 24 weeks compared with placebo (weight, 1.4 kg; 90% CI, -3.8 to 6.7 kg; P=.65; WC, -0.9 cm; 90% CI, -5.8 to 4.0 cm; P=.75; or BMI 0.29 kg/m2; 90% CI, -1.5 to 2.12 kg/m2; P=.79). Conclusion: Weight gain and WC increases after prolonged smoking abstinence were not reduced using combination varenicline and lorcaserin. The results do not support further research in the obese and weight-concerned smoking population using lorcaserin or similar drugs. Trial Registration: clinicaltrials.gov Identifier: NCT02412631.

13.
Front Endocrinol (Lausanne) ; 13: 984041, 2022.
Article in English | MEDLINE | ID: mdl-36120448

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) is the commonest chronic liver disease and affects a considerable proportion of the general population worldwide. Obesity is a major risk factor for development and progression of NAFLD and weight loss is an effective intervention for the management of NAFLD. However, few patients achieve substantial and sustained weight loss with lifestyle measures. Therefore, antiobesity agents are frequently considered in patients with NAFLD but there are limited data on their safety and efficacy. In the present review, we discuss the role of antiobesity agents in the management of NAFLD. All approved antiobesity agents appear to reduce transaminase levels and to improve steatosis in patients with NAFLD. However, their effects on fibrosis are less well studied and whether they affect liver-related outcomes, including progression to cirrhosis and hepatocellular cancer, is unknown. The glucagon-like peptide-1 receptor agonists, liraglutide and semaglutide, appear to represent a first-line option in obese patients with NAFLD and type 2 diabetes mellitus (T2DM) since they induce considerable weight loss and have been extensively studied in patients with T2DM. However, more studies are needed to evaluated their effects on liver-related and cardiovascular outcomes in patients with NAFLD, particularly in those without T2DM.


Subject(s)
Anti-Obesity Agents , Diabetes Mellitus, Type 2 , Non-alcoholic Fatty Liver Disease , Anti-Obesity Agents/therapeutic use , Diabetes Mellitus, Type 2/epidemiology , Glucagon-Like Peptide-1 Receptor , Humans , Liraglutide , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/epidemiology , Obesity/complications , Obesity/drug therapy , Platelet Aggregation Inhibitors , Transaminases , Weight Loss
14.
Cell Rep ; 40(7): 111211, 2022 08 16.
Article in English | MEDLINE | ID: mdl-35977511

ABSTRACT

RNA editing is a process by which post-transcriptional changes of mRNA nucleotides alter protein function through modification of the amino acid content. The 5HT2C serotonin receptor, which undergoes 32 distinct RNA-editing events leading to 24 protein isoforms, is a notable example of this process. These 5HT2C isoforms display differences in constitutive activity, agonist/inverse agonist potencies, and efficacies. To elucidate the molecular mechanisms responsible for these effects of RNA editing, we present four active-state 5HT2C-transducer-coupled structures of three representative isoforms (INI, VGV, and VSV) with the selective drug lorcaserin (Belviq) and the classic psychedelic psilocin. We also provide a comprehensive analysis of agonist activation and constitutive activity across all 24 protein isoforms. Collectively, these findings reveal a unique hydrogen-bonding network located on intracellular loop 2 that is subject to RNA editing, which differentially affects GPCR constitutive and agonist signaling activities.


Subject(s)
RNA Editing , Receptors, Serotonin , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, Serotonin/metabolism , Signal Transduction/genetics
15.
Neuropharmacology ; 215: 109150, 2022 09 01.
Article in English | MEDLINE | ID: mdl-35644487

ABSTRACT

The neurotransmitter serotonin (5-hydroxytryptamine; 5-HT) modulates fundamental motivational processes, and the neurochemical and behavioural effects of drugs of abuse. Recently, attention has focused on the role of 5-HT acting via 5-HT2A and 5-HT2C receptor sub-types in this regard. We examined the impact of manipulating 5-HT2A and 5-HT2C receptor mediated function on several aspects of alcohol self-administration and alcohol-seeking behaviour in male and female rats. Specifically, experiments investigated the effect of the 5-HT2A inverse agonist/antagonist pimavanserin, and the 5-HT2C receptor agonist lorcaserin on these behaviours. In male and female rats trained to respond for alcohol reinforcement on fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement pimavanserin (0.3, 1 and 3 mg/kg) had no consistent effect on responding. Lorcaserin (0.25, 0.5 and 1 mg/kg) reduced these behaviours in both sexes. Following extinction of responding for alcohol, alcohol-seeking was reinstated by cues previously paired with alcohol. Pimavanserin (1 mg/kg) and lorcaserin (0.5 mg/kg) significantly reduced this reinstatement. In a two-bottle 24 h intermittent access procedure pimavanserin had no significant effects, but lorcaserin reduced alcohol consumption in both sexes at 1, 4 and 24 h after access to alcohol was allowed. Finally, as determined using in vivo microdialysis, alcohol increased, and lorcaserin (0.5 mg/kg) reduced, extracellular levels of DA in the NAc in male rats. In rats treated with lorcaserin prior to alcohol injection the net effect was that DA levels were not changed compared to those measured in control rats. These results suggest that blocking 5-HT2A receptor activity has a very limited action to reduce alcohol-seeking. Activating 5-HT2C receptors had a broader behavioural profile to reduce alcohol self-administration, alcohol drinking and alcohol seeking. These effects may partly result from a blunting of the effect of alcohol on mesolimbic DA release.


Subject(s)
Serotonin 5-HT2 Receptor Agonists , Serotonin , Animals , Benzazepines , Dose-Response Relationship, Drug , Female , Male , Piperidines , Rats , Receptor, Serotonin, 5-HT2C , Self Administration , Serotonin 5-HT2 Receptor Agonists/pharmacology , Urea/analogs & derivatives
16.
Metabolism ; 133: 155237, 2022 08.
Article in English | MEDLINE | ID: mdl-35700837

ABSTRACT

BACKGROUND: Growth differentiation factor 15 (GDF-15) is a stress-response cytokine proposed to be associated with body weight regulation. AIMS: The primary aim was to investigate changes of circulating intact GDF-15 (wildtype, non-carrier of the rs1058587 polymorphism coding for the H2O2D mutation) and total GDF-15 (measured irrespective of the mutation) in response to liraglutide (GLP-1 receptor agonist) and lorcaserin (5-HT2C receptor agonist), two pharmacologic agents that induce food intake and weight reduction. In addition, we perform exploratory correlations of total and intact GDF-15 with clinical, hormonal and metabolo-lipidomic parameters in humans with obesity. MATERIALS AND METHODS: We utilized two studies: 1) Study 1, a randomized, double-blinded, cross-over trial of liraglutide and placebo administration for 5 weeks in subjects with obesity (n = 20; BMI = 35.6 ± 5.9 kg/m2), in escalating doses starting at 0.6 mg/day on week 1 and increased every week, up to the highest dose of 3.0 mg/day during week 5. b) Study 2, a randomized, double-blinded trial of lorcaserin 10 mg twice daily, or placebo for 12-weeks in humans with obesity (n = 34 BMI = 37.4 ± 6.1 kg/m2). Total and intact GDF-15 levels were measured with novel enzyme-linked immunosorbent assays and the metabolomics and lipidomics analysis was performed with nuclear magnetic resonance spectroscopy. RESULTS: Total and intact GDF-15 were positively correlated with diabetes risk index and trimethylamine N-oxide and negatively with eGFR. Despite significant changes in body weight, total and intact GDF-15 were not altered in response to liraglutide or lorcaserin treatment in subjects with obesity. CONCLUSIONS: Total and intact GDF-15 levels are not altered in response to liraglutide or lorcaserin therapy and are thus not directly involved in the metabolic feedback loop pathways downstream of GLP1 or 5-HT2C receptor agonists. Since neither total nor intact GDF-15 levels were altered in response to weight loss, future studies are needed to elucidate the pathways activated by GDF-15 in humans and its role, if any, in body weight regulation and energy homeostasis.


Subject(s)
Benzazepines , Growth Differentiation Factor 15 , Liraglutide , Obesity , Benzazepines/administration & dosage , Body Weight , Double-Blind Method , Growth Differentiation Factor 15/blood , Humans , Liraglutide/administration & dosage , Obesity/blood , Obesity/drug therapy , Receptor, Serotonin, 5-HT2C/metabolism , Serotonin 5-HT2 Receptor Agonists/administration & dosage , Weight Loss
17.
Pharmacol Res Perspect ; 10(3): e00947, 2022 06.
Article in English | MEDLINE | ID: mdl-35599337

ABSTRACT

The prolonged exposure to obesogenic diets disrupts the mesocortical dopaminergic input to the prefrontal cortex (PFC). This leads to suboptimal dopamine levels in this brain region, which affects cognition and control of food intake. Treatments that restore mesocortical dopaminergic neurotransmission may improve obesity-associated cognitive dysfunction and modulate food intake to induce weight loss. Given the complexity and multifactorial nature of obesity, combination treatments would likely achieve sizeable and sustained body weight loss and improve obesity-linked outcomes, such as cognitive dysfunction. Given this background, we hypothesize that concomitant activation of serotonin 5-HT2C and histamine H1 receptors, coupled with antagonism of histamine H3 receptors, synergistically modulates mesocortical dopamine neurotransmission and ameliorates obesity-induced cognitive dysfunction. We propose to test the hypothesis in a diet-induced obesity (DIO) rat model by treating animals with the 5-HT2C agonist lorcaserin and the H1 agonist and H3 antagonist betahistine. Consistent with our hypothesis, both lorcaserin and betahistine have been shown to reduce body weight in humans with obesity and animals. Both drugs have been demonstrated to improve cognitive functions by influencing dopaminergic signaling in the PFC. The proposed combination treatment addresses the paucity of studies on obesity treatments that improve cognitive function. This research may also help identify a potential targetable mechanism connecting obesity and neurocognitive outcomes.


Subject(s)
Betahistine , Cognitive Dysfunction , Animals , Benzazepines , Betahistine/pharmacology , Betahistine/therapeutic use , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/etiology , Dopamine , Obesity/complications , Obesity/drug therapy , Rats , Rats, Sprague-Dawley
18.
Chem Pharm Bull (Tokyo) ; 70(3): 202-210, 2022.
Article in English | MEDLINE | ID: mdl-35228384

ABSTRACT

Long-term and constant-release osmotic-pump lorcaserin hydrochloride controlled-release tablets (OP LH CRTs) were prepared, to investigate the influencing factors of LH release and optimize the formulation. The mechanism of release of LH from OP LH CRTs in vitro was investigated. By establishing a high-efficiency method for measuring LH release in vitro, and optimizing it by single-factor and orthogonal experiments, the best formulation of OP LH CRTs was determined. Then, the optimal prescription of OP LH CRTs was: LH = 20.8 mg; mannitol = 100 mg, microcrystalline cellulose = 125 mg; magnesium stearate = 5 mg; cellulose acetate = 3%; polyethylene glycol 400 = 10%; dibutyl phthalate = 10%; Wetting agent and binder was 3% polyvinyl pyrrolidone (PVP) K30 ethanol solution; aperture diameter = 0.8 mm; the coating gained 3% weight. And finally, prepared OP LH CRTs were released at a constant rate in vitro and sustained for 16 h with good reproducibility between batches. Using an orthogonal experimental design, OP LH CRTs with remarkable zero-order release characteristics within 16 h were obtained, and formulation optimization was realized.


Subject(s)
Delayed-Action Preparations , Benzazepines , Delayed-Action Preparations/chemistry , Reproducibility of Results , Solubility , Tablets
19.
Expert Opin Emerg Drugs ; 27(1): 75-90, 2022 03.
Article in English | MEDLINE | ID: mdl-35341431

ABSTRACT

INTRODUCTION: Despite the existence of over 30 anti-seizure medications (ASM), including 20 over the last 30 years, a third of patients with epilepsy remain refractory to treatment, with no disease-modifying or preventive therapies until very recently. The development of new ASMs with new mechanisms of action is therefore critical. Recent clinical trials of new treatments have shifted focus from traditional common epilepsies to rare, genetic epilepsies with known mechanistic targets for treatment and disease-specific animal models. AREAS COVERED: ASMs in phase 2a/b-3 clinical trials target cholesterol, serotonin, sigma-1 receptors, potassium channels and metabotropic glutamate receptors. Neuroinflammation, protein misfolding, abnormal thalamocortical firing, and molecular deficiencies are among the targeted pathways. Clinically, the current phase 2a/b-3 agents hold promise for variety of epilepsy conditions, from developmental epileptic encephalopathies (Dravet Syndrome, Lennox-Gastaut syndrome, CDKL5 and PCDH19, Rett's Syndrome), infantile spasms, tuberous sclerosis as well as focal and idiopathic generalized epilepsies and acute rescue therapy for cluster seizures. EXPERT OPINION: New delivery mechanisms increase potency and site-specificity of existing drugs. Novel mechanisms of action involve cholesterol degradation, mitochondrial pathways, anti-inflammation, and neuro-regeneration. Earlier identification of genetic conditions through genetic testing will allow for earlier use of disease specific and disease-modifying therapies.


Subject(s)
Anticonvulsants , Epilepsy , Animals , Clinical Trials, Phase II as Topic , Clinical Trials, Phase III as Topic , Epilepsy/drug therapy , Epilepsy/genetics , Expert Testimony , Humans
20.
Adv Pharmacol ; 93: 219-242, 2022.
Article in English | MEDLINE | ID: mdl-35341567

ABSTRACT

Substance use disorders (SUD) develop as a result of complex interactions between the environment, the subject, and the drug of abuse. Preclinical basic research investigating each of these tripartite components of SUD individually has resulted in advancements in our fundamental knowledge regarding the progression from drug abuse to SUD and severe drug addiction and the underlying behavioral and neurobiological mechanisms. How these complex interactions between the environment, the subject, and the drug of abuse impact the effectiveness of candidate or clinically used medications for SUD has not been as extensively investigated. The focus of this chapter will address the current state of our knowledge how these environmental, subject, and pharmacological variables have been shown to impact candidate or clinical SUD medication evaluation in preclinical research using drug self-administration procedures as the primary dependent measure. The results discussed in this chapter highlight the importance of considering environmental variables such as the schedule of reinforcement, concurrent availability of alternative nondrug reinforcers, and experimental housing conditions in the context of SUD therapeutic evaluation. The thesis of this chapter is that improved understanding of environmental variables in the context of SUD research will facilitate the utility of preclinical drug self-administration studies in the evaluation and development of candidate SUD therapeutics.


Subject(s)
Substance-Related Disorders , Humans , Substance-Related Disorders/drug therapy
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