The influence of aripiprazole and venlafaxine on the antidepressant-like effect observed in prenatally stressed rats (animal model of depression)

Synthesis, computational simulations and biological evaluation of new dual 5HT1A/5HT7 receptor ligands based on purine-2,6-dione scaffold

The new dual 5HT1A/5HT7 receptor ligands were designed based on the purine-2,6-dione scaffold with the fluorine atom. Twenty-one new derivatives were synthesized, and their structure-activity relationship was summarized. Compound 11 (7-(2-(3-fluorophenyl)-2-oxoethyl)-8-((4-(4-(2-methoxyphenyl)piperazin-1-yl)butyl)amino)-1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione) showed the highest affinity to 5HT1AR and 5HT7R, and was the most potent antagonist of 5-HT1AR (Kb = 0.26 ± 0.1 nM) which activity can be to reference compound NAN-190 (Kb = 0.26 ± 0.1 nM). The experimentally established physicochemical parameters of compound 11 showed that compound, as slightly ionized in the blood, could penetrate the blood-brain barrier. A molecular docking study showed that the fluorine substitution introduces additional stabilization effects on binding to 5HT1A/5HT7Rs. In animal assays of depression and anxiety, compound 11 revealed activity in terms of dosage compared to marketed psychotropics such as fluoxetine, citalopram, and sertraline.

Quetiapine Ameliorates MIA-Induced Impairment of Sensorimotor Gating: Focus on Neuron-Microglia Communication and the Inflammatory Response in the Frontal Cortex of Adult Offspring of Wistar Rats

The maternal immune activation produced by the systemic administration of lipopolysaccharide (LPS) in rats provides valuable insights into the basis of behavioural schizophrenia-like disturbances and biochemical changes in the brains of the offspring, such as microglial activation. Regarding therapy, antipsychotics continually constitute the cornerstone of schizophrenia treatment. To their various efficacy and side effects, as well as not fully recognised mechanisms of action, further characteristics have been suggested, including an anti-inflammatory action via the impact on neuron–microglia axes responsible for inhibition of microglial activation. Therefore, in the present study, we sought to determine whether chronic treatment with chlorpromazine, quetiapine or aripiprazole could influence schizophrenia-like behavioural disturbances at the level of sensorimotor gating in male offspring prenatally exposed to LPS. Simultaneously, we wanted to explore if the chosen antipsychotics display a positive impact on the neuroimmunological parameters in the brains of these adult animals with a special focus on the ligand-receptor axes controlling neuron–microglia communication as well as pro- and anti-inflammatory factors related to the microglial activity. The results of our research revealed the beneficial effect of quetiapine on deficits in sensorimotor gating observed in prenatally LPS-exposed offspring. In terms of axes controlling neuron–microglia communication and markers of microglial reactivity, we observed a subtle impact of quetiapine on hippocampal Cx3cl1 and Cx3cr1 levels, as well as cortical Cd68 expression. Hence, further research is required to fully define and explain the involvement of quetiapine and other antipsychotics in Cx3cl1-Cx3cr1 and/or Cd200-Cd200r axes modulation and inflammatory processes in the LPS-based model of schizophrenia-like disturbances.

Developmental Neurotoxicity of Environmentally Relevant Pharmaceuticals and Mixtures Thereof in a Zebrafish Embryo Behavioural Test

Humans are exposed daily to complex mixtures of chemical substances via food intake, inhalation, and dermal contact. Developmental neurotoxicity is an understudied area and entails one of the most complex areas in toxicology. Animal studies for developmental neurotoxicity (DNT) are hardly performed in the context of regular hazard studies, as they are costly and time consuming and provide only limited information as to human relevance. There is a need for a combination of in vitro and in silico tests for the assessment of chemically induced DNT in humans. The zebrafish (Danio rerio) embryo (ZFE) provides a powerful model to study DNT because it shows fast neurodevelopment with a large resemblance to the higher vertebrate, including the human system. One of the suitable readouts for DNT testing in the zebrafish is neurobehaviour (stimulus-provoked locomotion) since this provides integrated information on the functionality and status of the entire nervous system of the embryo. In the current study, environmentally relevant pharmaceuticals and their mixtures were investigated using the zebrafish light-dark transition test. Zebrafish embryos were exposed to three neuroactive compounds of concern, carbamazepine (CBZ), fluoxetine (FLX), and venlafaxine (VNX), as well as their main metabolites, carbamazepine 10,11-epoxide (CBZ 10,11E), norfluoxetine (norFLX), and desvenlafaxine (desVNX). All the studied compounds, except CBZ 10,11E, dose-dependently inhibited zebrafish locomotor activity, providing a distinct behavioural phenotype. Mixture experiments with these pharmaceuticals identified that dose addition was confirmed for all the studied binary mixtures (CBZ-FLX, CBZ-VNX, and VNX-FLX), thereby supporting the zebrafish embryo as a model for studying the cumulative effect of chemical mixtures in DNT. This study shows that pharmaceuticals and a mixture thereof affect locomotor activity in zebrafish. The test is directly applicable in environmental risk assessment; however, further studies are required to assess the relevance of these findings for developmental neurotoxicity in humans.