Anti-Radical Activity of Low Frequency and Low Amplitude PEMF

Many hypotheses have been done to understand how Pulsed Electromagnetic Fields (PEMF) at low frequency (LF) and low intensities/amplitude (LA) impact on biological tissues. One of the responses it is aimed to investigate is the LF LA PEMF capability of promoting an oxidative stress modulation and anti-radical activity. Nonlinear models and, upon all, Schrödinger equations explains what could be the energy activation which drives these changes: the soliton wave. This solution finds its biophysical and biological demonstration in oxidative stress changes, disease or sport related. In vitro test was performed to demonstrate this model. Fibroblast and endothelial cells were exposed to PEMF LFLA 0-300Hz, 100uT emitted from a solenoid for 30 minutes for 21 Days. The assay kit revealed a progressive reduction of oxidative stress after the 8th day, in both cultures. This test was followed by an explorative clinical test report involving n.5 professional running athletes who were exposed for 21 days, once a day, to PEMF LFLA (variable frequencies 0-300Hz and 100uT mean peak) through a multi-solenoid mattress. The photometric analysis done every week (0, 7 th , 14 th , 21 st day) showed a mean reduction of oxidative stress before and after each treatment, and in the overall treatment. The theorical and experimental evidence described in this report illustrate the working principle of PEMF LF LA inducing responses in oxidative stress levels of biological tissues, both in vitro and in vivo . Further studies in wider population need to be done in order to confirm these assumptions. present study it is presented a biophysical hypothesis of interaction between PEMF and biological working principle regarding the oxidative stress modulation PEMF derived, particularly in sport activities. Finally, we evidenced some results in vitro in fibroblast and endothelial cells and in vivo , in a case report on professional running athletes.


Introduction
If we expose biological tissue to Pulsed Electromagnetic Fields (PEMF) we can induce a measurable biological response and modulate inflammatory processes, promote bone repair, repair of skin wounds, even chronic ones, improve metabolic processes.
Electromagnetic fields can interact with biological tissue inducing responses depending on their frequency and intensity. In the therapeutic field, the most promising results are obtained with the use of low intensity and very low frequency pulsed electromagnetic fields, or Extremely Low Frequency, indicated by the acronym PEMF LFLA. In fact, exposing cultures of fibroblasts and endothelial cells to PEMF LFLA, which vary during the stimulation process, we can quantitatively measure a reduction in the free radicals produced.
Recent evidence has demonstrated that LPEMFs can prevent inflammation and oxidative stress as a non-invasive therapeutic method for various diseases. As an example, in 2019 a study [1] presented how, in an in vivo test, PEMF LFLA promote functional recovery following spinal cord injury, potentially by modulating inflammation, oxidative stress and HSP70. Furthermore, studies confirmed that PEMF LFLA can reduce ROS levels and enhance antioxidative stress responses in osteoblasts [2]. A polish clinical research [3] in 2018, attested that variable low frequency PEMF therapy meaningfully improved the overall condition of 57 patients through a decrease of oxidative stress markers while significantly affected positively their psychophysical abilities after stroke. In the present study it is presented a biophysical hypothesis of interaction between PEMF and biological working principle regarding the oxidative stress modulation PEMF derived, particularly in sport activities. Finally, we evidenced some results in vitro in fibroblast and endothelial cells and in vivo, in a case report on professional running athletes.

Biophysical Hypotheses Of Interaction between PEMF and Biological Tissues
There are several hypotheses of interaction between electromagnetic fields and cellular structures. Among the various hypotheses proposed in the scientific literature, the use of nonlinear physical descriptive models, seem to be the best tools for describing the induced biological phenomena. In particular, the use of solutions of Schrödinger equation, relating to waves with constant amplitude, called "solitons", which will be better described below, allows to explain, as a theoretical model, the effects of PEMFs

Effectiveness of oxidation-reduction reactions
Electro-magnetic fields can influence biological redox processes. The electron transport chain, involved in the synthesis of ATP and in respiration, is a process of oxygen reduction (by NADH and FADH2) through electron transfer in the mitochondria (it is the initial part of oxidative phosphorylation). The relatively small mass molecules involved in the chain, such as cytochrome-c, can move quite "easily" out of the mitochondrial membrane, carrying electrons from donor to acceptor [4]. This electron transport can be described using very complex physical theoretical modelling.
Trying to simplify, the various models consider electron donor molecules loosely bound to "bridging" molecules, in turn loosely bound to acceptor molecules. But if we consider high molecular weight molecules such as the NADH-ubiquinone oxidoreductase proteins and cytochrome c-oxidase, which are also involved in the electron transport chain, these result to be practically fixed in the inner mitochondrial membrane. Most of these proteins have an alpha-helix conformation. When the electrons are released from the donor molecule, they are transferred into the protein and accompanied by a deformation of the endoplasmic reticulum which forms a potential barrier that attracts the electron itself. A relationship between protein conformation and formation of the electron-lattice deformation bond is hypothesized.
The charges then propagate, accompanied by a deformation of the lattice. Mathematically, through the solutions of non-linear equations, it is possible to describe this propagation which assumes a waveform with particular characteristics, such as the amplitude that remains constant. We will see that this wave has been called "soliton". To demonstrate this result, the ion-resonance frequency relationship can be inserted into the solution of the non-linear Schrödinger equation, defined in quantum mechanics [5]. If we consider the presence of potential U(x,t) the formula of the equation can be written as follows: Cyclotron ion resonance is a phenomenon related to moving ions immersed in a magnetic field and is based on the Lorentz force.
The magnetic field acts on electronically charged elements such as ions (eg Na +, K +, Ca ++) and electrons, certainly available in biological systems. The magnetic field can act on the movement of these electric charges through a force called Lorentz and defined by

Biological Working Principle of ROS Regulation with PEMF Exposure
Both in the therapeutic and sports fields, an important effect of PEMF LFLA is the reduction or, more correctly, the regulation of oxidative stress. This plays an important role in numerous pathological conditions on an inflammatory basis, involving the cardiovascular, neurological, metabolic and respiratory compartments. In the respiratory tree, free radicals cause epithelial and vascular necrosis, connective tissue degradation and activation of pro-inflammatory factors [9]. Sports-related oxidative stress slows post-workout recovery, increases fatigue and the risk of myocyte injury. ROS free radicals are produced during physiological chemical reactions that use oxygen. These molecules are particularly reactive and unstable due to at least one unpaired electron in their outer orbital. To reach an electromagnetic equilibrium state, they try to "recover" that electron binding other atoms and leading to new and further unstable molecules. Modulated PEMF LF LA can reduce the average "duration" of the oxidative free radical, limiting its damage action, in particular during inflammatory processes, both acute and chronic, which limit the physiological healing processes or sports recovery. The "spin chemistry", through the "radical pair mechanism", can describe the mode of action of the low intensity magnetic field with chemical reactions [10].
During an oxidative reaction, radical pairs are formed, therefore, as known, with "unpaired" electrons. These electrons can be "parallel" or "antiparallel". In the first case the radical couple will be in the electronic "triplet" state, while in the second case the couple will be in the "singlet" state [11]. During the chemical reaction, with the formation of the radical pair, there is an interconversion between singlet and triplet states. This reaction influences the speed and the course of the chemical process and can be influenced by applied magnetic fields, in particular if they have low energy and variable frequency. The PEMF LFLA fields therefore promote the transition to a more stable state, that is the "triplet" state, reducing the "average life", that is the duration, of the free radical [12].

In vitro tests
In order to demonstrate the ROS-reducing action, PEMF LF LA was applied to in vitro cultures of fibroblasts and endothelial cells [5]. By means of a solenoid with 54 coils and a generator of sinusoidal electrical signals that allowed the combination through DDS of several sinusoids at different frequencies and above all, to make the frequencies vary during the treatment, impulsive e.m. fields have been generated. at frequencies that can be varied in the range 0-300Hz and with average intensities of 100 µT. In conditions of oxidative stress, free radicals accumulate, but by exposing cell cultures to modulated pulsed electromagnetic fields, it is possible to limit their production, or, more correctly, reduce the duration of activity of ROS by reducing their quantity overall. The following figure (Figure 2) shows the comparison of the quantities of ROS, measured by the Oxyselect kit in cultures of fibroblasts and endothelial cells [5], exposed to the described LF LAPEMF 20 minutes/day for 21 days [13]. The curves show the progressive variations of ROS species on a daily basis: in fibroblasts a reduction is observed, compared to the control, starting from the 8th day, while in endothelial cells the reduction of ROS is evident from the first exposure to PEMF LFLA 0-300Hz, 100uT.

Clinical Test Report on Athletes
An explorative clinical test report was performed in order to