The purpose of this study was to verify whether the nanosecond pulsed electric field, not eliciting thermal effects, permanently changes the molecular processes and gene expression of Leydig TM3 cells. The cells were exposed to a moderate electric field (80 quasi-rectangular shape pulses, 60 ns pulse width, and an electric field of 14 kV/cm). The putative disturbances were recorded over 24 h. After exposure to the nanosecond pulsed electric field, a 19% increase in cell diameter, a loss of microvilli, and a 70% reduction in cell adhesion were observed. Some cells showed the nonapoptotic externalization of phosphatidylserine through the pores in the plasma membrane. The cell proportion in the subG1 phase increased by 8% at the expense of the S and G2/M phases, and the DNA was fragmented in a small proportion of the cells. The membrane mitochondrial potential and superoxide content decreased by 37% and 23%, respectively. Microarray’s transcriptome analysis demonstrated a negative transient effect on the expression of genes involved in oxidative phosphorylation, DNA repair, cell proliferation, and the overexpression of plasma membrane proteins. We conclude that nanosecond pulsed electric field affected the physiology and gene expression of TM3 cells transiently, with a noticeable heterogeneity of cellular responses.

Methicillin-resistant Staphylococcus aureus (MRSA) produces virulence factors and causes hard-to-treat infections. This study aimed to evaluate the effect of trans-cinnamaldehyde (TC) on the selected virulence factors of MRSA: adhesion to host plasma and extracellular matrix proteins, protease, DNase and esterase production, and hemolytic activity. Our results showed that TC at ½ MBIC (Minimum Biofilm Inhibition Concentration) of 240 µg/mL or 60 µg/mL, depending on the isolate, significantly reduced MRSA adhesion. Inhibition varied between isolates, ranging from 26.1% to 41.3% (fibrinogen), 18.2% to 34.9% (elastin), 26.5% to 32.4% (laminin), and 17.1% to 30.5% (collagen). TC at ½ MIC (Minimum Inhibitory Concentration) of 30 µg/mL also significantly inhibited MRSA enzyme production, and reduced hemolytic activity (by 80.0–83.1%, depending on the isolate). TC may be an alternative to antibiotics for combating infections caused by S. aureus, as it not only reduces bacterial survival in the host but also reduces S. aureus virulence at subinhibitory concentrations. TC at higher concentrations exhibits cytotoxicity in human fibroblasts, limiting its topical use. Therefore, to exploit TC’s antibacterial potential, it is necessary to identify substances that act synergistically with it, enabling reduced effective doses.

The effect of nanosecond electromagnetic pulses on human health, and especially on forming free radicals in human cells, is the subject of continuous research and ongoing discussion. This work presents a preliminary study on the effect of a single high-energy electromagnetic pulse on morphology, viability, and free radical generation in human mesenchymal stem cells (hMSC). The cells were exposed to a single electromagnetic pulse with an electric field magnitude of ~1 MV/m and a pulse duration of ~120 ns generated from a 600 kV Marx generator. The cell viability and morphology at 2 h and 24 h after exposure were examined using confocal fluorescent microscopy and scanning electron microscopy (SEM), respectively. The number of free radicals was investigated with electron paramagnetic resonance (EPR). The microscopic observations and EPR measurements showed that the exposure to the high-energy electromagnetic pulse influenced neither the number of free radicals generated nor the morphology of hMSC in vitro compared to control samples.