AUCTORES
Globalize your Research
Research Article | DOI: https://doi.org/10.31579/2690-4861/578
1 Moscow State University M.V. Lomonosov, faculty of Biology, 119991 Moscow, Russia.
2 Federal state budgetary scientific institution "Federal research center for innovator and emerging biomedical and pharmaceutical technologies" 125315 Moscow, Russia.
*Corresponding Author: Gruzdev G. A, Moscow State University M.V. Lomonosov, faculty of Biology, 119991 Moscow, Russia.
Citation: Gruzdev G. A, Karpukhina O. V, Inozemtsev A. N, Povarnina P. Yu, (2025), Primary Screening of Selective Agonists and Adrenoreceptor Blockers on A New Paramecium Caudatum Model, International Journal of Clinical Case Reports and Reviews, 23(2); DOI:10.31579/2690-4861/578
Copyright: © 2025, Gruzdev G. A. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Received: 01 January 2025 | Accepted: 23 January 2025 | Published: 07 February 2025
Keywords: paramecium caudatum; comparative physiology; cellular model; neurotransmitters; adrenergic receptors
The study investigated the impact of selective agonists and antagonists of adrenergic receptors at different concentrations on the behavior of the unicellular organism Paramecium caudatum. It was demonstrated that exposure to methoxamine at a concentration of 10-3 M increases the movement speed of Paramecium caudatum cells but reduces the number of motile cells by activating various intracellular processes. The presence of phenylephrine at a concentration of 10-3 M in the environment decreases motor activity and exhibits similar effects to adrenaline.
The introduction of terbutaline at a concentration of 10-3 M leads to a sharp and prolonged increase in cell movement speed and overall activity, while the addition of dobutamine at a concentration of 10-3 M reduces motor activity. The study also showed the effects of selective blockers prazosin and atenolol at a concentration of 10-5 M, which manifested in the complete correction of the effects induced by the corresponding selective agonists on all investigated parameters of motor activity.
As of today, amidst the tightening of bioethical control over preclinical studies, the use of various cell cultures for screening pharmacological compounds has become more popular in the scientific community compared to research involving higher vertebrates and endeavors focused on predicting effects through computer modeling. However, pharmacological studies on cell cultures, particularly on unicellular organisms, are characterized by the diversity of employed methods and are complex in the interpretation of obtained results, leading to significant debates and discussions within this field [1].
Previously, in pioneering studies aimed at developing new methods for utilizing Paramecium caudatum as a model organism for primary screening of pharmacological compounds, we demonstrated and described a method that allowed the registration of changes in swimming behavior in response to the administered drug. This method is based on the variability of the motor activity of eukaryotic cells of Paramecium caudatum [2]. This method further confirmed its effectiveness in subsequent studies involving agonists and blockers of GABA-A receptors [3].
In our recent study, we decided to present the results obtained after optimizing our method, enabling the parallel comparison of investigated drugs, specifically selective agonists of adrenergic receptors and their blockers widely used in medical cardiological practice. This significantly accelerated data processing time and improved the quality of the results obtained, as simultaneous registration of movements placed all experimental groups in equal conditions.
The study was conducted using a sterile culture of live Paramecium caudatum cells. The organisms were maintained in conditions approximating their natural habitat, with a temperature of 21 degrees Celsius, pH ranging from 6.8 to 7.2, under a 12-hour light cycle, and a cell density of 600 cells/mL. Feeding with infusoria was performed daily with 200 μL of a Saccharomyces cerevisiae yeast solution per colony in 100 mL. To maintain the sterility of the environment, monthly filtration of the colony through a fine-dispersed sponge was carried out. Infusoria feeding was halted on the day of the experiment.
Our study comprises two series of experiments. In the first series, the effect of adrenergic receptor agonists on the motor activity of Paramecium caudatum was investigated. Selective α-1 adrenergic receptor agonists included phenylephrine (Sigma) and methoxamine (Sigma) at concentrations of 10-3 and 10-5 M. clonidine (Sigma) at concentrations of 10-3 and 10-5 M was used to activate α-2 adrenergic receptors. dobutamine (Sigma) and terbutaline (Sigma) at concentrations of 10-3 and 10-5 M, respectively, were chosen as selective β-1 and β-2 adrenergic receptor agonists.
The second series explored the possibility of correcting the effects of selective agonists with selective blockers such as prazosin (Sigma) at a concentration of 10-5 M for α-1 adrenergic receptors and atenolol (Sigma) at a concentration of 10-5 M for β-1 adrenergic receptors. Each experiment was replicated eight times and accompanied by its own control. The intact group received the Lozina-Lozinsky solution in the same volume.
The movement of cells was recorded using a trinocular stereoscopic microscope, Olympus SZ6, equipped with a 24-well plate. The volume of the investigated cell culture was one milliliter. For the analysis of motor activity based on the obtained video recordings, the ImageJ (Fiji) program with the "Track Mate" plugin was employed [4].
Statistical data processing: The statistical analysis was performed using the "Statistica 10" program with a non-parametric Two-Way ANOVA test. Significance levels were assessed at p < 0>
Prior to working with selective adrenergic receptor agonists, it was observed that the introduction of adrenaline at concentrations of 10-3 M into the medium with Paramecium caudatum cells reduces the motor activity of Paramecium caudatum (Fig. 1a, b).
Figure 1: Changes in the speed of movement and activity of Paramecium caudatum in response to the administration of adrenaline and methoxamine. a – Changes in the average speed of cell movement under the influence of adrenaline at concentrations of 10-3, 10-5, 10-7 M during a 25-minute registration period. The arrow indicates the moment of adding the drugs to the well (fifth minute of registration). Cell concentration - 600±50 cells/mL. * - significant difference from the speed of cells in the intact group, p <0>
The concept of motor activity encompasses three parameters: swimming speed, the number of actively moving cells, and the smoothness of Paramecium trajectories. Thus, the presence of adrenaline at a concentration of 10-3 M in the medium reduces the swimming speed of Paramecium caudatum by 0.7 mm/s, while lower concentrations of adrenaline did not lead to changes in this parameter (Figure. 1a). The alteration in swimming speed may be associated with a disruption in the sequence and rhythmicity of cilia beating in Paramecium. [5]. In response to the activation of adrenergic receptors by administered adrenaline, there is a manifestation of intermittent jerky movements in different directions. It is also noteworthy that there is a 50
The use of the primary screening method of pharmacological agents on the cellular model of Paramecium caudatum has demonstrated its effectiveness in determining the most active concentration of adrenoreceptor agonists. Analysis of changes in cell motility revealed a divergent effect upon activation of β-1 and β-2 adrenoreceptors in relation to the two investigated parameters. Activation of α-adrenoreceptors leads to a reduction in the number of mobile cells, corresponding to the cellular response to the presentation of adrenaline. Additionally, the study demonstrated that the introduction of selective blockers, prazosin and atenolol, completely blocks the action of selective adrenoreceptor agonists. This suggests the targeted action of these drugs on the investigated adrenoreceptors.
Gruzdev G. А “conducting an experiment, obtaining and processing data, writing a draft of the article”; Karpukhina O. V. “supervision and explanation of results”; Inozemtsev A. N. “writing – review and editing”; Povarnina P. Yu “project administration”.
All applicable international, national, and/or institutional principles for the care and use of animals were followed. This article does not contain any studies with human participants as subjects.
The research was conducted as part of the scientific project under the state assignment of Lomonosov Moscow State University (Theme №. 121032500080-8), with additional support from the Interdisciplinary Scientific and Educational School of Moscow University, "Brain, Cognitive Systems, Artificial Intelligence".
The authors declare no explicit or potential conflicts of interest associated with the.
Clearly Auctoresonline and particularly Psychology and Mental Health Care Journal is dedicated to improving health care services for individuals and populations. The editorial boards' ability to efficiently recognize and share the global importance of health literacy with a variety of stakeholders. Auctoresonline publishing platform can be used to facilitate of optimal client-based services and should be added to health care professionals' repertoire of evidence-based health care resources.
