Growth of etiolated barley plants in weak static and 50 Hz electromagnetic fields tuned to calcium ion cyclotron resonance

Background

The effects of weak magnetic and electromagnetic fields in biology have been intensively studied on animals, microorganisms and humans, but comparably less on plants. Perception mechanisms were attributed originally to ferrimagnetism, but later discoveries required additional explanations like the "radical pair mechanism" and the "Ion cyclotron resonance" (ICR), primarily considered by Liboff. The latter predicts effects by small ions involved in biological processes, that occur in definite frequency- and intensity ranges ("windows") of simultaneously impacting magnetic and electromagnetic fields related by a linear equation, which meanwhile is proven by a number of in vivo and in vitro experiments.

Methods

Barley seedlings (Hordeum vulgare, L. var. Steffi) were grown in the dark for 5 and 6 days under static magnetic and 50 Hz electromagnetic fields matching the ICR conditions of Ca²⁺. Control cultures were grown under normal geomagnetic conditions, not matching this ICR. Morphology, pigmentation and long-term development of the adult plants were subsequently investigated.

Results

The shoots of plants exposed to Ca²⁺-ICR exposed grew 15–20% shorter compared to the controls, the plant weight was 10–12% lower, and they had longer coleoptiles that were adhering stronger to the primary leaf tissue. The total pigment contents of protochlorophyllide (PChlide) and carotenoids were significantly decreased. The rate of PChlide regeneration after light irradiation was reduced for the Ca²⁺-ICR exposed plants, also the Shibata shift was slightly delayed. Even a longer subsequent natural growing phase without any additional fields could only partially eliminate these effects: the plants initially exposed to Ca²⁺-ICR were still significantly shorter and had a lower chlorophyll (a+b) content compared to the controls. A continued cultivation and observation of the adult plants under natural conditions without any artificial electromagnetic fields showed a retardation of the originally Ca²⁺-ICR exposed plants compared to control cultures lasting several weeks, with an increased tendency for dehydration.

Conclusion

A direct influence of the applied MF and EMF is discussed affecting Ca²⁺ levels via the ICR mechanism. It influences the available Ca²⁺ and thereby regulatory processes. Theoretical considerations on molecular level focus on ionic interactions with water related to models using quantum electrodynamics.

     

Calcium ion cyclotron resonance in dissipative water structures

Weak magnetic and electromagnetic fields affect physiological processes in animals, plants, and microorganisms. Ion cyclotron resonance (ICR) is discussed as one of the sensitive mechanisms, which enable perception of the geomagnetic field and its orientation. Numerous biological effects are observed involving several small ions, showing windows of predicted frequencies and intensities. The pioneering work of Guiliano Preparata and Emilio Del Giudice using quantum electrodynamics showed that spontaneously originating coherent regions in water facilitate ICR effects at incoherent water phase boundaries. Here we examine the ICR response of the calcium ion (Ca²⁺), crucial for many life processes. We use an aqueous solution containing the biologically ubiquitous membrane lipid L-α-phosphatidylcholine that serves as a biomimetic proxy for dynamic light scattering (DLS) and nonlinear dielectric spectroscopy (NLDS) measurements. One notable result is that this system approaches a new equilibrium upon addition of calcium by means of the oscillatory Belousov–Zhabotinsky chemical reaction, oscillations are significantly reduced under Ca²⁺ ICR application. Secondly an “oscillator” of calcium ions appears to be able to itself couple coherently and predictably to large-scale coherent regions in water. This system appears able to regulate ion fluxes in response to very weak environmental electromagnetic fields.     

Effects of exposure to a time-varying 1.5 T magnetic field on the neurotransmitter-activated increase in intracellular Ca in relation to actin fiber and mitochondrial functions in bovine adrenal chromaffin cells

Background

It has been reported that exposure to electromagnetic fields influences intracellular signal transduction. We studied the effects of exposure to a time-varying 1.5 T magnetic field on membrane properties, membrane cation transport and intracellular Ca²⁺ mobilization in relation to signals. We also studied the mechanism of the effect of exposure to the magnetic field on intracellular Ca²⁺ release from Ca²⁺ stores in adrenal chromaffin cells.

Methods

We measured the physiological functions of ER, actin protein, and mitochondria with respect to a neurotransmitter-induced increase in Ca²⁺ in chromaffin cells exposed to the time-varying 1.5 T magnetic field for 2 h.

Results

Exposure to the magnetic field significantly reduced the increase in [Ca²⁺]i. The exposure depolarized the mitochondria membrane and lowered oxygen uptake, but did not reduce the intracellular ATP content. Magnetic field-exposure caused a morphological change in intracellular F-actin. F-actin in exposed cells seemed to be less dense than in control cells, but the decrease was smaller than that in cytochalasin D-treated cells. The increase in G-actin (i.e., the decrease in F-actin) due to exposure was recovered by jasplakinolide, but inhibition of Ca²⁺ release by the exposure was unaffected.

Conclusions and general significance

These results suggest that the magnetic field-exposure influenced both the ER and mitochondria, but the inhibition of Ca²⁺ release from ER was not due to mitochondria inhibition. The effect of eddy currents induced in the culture medium may indirectly influence intracellular actin and suppress the transient increase in [Ca²⁺]i.     

Weak extremely-low-frequency magnetic fields and regeneration in the planarian Dugesia tigrina

Extremely-low-frequency (ELF), low-intensity magnetic fields have been shown to influence cell signaling processes in a variety of systems, both in vivo and in vitro. Similar effects have been demonstrated for nervous system development and neurite outgrowth. We report that regeneration in planaria, which incorporates many of these processes, is also affected by ELF magnetic fields. The rate of cephalic regeneration, reflected by the mean regeneration time (MRT), for planaria populations regenerating under continuous exposure to combined DC (78.4 μT) and AC (60.0 Hz at 10.0 μT _peak) magnetic fields applied in parallel was found to be significantly delayed (P ? 0.001) by 48 ± 1 h relative to two different types of control populations (MRT ? 140 ± 12 h). One control population was exposed to only the AC component of this field combination, while the other experienced only the ambient geomagnetic field. All measurements were conducted in a low-gradient, low-noise magnetics laboratory under well-maintained temperature conditions. This delay in regeneration was shown to be dependent on the planaria having a fixed orientation with respect to the magnetic field vectors. Results also indicate that this orientation-dependent transduction process does not result from Faraday induction but is consistent with a Ca²⁺ cyclotron resonance mechanism. Data interpretation also permits the tentative conclusion that the effect results from an inhibition of events at an early stage in the regeneration process before the onset of proliferation and differentiation. © 1995 Wiley-Liss, Inc.     

Ca2+ ion transport through patch-clamped cells exposed to magnetic fields

The total current of Ca²⁺ ions through patch-clamped cell membranes was measured while exposing clonal insulin-producing β-cells (RINm5F) to a combination of DC and AC magnetic fields at so-called cyclotron resonance conditions. Previous experimental evidence supports the theory that a resonant interaction between magnetic fields and organisms can exist. This experiment was designed to test one possible site of interaction: channels in the cell membrane. The transport of Ca²⁺ ions through the protein channels of the plasma membrane did not show any resonant behavior in the frequency range studied. © 1995 Wiley-Liss, Inc.     

Effect of weak combined magnetic fields on the metamorphosis of the mealworm beetle Tenebrio molitor

The effects of weak combined magnetic fields adjusted to the parametric resonance for Ca²⁺ and K⁺ and extremely weak alternating magnetic field on the metamorphosis of the mealworm beetle Tenebrio molitor have been studied. It was shown that the exposure of pupas of insects to all above-indicated types of fields stimulates the metamorphosis. However, after the exposure to weak combined magnetic fields adjusted to the parametric resonance for Ca²⁺ and K⁺, the number of insects with anomalies increases, which is not observed by the action of the weak alternating magnetic field.     

Calcium Ion Cyclotron Resonance (ICR), 7.0 Hz, 9.2 μT Magnetic Field Exposure Initiates Differentiation of Pituitary Corticotrope-Derived AtT20 D16V Cells

The aim of this work is the study of the effect of electromagnetic radiations (ELF-EMF) tuned to the calcium cyclotron resonance condition of 7.0?Hz, 9.2?μT on the differentiation process of pituitary corticotrope-derived AtT20 D16V cells. These cells respond to nerve growth factor by extending neurite-like processes. To establish whether exposure to the field could influence the molecular biology of the pituitary gland, a corticotrope-derived cells line (AtT20 D16V) was exposed to ELF-EMF at a frequency of 7.0?Hz, 9.2?μT electromagnetic field by a Vega Select 719 power supply. Significant evidence was obtained to conclude that as little as 36?h exposure to the Ca²⁺ ICR condition results in enhanced neurite outgrowth, with early expression and aggregation of the neuronal differentiation protein NF-200 into neurite structures.     

The <Emphasis Type="Italic">Drosophila</Emphasis>STIM1 orthologue,dSTIM, has roles in cell fate specification and tissue patterning

Background  

Mammalian STIM1 and STIM2 and the single Drosophila homologue dSTIM have been identified as key regulators of store-operated Ca²⁺ entry in cells. STIM proteins function both as molecular sensors of Ca²⁺concentration in the endoplasmic reticulum (ER) and the molecular triggers that activate SOC channels in the plasma membrane. Ca²⁺ is a crucial intracellular messenger utilised in many cellular processes, and regulators of Ca²⁺ homeostasis in the ER and cytosol are likely to play important roles in developmental processes. STIM protein expression is altered in several tumour types but the role of these proteins in developmental signalling pathways has not been thoroughly examined.     

Effects of extremely-law-frequency electromagnetic fields on ion transport in several mammalian cells

We have investigated the effects of sinusoidal electromagnetic fields (EMF) on ion transport (Ca²⁺, Na⁺, K⁺, and H⁺) in several cell types (red blood cells, thymocytes, Ehrlich ascites tumor cells, and HL60 and U937 human leukemia cells). The effects on the uptake of radioactive tracers as well as on the cytosolic Ca²⁺ concentration ([Ca²⁺]_i), the intracellular pH (pH_i), and the transmembrane potentsial (TMP) were studied. Exposure to EMF at 50 Hz and 100–2000 μT (rms) had no significant effects on any of these parameters. Exposure to EMF of 20–1200 μT (rms) at the estimated cyclotron magnetic resonance frequencies for the respective ions had no significant effects except for a 12–32% increase of the uptake of ⁴²K within a window at 14.5–15.5 Hz and 100–200 μT (rms), which was found in U937 and Ehrlich cells but not in the other cell types. © 1994 Wiley-Liss, Inc.     

Correlation of magnetic AC field on cardiac myocyte Ca2+ transients at different magnetic DC levels

The purpose of this study was to determine the effect of extremely low frequency and weak magnetic fields (WMF) on cardiac myocyte Ca²⁺ transients, and to explore the involvement of potassium channels under the WMF effect. In addition, we aimed to find a physical explanation for the effect of WMF on cardiac myocyte Ca²⁺ transients. Indo‐1 loaded cells, which were exposed to a WMF at 16 Hz and 40 nT, demonstrated a 75 ± 4% reduction in cytosolic Ca²⁺ transients versus control. Treatment with the K_ATP channel blocker, glibenclamide, followed by WMF at 16 Hz exposure, blocked the reduction in cytosolic calcium transients while treatment with pinacidil, a K_ATP channel opener, or chromanol 293B, a selective potassium channel blocker of the delayed rectifier K⁺ channels, did not inhibit the effect. Based on these finding and the ion cyclotron resonance frequency theory, we further investigated the effect of WMF by changing the direct current (DC) magnetic field (B₀). When operating different DC magnetic fields we showed that the WMF value changed correspondingly: for B₀ = 44.5 µT, the effect was observed at 17.05 Hz; for B₀ = 46.5 µT, the effect was observed at 18.15 Hz; and for B₀ = 49 µT the effect was observed at 19.1 Hz. We can conclude that the effect of WMF on Ca²⁺ transients depends on the DC magnetic field level. Bioelectromagnetics 33:634–640, 2012. © 2012 Wiley Periodicals, Inc.     

Modeling CICR in rat ventricular myocytes: voltage clamp studies

Background  

The past thirty-five years have seen an intense search for the molecular mechanisms underlying calcium-induced calcium-release (CICR) in cardiac myocytes, with voltage clamp (VC) studies being the leading tool employed. Several VC protocols including lowering of extracellular calcium to affect Ca ²⁺ loading of the sarcoplasmic reticulum (SR), and administration of blockers caffeine and thapsigargin have been utilized to probe the phenomena surrounding SR Ca ²⁺ release. Here, we develop a deterministic mathematical model of a rat ventricular myocyte under VC conditions, to better understand mechanisms underlying the response of an isolated cell to calcium perturbation. Motivation for the study was to pinpoint key control variables influencing CICR and examine the role of CICR in the context of a physiological control system regulating cytosolic Ca ²⁺ concentration ([Ca ²⁺] _myo ).     

cAMP controls cytosolic Ca<Superscript>2+</Superscript> levels in <Emphasis Type="Italic">Dictyostelium discoideum</Emphasis>

Background  

Differentiating Dictyostelium discoideum amoebae respond upon cAMP-stimulation with an increase in the cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) that is composed of liberation of stored Ca²⁺ and extracellular Ca²⁺-influx. In this study we investigated whether intracellular cAMP is involved in the control of [Ca²⁺]_i.     

Abnormal expression, localization and interaction of canonical transient receptor potential ion channels in human breast cancer cell lines and tissues: a potential target for breast cancer diagnosis and therapy

Background  

Ca²⁺ is known to be involved in a number of metastatic processes including motility and proliferation which can result in store-depletion of Ca²⁺. Up regulation of genes which contribute to store operated channel (SOC) activity may plausibly be necessary for these processes to take place efficiently. TRPC proteins constitute a family of conserved Ca²⁺-permeable channels that have been shown to contribute to SOC activity.     

A new short-term toxicity assay using <Emphasis Type="Italic">Aspergillus awamori</Emphasis> with recombinant aequorin gene

Background  

Most currently available short-term toxicity assays are based on bacterial cells. Therefore there is a need for novel eukaryotic microbial bioassays that will be relevant to higher eukaryotes such as animals and plants. Ca²⁺ is a universal intracellular signalling molecule found in all organisms from prokaryotes to highly specialized animal cells. In fungi calcium has been demonstrated to be involved in control of many important processes. The recombinant aequorin gene from the jellyfish Aequorea victoria responsible for the expression of the Ca²⁺-sensitive aequorin photoprotein has been cloned in the filamentous fungus Aspergillus awamori. This has allowed real life monitoring of [Ca²⁺]_c changes in living fungal cells. When subjected to different physico-chemical stimuli fungal cells respond by transiently changing the concentration of free Ca²⁺ in the cytosol ([Ca²⁺]_c) and the pattern of these changes (Ca²⁺ signature) is specific to each particular stimulus. Therefore it was interesting to investigate whether different environmental toxicants would be able to affect the pattern of [Ca²⁺]_c changes in a reproducible and dose dependant manner.     

Aberrant stalk development and breakdown of tip dominance in Dictyostelium cell lines with RNAi-silenced expression of calcineurin B

Background  

Calcineurin, the Ca²⁺/calmodulin-dependent protein phosphatase, plays important roles in various cellular processes in lower and higher eukaryotes. Here we analyze the role of calcineurin in the development of Dictyostelium discoideum by RNAi-mediated manipulation of its expression.     

Disruption of actin filaments induces mitochondrial Ca<Superscript>2+</Superscript> release to the cytoplasm and [Ca<Superscript>2+</Superscript>]<Subscript>c</Subscript> changes in <Emphasis Type="Italic">Arabidopsis</Emphasis>root hairs

Background  

Mitochondria are dynamic organelles that move along actin filaments, and serve as calcium stores in plant cells. The positioning and dynamics of mitochondria depend on membrane-cytoskeleton interactions, but it is not clear whether microfilament cytoskeleton has a direct effect on mitochondrial function and Ca²⁺ storage. Therefore, we designed a series of experiments to clarify the effects of actin filaments on mitochondrial Ca²⁺ storage, cytoplasmic Ca²⁺ concentration ([Ca²⁺]_c), and the interaction between mitochondrial Ca²⁺ and cytoplasmic Ca²⁺ in Arabidopsis root hairs.     

Modulation of Ca2+ dependent protease activity in fish and invertebrates by weak low-frequency magnetic fields

Results of experiments addressing the effects of weak low-frequency magnetic fields on intracellular Ca²⁺ dependent proteinases (calpains) from invertebrates and fish are discussed. Exposure of live animals to weak low-frequency magnetic fields with parameters chosen to induce the resonance of Ca²⁺ ions led to a significant decrease of calpain activity in the animals investigated. The physical factor studied also caused partial loss of activity in preparations of Ca²⁺ dependent proteinases obtained from invertebrates and fish. The phenomenon discovered is in accordance with the interference model of the effect of weak low-frequency magnetic fields on biological objects.     

The influence of weak magnetic fields on the production of the reactive oxygen species in peritoneal neutrophils of mice

The influence of weak magnetic fields of different types on the rate of the formation of reactive oxygen species in mouse peritoneal neutrophils has been studied. It was found that the exposure of neutrophils activated by phorbol 12-myristate 13-acetate to the magnetic field tuned to the parametric resonance for Ca²⁺ ions leads to a decrease in the rate of the reactive oxygen species (ROS) generation by 23%. Conversely, the generation of ROS in neutrophils exposed to the same field but stimulated by the bacterial peptide FMLP (N-formyl-L-methionyl-L-leucyl-L-phenylalanine) increased by about 21%. Pulsed magnetic fields also changed the rate of ROS generation in phorbol-stimulated neutrophils by about 20%, but the sign of the effects observed in this case was opposite to those induced by the magnetic field tuned to the parametric resonance for Ca²⁺ ions.     

The contractile vacuole in Ca2+-regulation in Dictyostelium: its essential function for cAMP-induced Ca2+-influx

Background  

cAMP-induced Ca²⁺-influx in Dictyostelium is controlled by at least two non-mitochondrial Ca²⁺-stores: acidic stores and the endoplasmic reticulum (ER). The acidic stores may comprise the contractile vacuole network (CV), the endosomal compartment and acidocalcisomes. Here the role of CV in respect to function as a potential Ca²⁺-store was investigated.