The main symptoms of schizophrenia are categorized as positive, negative, and cognitive. Cognitive impairments do not generally respond to antipsychotics. Cariprazine is a novel antipsychotic conceived with the idea that high affinity for D3 receptors may elicit a favorable response in the management of cognitive deficits. We evaluated the pro-cognitive properties of 14-day long pre-treatment with cariprazine (0.25, 0.5, and 1 mg/kg b.w. intraperitoneally) in experimental rodent models with scopolamine-induced memory impairment employing novel object recognition test (NORT), T-maze, Y-maze, and passive avoidance tasks (step-through and step-down). Statistical analysis was performed with One Way ANOVA. In NORT cariprazine increased the recognition index. In T-maze and Y-maze cariprazine increased the working memory index as well as the percentage of spontaneous alternation. Cariprazine improved learning and memory in both short-term and long-term memory retention tests in step-down and step-through tasks. Cariprazine improves learning, recognition, and spatial memory in rats with scopolamine-induced memory impairment. Cariprazine’s beneficial effect on cognition is likely due to its affinity for D3 receptors, as well as agonism at 5-HT1A receptors. Most probably, the cognitive-enhancing properties of cariprazine are the result of integrated modulation in the amygdala, hippocampus, and prefrontal cortex.

Cannabidiol (CBD), a non-psychoactive compound derived from Cannabis sativa, is believed to have anxiety-reducing and antidepressant effects. However, existing data are inconsistent, likely due to variations in experimental designs, dosages, and stress models. This study sought to assess the impact of CBD on anxiety and depression-like behaviors in Wistar rats exposed to acute cold stress, as well as its impact on pro- and anti-inflammatory cytokines. Male rats were treated with CBD (2.5, 5, or 10 mg/kg) or vehicle for 14 days and subjected to behavioral tests, including the elevated plus maze, social interaction, and forced swim tests. Serum levels of cytokines (IL-6, TNF-α, IL-1β, and IL-10) were analyzed post-experiment using ELISA. Results demonstrated a dose-dependent anxiolytic effect of CBD, with significant improvements in social interaction and reductions in anxiety-like behaviors at 5 and 10 mg/kg. All doses of CBD decreased immobility in the forced swim test, suggesting antidepressant effects. Furthermore, CBD selectively lowered IL-6 levels, a key cytokine in acute stress and depression pathogenesis. These findings indicate that CBD has anxiety-reducing and antidepressant properties, partially mediated by modulation of inflammatory processes, particularly IL-6.

Aim: Memory improving and anti-inflammatory properties of cannabidiol (CBD) were investigated in an experimental model of lipopolysaccharide (LPS)-induced inflammation. Materials and methods: Male Wistar rats were randomly divided into 4 groups: control, LPS control, LPS + CBD 5 mg/kg bw, and LPS + CBD 10 mg/kg bw. Animals were treated with CBD 14 days before LPS administration and throughout the experiment. Step-through passive avoidance task, Y-maze, and novel object recognition test (NORT) were used to assess the memory functions. The following parameters were recorded: latency time, spontaneous alternations percentage (SA%) and recognition index (RI). IL-10, IL-6, TNF-α, and IL-1β serum levels were measured to evaluate the immunomodulatory properties of CBD. Results: LPS led to significant decrease of the recorded parameters in all memory tasks. This demonstrated the memory-impairing effect of LPS-induced inflammation. In the Y-maze and NORT tests, both doses of CBD increased SA% and RI, respectively. Significant difference was found in comparison with the LPS controls. Rats from the CBD treated groups showed increased latency in the step-through passive avoidance task. In the short-term memory test, both CBD doses significantly increased this parameter when compared with both control groups (p<0.05 and p<0.001, respectively), whereas in the long-term memory test, statistical significance was reached only in comparison with the LPS controls (p<0.01). CBD treatment failed to reduce TNF-α and IL-6 serum levels. The lower studied dose significantly decreased IL-10 and IL-1β concentrations compared to LPS controls (p<0.01 and p<0.05, respectively). Conclusions: CBD improved spatial working and recognition memory in rats with LPS-induced inflammation. Suppression of IL-1β production could be attributed to the observed effect.