Cluster analysis in gambling disorder based on sociodemographic, neuropsychological, and neuroendocrine features regulating energy homeostasis

Comparing efficacy of serotonergic, opioidergic, and glutamatergic drugs in gambling disorder: A pooled analysis of response trajectories versus placebo

Various pharmacological treatments have been explored to alleviate the symptoms and clinical manifestations of gambling disorder (GD) by targeting different neurotransmitter systems. This study retrospectively analyzed subjects with GD treated with serotonergic drugs, opioid antagonist drugs, and glutamatergic drugs compared to placebo, through a pooled analysis of clinical trials conducted at the University of Chicago. The Gambling Symptom Assessment Scale (G-SAS) was employed as the outcome measure. Temporal uniformity was ensured by managing timepoints as follows: baseline, early (4-5 weeks), intermediate (6-8 weeks), and final (10-16 weeks) from the start of treatment. A total of 253 treatment-seeking subjects were included, receiving either glutamatergic drugs (N-acetylcysteine, memantine), opioidergic drugs (naltrexone), serotonergic drugs (paroxetine, escitalopram), or placebo. Within-group analysis demonstrated significant improvement in GD symptoms across all treatment groups. When comparing interventions over time, glutamatergic drugs proved more effective than placebo from the early observation timepoint and onwards. Opioidergic drugs were more effective than placebo at the final observation timepoint, while serotonergic drugs showed no significant effect compared to placebo. Our findings reveal distinct efficacy patterns among the pharmacological classes, likely due to their different mechanisms of action and the various aspects of GD phenomenology they address. The significant placebo effect observed aligns with previous studies, underscoring the complexity of treating GD. In conclusion, given the heterogeneous nature of GD, these results emphasize the necessity of identifying and precisely characterizing GD subtypes to facilitate more tailored treatment approaches.

Peptide with Dual Roles in Immune and Metabolic Regulation: Liver-Expressed Antimicrobial Peptide-2 (LEAP-2)

Liver-expressed antimicrobial peptide 2 (LEAP-2) was originally discovered as an antimicrobial peptide that plays a vital role in the host innate immune system of various vertebrates. Recent research discovered LEAP-2 as an endogenous antagonist and inverse agonist of the GHSR1a receptor. By acting as a competitive antagonist to ghrelin, LEAP-2 influences energy balance and metabolic processes via the ghrelin-GHSR1a signaling pathway. LEAP-2 alone or the LEAP-2/ghrelin molar ratio showed potential as therapeutic targets for obesity, diabetes, and metabolic disorders. This review explores the recent advances of LEAP-2 in immune modulation and energy regulation, highlighting its potential in treating the above diseases.

Association between endocrine and neuropsychological endophenotypes and gambling disorder severity

BACKGROUND

Neurobiological characteristics have been identified regarding the severity of gambling disorder (GD). The aims of this study were: (1) to examine, through a path analysis, whether there was a relationship between neuroendocrine features, potentially mediational GD variables, and GD severity, and (2) to associate neuroendocrine variables, with GD severity-related variables according to gambling preferences.

METHODS

The sample included 297 outpatients with GD. We analyzed endocrine concentrations of different appetite-related hormones (ghrelin, liver antimicrobial peptide 2 [LEAP-2], leptin, adiponectin), and neuropsychological performance (working memory, cognitive flexibility, inhibition, decision making, premorbid intelligence). Path analysis assessed mechanisms between neuroendocrine features and GD severity, including mediational GD variables (impulsivity traits and gambling-related cognitive distortions). Partial correlations evaluated the associations between neuroendocrine variables, including impulsivity traits, and variables related to GD severity (DSM-5, South Oaks Gambling Screen, illness duration, and gambling-related cognitive distortions).

RESULTS

Lower adiponectin concentrations predicted greater GD severity, while higher LEAP-2 concentrations predicted more gambling-related cognitive distortions. Likewise, better neuropsychological performance directly predicted GD severity, but worse neuropsychological performance was associated with GD severity through the mediational variables of impulsivity traits and gambling-related cognitive distortions. Also, in non-strategic individuals with GD, poor working memory was associated with gambling expectancies and predictive control. In strategic individuals with GD, poor cognitive flexibility was associated with illusion of control, predictive control, and inability to stop gambling.

CONCLUSIONS

These results provide updated information about the comprehension of the interaction between neuroendocrine features, clinical variables, and severity of GD. Thus, neurobiological functions seem to be strongly related to GD severity.