E E Fesenko’s research while affiliated with Institute of Cell Biophysics, Russian Academy of Sciences and other places

Fourier transform infrared difference spectroscopy was used to study the effect of millimeter-range electromagnetic radiation on the structure of bacteriorhodopsin under lighting conditions. A detailed analysis of the Fourier IR spectra revealed pronounced structural changes in the region of amide I, amide II and rearrangement of the hydrogen bond network. The well-resolved peaks of the amide bands made it possible to recognize two different components (α-I and α-II) of the α-helical conformation of the opsin. Irreversible conformational changes of bacteriorhodopsin in purple membranes detected by Fourier IR difference spectroscopy suggested that microwaves induced structural rearrangements of proteins unrelated to temperature.

Fourier transform infrared (FTIR) difference spectroscopy was used to study the effects of microwaves radiation on the structure of bacteriorhodopsin under light condition. The detailed FTIR spectral analysis revealed the pronounced structural changes in amide I and amide II regions as well as the rearrangements of the hydrogen-bonding network. Well-resolved peaks of amide bands allow accurate determination of two different components (α-I and α-II) of an α-helical conformation of opsin. Irreversible conformational changes of bacteriorhodopsin in purple membranes, detected by FTIR difference spectroscopy, suggest that regardless of temperature, microwaves induce protein structural rearrangements.

The article reveals that a decrease in the background production of reactive oxygen species (ROS) in the peritoneal neutrophils of mice after a short-term (40 minutes) stay in hypomagnetic conditions (residual field  10 nT) at physiological temperatures, detected by the method of lucigenin-dependent chemiluminescence, is not accompanied by a violation of chemiluminescent response to respiratory burst activators: formylated peptide N-formyl-Met-Leu-Phe (fMLF) and phorbol ester of phorbol-12-meristat-13-acetate (PMA). These results were obtained by activated chemiluminescence using lucigenin or luminol and various combinations of ROS production activators (PMA and/or fMLF). In contrast, the action of combined parallel constant (induction 60 μT) and alternating (amplitude range 60-180 nT, frequency 49.5 Hz) magnetic fields (CMF) leads to a decrease in the chemiluminescent response to these activators. These data indicate different sources of ROS that respond to certain modes of CMF and hypomagnetic field in neutrophils. The conducted research and the previously obtained results enable to exclude the systems that control the respiratory burst in neutrophils from the main targets and acceptors that respond to short-term deprivation of the magnetic field.

Cytogenetic anomaly frequencies were analyzed in three sublines of ES Rl line in its five clonal sublines, obtained from two cell colonies after transformation of ES Rl cells by plasmid with gene lif. Cell transformation did not increase cytogenic anomalies, however, the initial sublines of ES Rl line, as well as its transformed clonal descendants bore a redundant quantity of the chromosome 8 material within the structure of various Robertsonian translocations even in cells with diploid chromosome quantity {In = 40). In the initial sublines ES Rl and its clonal descendants, a common Rb (8; 15) was revealed. It was supposed that selection for the increase in ES cell sensitivity to cytokines (in particular, LIF, under cultural conditions was accompanied by an increase in chromosomal copies, carrying genes of mapk and jak/stat, through which downstream effectors of cytokine signals for preservation of cell pluripotention and propagation are realized. Genes of chromatid separation and chromosome segregation control (for example, separase gene Espl in chromosome 15, may be passively involved in this process, thus promoting acceleration of karyotype evolution in ES cells.

Cytogenetic anomaly frequencies were analyzed in three sublines of ES Rl line in its five clonal sublines, obtained from two cell colonies after transformation of ES Rl cells by plasmid with gene lif. Cell transformation did not increase cytogenic anomalies, however, the initial sublines of ES Rl line, as well as its transformed clonal descendants bore a redundant quantity of the chromosome 8 material within the structure of various Robertsonian translocations even in cells with diploid chromosome quantity {2n = 40). In the initial sublines ES Rl and its clonal descendants, a common Rb (8; 15) was revealed. It was supposed that selection for the increase in ES cell sensitivity to cytokines (in particular, LIF) under cultural conditions was accompanied by an increase in chromosomal copies, carrying genes of mapk and jak/stat, through which downstream effectors of cytokine signals for preservation of cell pluripotention and propagation are realized. Genes of chromatid separation and chromosome segregation control (for example, separase gene Espl in chromosome 15) may be passively involved in this process, thus promoting acceleration of karyotype evolution in ES cells.

The aim of the study was to evaluate the possibility of increasing the radioprotective potential of peroxiredoxin 6 (Prdx6) and its mutant form S32A by their combined use with geldanamycin (GA) for 3T3 fibroblasts irradiated with X-rays at a dose of 6 Gy. The mutant enzyme S32A, which does not have phospholipase activity, exhibits a more pronounced radioprotective activity when combined with GA. The use of this combination of radioprotective drugs completely abolishes the peak of NF-κB activity in irradiated 3T3 cells. Another transcription factor, p53, which is an indicator of the level of cell apoptosis and increases upon irradiation, is also reduced by S32A in combination with GA. The low-molecular-weight protein p21, which is a marker of cell senescence and whose production increases upon irradiation, is also normalized when S32A is used in combination with GA. In addition, the use of this combination of radioprotective drugs significantly reduces the stress response of 3T3 cells to X-ray irradiation.

Abstract—Some current trends in the development of research on the effects and mechanisms of the biolog-ical action of weak and ultra-weak static magnetic fields, low-frequency alternating magnetic fields, combined magnetic fields, and radio frequency fields in combination with a static magnetic field are presented.Experimental studies in which interesting and somewhat unexpected effects of magnetic fields with strengthsignificantly lower than the magnetic field of the Earth (including those with intensities close to zero) wereobserved, are considered. The data are given taking into account the materials of the joint annual meeting ofthe Society of Bioelectromagnetism and the European Association of Bioelectromagnetism “BioEM 2021”(September 26–30, 2021, Ghent, Belgium).

It has been shown that pulsed magnetic fields (the first mode: pulse duration of 2 ms, frequency repetitions of 6.25 Hz, the pulse was bell-shaped; and the second mode: pulse duration of 1 ms, repetition frequency of 100 Hz, the pulse was bell-shaped) affected the intensity of luminol-dependent chemiluminescence of neutrophils in a wide range of pulsed magnetic fields (0.0004–10 mT). For the detection of the effects of pulsed magnetic fields by this method, it was necessary to add forbol-12-meristat-13-acetate, an activator of the production of reactive oxygen species, to the suspension of neutrophils. However, this mechanism of action of pulsed magnetic fields on the production of reactive oxygen species in neutrophils was not the only one, since lucigenin-dependent chemiluminescence also reacted to their action in a system without activators.

It has been shown that 30-min incubation of neutrophils in the presence of a near null magnetic field produced with the use of permalloy for magnetic shielding (a residual static magnetic field not greater than 20 nT) leads to a significant decrease (by 48%) in the intensity of lucigenin-dependent chemiluminescence measured directly after removal of the hypomagnetic field. At 20 min after being in hypomagnetic conditions (followed by a 20 min of incubation of neutrophils in the geomagnetic field), the degree of the differences between the control and experimental samples is completely preserved. When the time periods of incubation of experimental samples in the geomagnetic field (static magnetic field 44 μT) were extended (40 min and 60 min) after exposure to a near-null magnetic field, the differences between experimental and appropriate control groups of samples were smaller, by up to 32 and 22%.