Coupling of pulsed electromagnetic fields (PEMF) therapy to molecular grounds of the cell

Abstract

In this review we compile results cited in reliable journals that show a ratio for the use of pulsed electromagnetic fields (PEMF) in therapy, indeed. This is true especially for chronically inflamed joints. Furthermore, we try to link this therapeutic approach to the molecular background of chronic inflammation and arthritis. At first we start with the clinical outcome of PEMF therapy. Then, we look for possible triggers and an electromagnetic counterpart that is endogenously inherent in cell biology and in the tissues of interest. Finally, we want to investigate causal molecular and cellular mechanisms of possible PEMF actions. It shows that there are endogenous mechanisms, indeed, which can act as triggers for PEMF like the resting membrane potential as well as resonance mechanisms in charged moieties like membrane transporters. Especially voltage-gated calcium channels can be triggered. These may lead into specific signaling pathways and also may elicit nitric oxide as well as moderate radical reactions, which can ultimately lead to e.g. NFκB-like reactions. Concerted in the right way, these reactions can cause a kind of cell protection and ultimately lead to a dampening of inflammatory signals like interleukins.

Keywords: PEMF; arthritis; cell biology; endogenous electric; molecular mechanisms.

Figure 1

Different ways of PEMF-coupling to molecular biology of the cell: Upper left: ligands with polar moieties can go into resonance with PEMF-frequencies. Downstream events are elicited e.g. via receptor tyrosine kinases (RTK) PIP2 (Phosphatidylinositol 4,5-biphosphate), PIP3 (Phosphatidylinositol 3,4,5-triphosphate) and lipid Phosphatase PTEN (Phosphatase and Tensin homolog). PIP3 can signal further via Akt and Akt itself is the center of many other signaling pathways. Thus, many functional ways can be accessed by these signaling cascades. Upper right: voltage-gated calcium channels (VGCCs) can be addressed directly by PEMF. The Ca⁺⁺ stream into the cell can act on many other pathways and organelles. Bottom right: PEMF can also act by its magnetic component on radical production and in medium with oxygen also to radical oxygen species (ROS). Further, by spin triplet reorientation also a directional component can be induced. Nitric oxygen (NO) can also be released from mitochondria by PEMF and by radical production. NO and ROS in turn can also react to peroxynitride (ONOO-). This in turn will activate IκB and NFκB and this can elicit in “moderate” amounts cell reactions which lead to a kind of “pre-conditioning” and protection.