Behavioral tests in mice and other animals are widely used to study anxiety and to evaluate the efficacy of anxiolytic compounds. However, the validity of behavioral tests used to assess anxiety-like behavior has been questioned because their results are often inconsistent and not readily replicated across studies. We developed a simple falling-trap test to examine whether the number of falls could serve as an index of anxiety-like behavior. The test is designed to produce falls from an elevated path, based on the hypothesis that less-anxious mice would be more prone to fall. Male C57BL/6N mice were given vehicle or chlordiazepoxide (CDP), and their behavior was evaluated using both the novel test and the elevated plus maze (EPM). The outcomes were the number of falls in the falling-trap test and open-arm time in the EPM. In the falling-trap test, CDP-treated mice did not show a statistically significant increase in the number of falls compared with control mice. In contrast, CDP significantly increased open-arm time in the EPM. Thus, under the present experimental conditions, these findings did not support the hypothesis that the number of falls in the falling-trap test could serve as a measure of anxiety-like behavior. Further studies are needed to determine the conditions under which this assay could be useful and to establish its reliability and validity.

Nearly 100 years ago, Ivan Pavlov's research into learning processes provided a framework for understanding how the brain makes behaviorally impactful associations between events. His seminal findings on excitatory and inhibitory conditioning established the scientific and conceptual foundation for the later discovery of Pavlovian occasion setting. That is, a higher-order association that modulates whether or not a conditioned stimulus will evoke a conditioned response-feature positive and feature negative occasion setters, respectively. While much of this research has used exteroceptive stimuli (tone, lights), interoceptive stimuli (intoxication, hunger) can also acquire occasion setting functions. Research using the drug discriminated goal-tracking (DDGT) task demonstrates that interoceptive drug stimuli serve reliably as occasion setters. A wide range of drug stimuli across pharmacological classes function as occasion setters (e.g., nicotine, chlordiazepoxide, morphine) in the DDGT task. Moreover, interoceptive drug occasion setters exhibit similar characteristics as exteroceptive occasion setters. These include resistance to simple extinction procedures, generalization across stimulus (drug) class with shared function as an occasion setters, and a drug feature-negative occasion setter acquiring conditioned inhibitory effects. We explore future avenues of inquiry utilizing the DDGT task to expand our understanding of occasion setting. We highlight methodological strengths that recommend the DDGT task for probing the neuropharmacological and neuroanatomical mechanisms of drug occasion setters. Pavlov recognized the importance of interoception, and the role conditioning processes play in health and well-being. We invite readers to consider how their research intersects with the topic of interoceptive conditioning. By working together, we can build our understanding of basic interoceptive Pavlovian conditioning processes and realize the solutions this knowledge holds to societal issues.

Brucellosis is a globally important zoonotic disease caused by Brucella melitensis, the most virulent and clinically significant species affecting both humans and livestock. Unlike many Gram-negative pathogens, B. melitensis lacks conventional virulence factors and instead relies on specialized systems such as the Type IV Secretion System (T4SS) for the secretion of effector proteins. In this study, an integrated computational pipeline was implemented to identify, model, and assemble the T4SS components encoded by virB operon from the complete B. melitensis proteome. Template-based modeling strategies were employed to model T4SS subcomplexes, referencing crystallographic data from E. coli T4SS. Structural superposition with E. coli homologues revealed highly conserved architecture despite only 30-50% sequence identity. Stereochemical validation confirmed favorable interactions among most VirB protein pairs, and membrane insertion analysis corroborated the spatial orientation of the modeled T4SS. Potential of T4SS as a drug target was explored by targeting dimeric interface of VirB11 ATPase to disrupt protein-protein interactions. Virtual screening of compounds from DrugBank revealed compounds with docking score ≤-7.0 kcal/mol, and ADMET screening yielded three promising candidates─Ezetimibe (Drug ID: DB00973), Chlordiazepoxide (Drug ID: DB00475), and Alloin (Drug ID: DB15477). MM-GBSA analysis and molecular dynamics simulation supported favorable protein-ligand interactions. Collectively, these findings provide new insights into the architecture of B. melitensis T4SS and identify three potential drug molecules targeting T4SS. This supports FDA-approved drug repurposing as an effective strategy for antivirulence therapy against Brucellosis.

Risky choice is a defining feature of many psychological disorders and maladaptive behavior. There is evidence that benzodiazepines, a class of drugs that act on the GABA system, may increase risky choice. Long-term use of these medications is common, but relatively little is known about how repeated/chronic use of benzodiazepines affects risky decision making. The present study examined effects of acute and repeated chlordiazepoxide, a prototypic benzodiazepine, on probability discounting in eight male Sprague-Dawley rats. The probability-discounting task involved choices between a single food pellet with guaranteed delivery and three food pellets with decreasing probabilities of delivery across each experimental session. Risky choice was operationally defined as choice for the larger, uncertain reinforcer over the smaller, certain reinforcer. During baseline, responding was sensitive to the programmed contingencies, and larger-reinforcer choice decreased as the probability of delivery decreased. Acute administration of chlordiazepoxide (1.0-30.0 mg/kg) dose-dependently increased risky choice and trial omissions. Tolerance to chlordiazepoxide's effects on these outcomes was observed after repeated 10.0 mg/kg administration. The results of the present study indicate that acute chlordiazepoxide can increase risky choice in a probability-discounting task and that tolerance to this effect develops after chronic exposure to the drug. Limitations of the present study are discussed, as are directions for future research on benzodiazepines and risky choice.

Alcohol dependence (AD) is associated with several physical and psychiatric implications such as those observed in alcohol withdrawal syndrome (AWS) and AD with co-morbid anxiety. With the increasing burden of AD in India, both physicians and psychiatrists face unique challenges while managing patients with AWS, AD, and AD with anxiety. Physicians are often the first point of contact for patients presenting with alcohol use-related medical complications but lack clear management directives that distinguish their role from that of psychiatrists. To address this need gap, a series of five focus group discussions were conducted with a total of 57 expert physicians and psychiatrists. The expert opinions are presented along with supporting evidence from current literature based on a comprehensive literature review. This practice and policy review presents guidance for physicians and psychiatrists on the optimal screening, diagnosis, and treatment pathways to follow for patients presenting with each of the three indications. It highlights the importance of accurately diagnosing and distinguishing the three indications by using distinct inventories of presenting symptoms, questions to be asked as a part of comprehensive history-taking of the patient, screening questionnaires and tools, and laboratory investigations. It also discusses the roles of different classes of drugs in addressing the diverse presentations and comorbidities associated with each indication. Benzodiazepines, especially long-acting ones like chlordiazepoxide, remain the mainstay for detoxification protocols for both AWS and AD. Physicians need to work in conjunction with psychiatrists and refer the patient when required, based on distinct criteria such as severity of psychiatric comorbidities, complications of withdrawal, and behavioral issues leading to persistent alcohol use and relapses. The application of this holistic management approach that encompasses the multifaceted nature of alcohol-use related disorders will help reduce relapse rates and ensure optimal patient outcomes.

Background: Multiple sclerosis (MS) is a neuroinflammatory disease characterized by autoimmune-driven inflammation in the central nervous system that damages axons and destroys myelin. It is difficult to diagnose multiple sclerosis due to its complexity, and different people may react differently to different treatments. While the exact cause of multiple sclerosis (MS) and the reasons for its increasing prevalence remain unclear, it is widely believed that a combination of genetic predisposition and environmental influences plays a significant role. Methods: Finding biomarkers for complicated diseases like multiple sclerosis (MS) is made more promising by the emergence of network and system biology technologies. Currently, using tools like Network Analyst to apply network-based gene expression profiling provides a novel approach to finding potential medication targets followed by molecular docking and MD Simulations. Results: There were 1200 genes found to be differentially expressed, with CD44 showing the highest degree score of 15, followed by CDC42 and SNAP25 genes, each with a degree score of 14. To explore the regulatory kinases involved in the protein-protein interaction network, we utilized the X2K online tool. The present study examines the binding interactions and the dynamic stability of four ligands (Obeticholic acid, Chlordiazepoxide, Dextromethorphan, and Hyaluronic acid) in the Hyaluronan binding site of the human CD44 receptor using molecular docking and molecular dynamics (MD) simulations. Docking studies demonstrated a significant docking score for Obeticholic acid (-6.3 kcal/mol), underscoring its medicinal potential. MD simulations conducted over a 100 ns period corroborated these results, revealing negligible structural aberrations (RMSD 1.3 Å) and consistent residue flexibility (RMSF 0.7 Å). Comparative examinations of RMSD, RMSF, Rg, and β-factor indicated that Obeticholic acid exhibited enhanced stability and compactness, establishing it as the most promising choice. Conclusions: This integrated method underscores the significance of dynamic validations for dependable drug design aimed at CD44 receptor-mediated pathways. Future experimental techniques are anticipated to further hone these findings, which further advance our understanding of putative biomarkers in multiple sclerosis (MS).

Clinicians have prescribed benzodiazepines for a range of symptoms and conditions since the Food and Drug Administration approved chlordiazepoxide in 1960. Between 1969 and 1982, the benzodiazepine diazepam was the most prescribed medication in the United States. Since then, recognition of benzodiazepine's risks-such as falls, psychomotor and cognitive impairment, withdrawal, benzodiazepine use disorder (BzUD), and suicidality-and limited data on long-term safety and efficacy have created challenges for clinicians and patients, including when and how to safely taper these medications. In 2025, 10 professional societies, including the American Society of Addiction Medicine (ASAM), released the Joint Clinical Practice Guideline on Benzodiazepine Tapering. This commentary explores implications for addiction treatment.

Monoamine oxidase inhibitors (MAOIs) remain an important option for patients with treatment-resistant depression (TRD) and other psychiatric conditions, despite potentially serious drug-drug interactions and associated dietary tyramine restrictions. However, they are rarely prescribed in patients with comorbid substance use disorders (SUDs) due to concerns about potential drug interactions and limited research in these populations. This narrative review investigates the use of MAOIs in patients who use psychoactive substances, exploring potential interactions while summarizing the relatively scant literature on using MAOIs as treatments for SUDs. It synthesizes data from 219 peer-reviewed publications investigating MAOI/psychoactive substance interactions or the use of MAOIs to treat SUDs or psychiatric conditions in patients with comorbid SUDs, including 20 randomized controlled trials, 18 non-randomized interventional trials, 32 observational studies/case series, 56 case reports, 85 preclinical studies, and 8 reviews, with publication years spanning from 1955 to 2025. Data from 28 non-peer-reviewed user-submitted reports from drug use/harm reduction forums are also included. Suspected cases of serotonin toxicity have been reported for MAOIs in combination with amphetamine, dextromethorphan, 3,4-methylenedioxymethamphetamine (MDMA), meperidine (pethidine), methadone, and tramadol. Hypertensive urgency/emergency has been reported for MAOIs in combination with alcohol (varieties containing significant amounts of tyramine), amphetamine, cocaine, dextroamphetamine, khat, methamphetamine, and psilocybin mushrooms. Other notable adverse events associated with MAOIs in combination with psychoactive substances include agitation (4-bromo-2,5-dimethoxyphenethylamine [2C-B] 5-methoxy-N,N-dimethyltryptamine [5-Meo-DMT]), N,N-dimethyltryptamine [DMT]), delirium/confusion (DMT, propoxyphene, and tramadol), edema (chlordiazepoxide), intracranial hemorrhage (amphetamine, khat, and methamphetamine), mania/psychosis (DMT), rhabdomyolysis (5-MeO-DMT, DMT, and propoxyphene), and sedation/stupor/loss of consciousness (amobarbital, amphetamine, cocaine, dextroamphetamine, and propoxyphene). Fatalities have been reported for MAOIs in combination with 5-MeO-DMT, amphetamine, dextroamphetamine, dextromethorphan (in overdose), MDMA, methamphetamine, meperidine, and tramadol (in overdose). Based on our findings, some substances, such as alcoholic beverages containing significant tyramine quantities (uncommon today), amphetamines, opioids with significant serotonergic reuptake inhibition, and some hallucinogens such as the empathogen/entactogen MDMA, can pose potentially fatal risks in combination with MAOIs. However, MAOI treatment of patients who use alcoholic beverages low in tyramine, caffeine, cannabis, nicotine, sedatives, some (primarily classic) hallucinogens, and some other substances can likely be appropriately managed with careful monitoring, although psychoactive substance dose and route of administration are important safety considerations. While there was initially hope MAOIs might effectively treat some SUDs, there are no robust human data to support their efficacy in this context. Given growing levels of substance use and an increasing number of novel illicit compounds being produced, more research on MAOI safety in patients with psychiatric conditions and comorbid psychoactive substance use/misuse is essential to determining their appropriateness in this complex patient population.