Social interaction and preference are essential parts of human and animal behavior. Zebrafish are rapidly emerging as a major model organism in neurobehavioral research and, as highly social animals, enable probing of their social preference and its pharmacological modulation. Neuroactive drug effects, however, can also be socially transmittable, thereby indirectly affecting drug-free animal behavior as well. Here, we examine this possibility in adult zebrafish by assessing their social preference for conspecifics treated using a wide range of neuroactive drugs with well established effects in zebrafish. Zebrafish were treated with acute or chronic neuroactive drugs (GBR-12909, fluoxetine, reserpine, caffeine, arecoline, nicotine, cuprizone, ethanol, and atropine), and exposed to target fish in the three-chamber social preference test, scoring time the latter spent in each zone. Overall, we found their overt social preference for conspecifics treated with acute nicotine and GBR-12909, and social avoidance of fish exposed to all other drugs used, except cuprizone and ethanol. These findings confirm altered social preference for central nervous system (CNS) drug-treated zebrafish, but suggest that this preference is nonlinear and does not correlate with anxiolytic or anxiogenic drug profiles. Further research is needed to explore why some CNS drug-evoked behavioral effects render conspecifics socially attractive or aversive to observer zebrafish, and to determine potential practical and translational implications of these findings for neuropharmacology and biological psychiatry.
Parkinson’s disease is a common, highly prevalent and severely debilitating progressive neurodegenerative disorder. However, despite extensive clinical and preclinical research, the pathobiological complexity, underlying mechanisms and treatment strategies of this disorder remain poorly understood. Animal models are a valuable tool to study human brain disorders, including Parkinson’s disease. Here, we discuss the pathobiology of Parkinson’s disease, with a particular focus on zebrafish ( Danio rerio ) based genetic, pharmacological, and behavioral models that provide important insights into genetic and environmental causes of this disorder. Critically evaluating the advantages and limitations of modern zebrafish models relevant to Parkinson’s disease, we emphasize the importance of addressing both motor and nonmotor symptoms of this disorder, and also outline how these fish can facilitate further anti-Parkinson’s disease drug discovery.
Studies showed that dopamine and opioid systems in the brain have essential role in the modulation of pain perception. The evidence indicated that in the nucleus accumbens (NAc), both dopamine type 2 (D2) receptors and opioid receptors are highly expressed. However, the interaction of these systems in NAc was not investigated in the modulation of inflammatory pain. One hundred twenty-six adult male Wistar rats received unilateral microinjections of different doses of morphine (2.5, 5, 10, and 25 mmol/0.5 μl) and quinpirole (8, 16, and 32 mmol/0.5 μl) to assess their effects as opioid and D2-like receptor agonists in the NAc. In the next step, the rats were administered varying doses of sulpiride (3, 6, 12, and 24 mmol/0.5 μl), a D2-like receptor antagonist, before an effective dose of quinpirole (32 mmol/0.5 μl). They also received naloxone (1.5, 5, and 15 mmol/0.5 μl) before the same effective dose of quinpirole (32 mmol/0.5 μl). The formalin test was employed to evaluate their inflammatory pain thresholds. Results indicated that intra-accumbal administration of morphine- and quinpirole-induced antinociceptive responses. However, sulpiride significantly diminished these responses. Naloxone also reduced the quinpirole’s antinociceptive effects. Interestingly, sulpiride was less effective in reversing the analgesic effects of morphine ( η 2 = 0.17 in the first phase and η 2 = 0.37 in the late phase) than naloxone in reversing the quinpirole’s analgesic effects ( η 2 = 0.4 in the first phase and η 2 = 0.53 in the late phase). These findings suggest an interaction between the opioidergic and dopaminergic systems in pain relief.
Psilocybin has emerged as a promising therapeutic agent, with clinical benefits attributed to enhanced neuroplasticity rather than acute pharmacological effects. However, the fundamental mechanisms underlying these effects remain poorly understood. Using planarians as a model system, we investigated whether psilocybin enhances associative learning using a conditioned place preference paradigm. Following a single exposure to 5 µM psilocybin, planarians underwent 5 days of conditioning in which light was paired with sucrose. Psilocybin-treated planarians showed a significantly greater shift in light preference compared to controls (time × group × drug interaction: F (2,38) = 3.3, P < 0.05), with effects persisting at least 6 days post-administration. These findings demonstrate that psilocybin enhances appetitive associative learning in an invertebrate model, supporting the hypothesis that psychedelic-induced neuroplasticity operates through evolutionarily conserved serotonergic mechanisms.
Abstract Objective Yam virus X (YVX; Potexvirus ecsdioscoreae ) is a positive-sense, flexuous RNA virus belonging to the family Alphaflexiviridae . It has been first reported from Guadeloupe, a French archipelago located in the Caribbean Sea. In this study, we investigated the virome in yam ( Dioscorea spp.) plant material collected in the state of Bahia (Brazil) by high-throughput sequencing (HTS) on Illumina platform. The objective of the investigation was to explore the occurrence of YVX in yam from South America, and to study its genetic diversity compared to the only one YVX genome sequence available in the GenBank public database. Results An initial investigation by HTS of bulked RNA extracts (n=23, combined into 4 pools) revealed occurrence of YVX only in samples collected in the region of Valença. Subsequent screening by RT-PCR of the individual samples composing the pool uncovered infection with YVX only in Discorea trifida. Total RNA extracts from three infected plants were individually sequenced, resulting in the assembly of three complete genome sequences of YVX, showing ~84% nucleotide identity to the reference sequence from Guadeloupe. Our results contribute to expanding the pool of sequences available for YVX, supporting detection purposes and stimulating additional investigations for future studies on YVX diversity and evolution.
