The study presents a newly constructed modification of a random positioning machine (RPM) used in 3D-clinostat and in random mode. The main purpose is to provide an RPM animal model that uses up to four experimental animals simultaneously. In order to validate our RPM, the gravity dispersion and its magnitude are compared with the ones of a traditional machine. The results showed no crucial deviations in gravity dispersion and its time-averaged value in all sets of parameters. Furthermore, a posteriori stress tests are conducted on three Wistar male rats groups in order to estimate the level of stress from the setup. The social trait results suggest that the group exposed to our device has no increase in anxiety.

Phytoecdysteroids (PEs) are naturally occurring steroid compounds, that have recently gained significant attention, due to their diverse biological activities and high therapeutic potential. The aim of the present study was to quantify some PEs including 20-hydroxyecdysterone (20-HE), ponasterone A (PA), and turkesterone (TU) in selected plant foods and Rhaponticum carthamoides extract. Furthermore, the effects of 20-HE, TU, and R. carthamoides extract, were investigated with in vitro methods using isolated smooth muscle tissues. The levels of 20-HE in the analyzed samples exhibited significant differences, with kaniwa seed extract containing the highest amount, followed by spinach leaf extract, quinoa seed extract, and asparagus stem extract. The in vitro analyses suggested that R. carthamoides extract exhibits dose-dependent cytotoxic effects on smooth muscle cells, with low doses promoting contraction and higher doses inducing relaxation. Additionally, the extract demonstrated a significant inhibitory effect on ACh-induced contractions, while 20-HE enhanced the contractile response. The current findings highlighted phytoecdysteroids’ potential for modifying gastrointestinal motility.

The influence of accelerated electrons on neuronal structures is scarcely explored compared to gamma and X-rays. This study aims to investigate the effects of accelerated electron radiation on some pivotal neurotransmitter circuits (cholinergic and serotonergic) of rats’ myenteric plexus. Male Wistar rats were irradiated with an electron beam (9 MeV, 5 Gy) generated by a multimodality linear accelerator. The contractile activity of isolated smooth muscle samples from the gastric corpus was measured. Furthermore, an electrical stimulation (200 μs, 20 Hz, 50 s, 60 V) was performed on the samples and an assessment of the cholinergic and serotonergic circuits was made. Five days after irradiation, the recorded mechanical responses were biphasic—contraction/relaxation in controls and contraction/contraction in irradiated samples. The nature of the contractile phase of control samples was cholinergic with serotonin involvement. The relaxation phase involved ACh-induced nitric oxide release from gastric neurons. There was a significant increase in serotonergic involvement during the first and second contractile phases of the irradiated samples, along with a diminished role of acetylcholine in the first phase. This study demonstrates an increased involvement of serotonergic neurotransmitter circuits in the gastric myenteric plexus caused by radiation with accelerated electrons.

The genus Marrubium (Lamiaceae) is widely used in traditional medicine. While some representatives of the genus have been well investigated, the biological activity of others remains largely unknown. The aim of the current study was to assess the in vitro antioxidant potential and the effect on the reactivity of isolated rat gastric smooth muscles (SM) of aqueous extracts of Marrubium friwaldskyanum inflorescences, stems and leaves, and Marrubium peregrinum as a whole herb. The antioxidant activity was analyzed through multiple spectrophotometric and fluorometric assays. The effect on SM reactivity was determined by the treatment of excised gastric muscles of 10 male Whistar rats with the plant extracts alone or successive to 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide, ketanserin, verapamil, and acetylcholine. According to the obtained results, the M. friwaldskyanum leaf extract exhibited the greatest antioxidant potential, followed by the M. peregrinum one. The SM reactivity analysis revealed that the treatment with all four extracts induced a dose-dependent contractile response with predominant cholinergic character. However, activation of serotoninergic and/or dopaminergic pathways was also observed. Furthermore, when applied after verapamil, the extracts showed a SM relaxant effect. The discovered biological activity will serve as a basis for future analyses through which the therapeutic effect of the plants will be investigated.

Weightlessness significantly impacts physiological systems. In the current study, we investigate the effects of 7 days exposure of rats to simulated microgravity (using a modified rat-modeled random positioning machine, working with four experimental animals simultaneously) on local carrageenan-induced inflammation and serum levels of liver enzymes, metabolites (glucose, urea, creatinine), and metabolic hormones (thyroid-stimulating hormone – TSH, aldosterone, cortisol). Male Wistar rats (n=12, m=200 ± 20 g) were evenly divided into RPM (experimental) and RPM-K (control) groups. The RPM rats showed a notable mass decrease compared to the controls. A significant increase in the carrageenan-induced inflammatory response was reached on the 24^th hour in the RPM group compared to the RPM-K. Simulated microgravity resulted in lower serum glucose, creatinine, cortisol, and elevated urea levels. In conclusion, 7 days of exposure to random positioning machine-simulated microgravity promotes a pro-inflammatory state, potentially affecting insulin sensitivity, glucose utilization, and muscle catabolism.

Salvia officinalis L. (S. officinalis) or common sage has long been valued in traditional medicine for its broad therapeutic properties. Our study explored the antioxidant potential, the cytotoxic activity and the effects on smooth muscle (SM) contractility of a traditionally prepared sage aqueous infusion. A chromatographic analysis revealed the major phenolic constituents of the infusion, rosmarinic acid being the most abundant compound (38.16 mg/mL), followed by rutin (3.58 mg/g), caffeic acid (3.00 mg/g) and hesperidin (1.84 mg/g). Three spectrophotometric methods were used to determine the antioxidant potential of the plant extract: a DPPH assay for radical scavenging activity (IC₅₀ 21.77 ± 0.98 µg/mL), a CUPRAC assay (2.32 ± 0.04 mmol Trolox equivalents/g) and a total reducing capacity assay (1.92 ± 0.01 mmol Trolox equivalents/g) for evaluating reducing properties. A cytotoxicity was assessed in primary SM cells (isolated from rat gastric tissue) using the xCELLigence real-time cell analysis system, where the infusion demonstrated dose-dependent cytotoxicity with an IC₅₀ of 0.34 ± 0.12 mg/mL. Concentrations of 0.37 mg/mL rapidly reduced viability, while lower concentrations showed mild or negligible effects. Functional experiments with isolated rat gastric SM cells revealed a dose-dependent enhancement of both tonic and phasic contractile activity. Our results showed that the serotonergic pathways were mainly implicated in mediating these effects, while the cholinergic pathways were not involved with them. Together, these findings validate the traditional use of S. officinalis and point to its role in modulating SM function and providing antioxidant benefits, warranting further investigation into its mechanisms and therapeutic potential.