Lorentz forces induced by a static magnetic field have negligible effects on results from classical molecular dynamics simulations of aqueous solutions

Static magnetic field effects on the secondary structure and elasticity of collagen molecules; a possible biophysical approach to treat keratoconus

Type I collagen is among the major extracellular proteins that play a significant role in the maintenance of the cornea's structural integrity and is essential in cell adhesion, differentiation, growth, and integrity. Here, we investigated the effect of 300 mT Static Magnetic Field (300 mT SMF) on the structure and molecular properties of acid-solubilized collagens (ASC) isolated from the rat tail tendon. The SMF effects at molecular and atomic levels were investigated by various biophysical approaches like Circular Dichroism Spectropolarimetery (CD), Fourier Transform Infrared Spectroscopy (FTIR), Zetasizer light Scattering, and Rheological assay. Exposure of isolated type I collagen to 300 mT SMF retained its triple helix. The elasticity of collagen molecules and the keratoconus (KCN) cornea treated with SMF decreased significantly after 5 min and slightly after 10, 15, and 20 min of treatments. The exposure to 300 mT SMF shifted the Amid I bond random coil to antiparallel wave number from 1647 to 1631 cm-1. The pH of the 300 mT SMF treated collagen solution increased by about 25 %. The treatment of the KCN corneas with 300 mT SMF decreased their elasticity significantly. The promising results of the effects of 300 mT SMF on the collagen molecules and KCN cornea propose a novel biophysical approach capable of manipulating the collagen's elasticity, surface charges, electrostatic interactions, cross binding, network formation and fine structure. Therefore, SMF treatment may be considered as a novel non-invasive, direct, non-chemical and fast therapeutic and manipulative means to treat KCN cornea where the deviated physico-chemical status of collagen molecules cause deformation.

Impact of magnetic and electric fields on the free energy to form a calcium carbonate ion-pair

Electromagnetic fields are used in water treatment and desalination to regulate scale formation and extend the lifetime of membranes. External electric and magnetic fields can promote or suppress mineral nucleation and growth. However, the molecular-scale mechanisms of such processes remain unknown. Computing the free energies needed to form ion pairs under external fields provides important insights into understanding the elemental steps during the initial formation of mineral scales. In this paper, we used molecular dynamics combined with metadynamics simulations to investigate the free energies of forming the [Ca-CO3]0 ion pair, a fundamental building block of carbonate scales, under a range of magnetic (up to 10 T) and electric (up to 10 V m-1) fields in water. The presence of constant magnetic or electric fields favored the ion pairing reaction and lowered the free energies by up to 3% to 6%. The internal energy and entropic components of the free energy showed significant changes and exhibited non-linear behavior with increasing field strength. The [Ca-CO3]0 ion pairing is an entropy-driven process in the absence of an external field, but the mechanism shifts to an internal energy-driven process under selected external fields, suggesting possible changes in the nucleation pathways.

Phenolic acids and a static magnetic field change the expression of transforming growth factor β isoforms in amelanotic melanoma cells

BACKGROUND

Melanoma is an aggressive type of cancer that can metastasize to numerous other organs. TGFβ is one of the key signaling pathways in melanoma progression. Previous studies on various types of cancer have shown that both: polyphenols and a static magnetic field (SMF) can be potential chemopreventive/therapeutic agents. Therefore, the aim of the study was to evaluate the effect of a SMF and selected polyphenols on the transcriptional activity of TGFβ genes in melanoma cells.

METHODS AND RESULTS

Experiments were performed on the C32 cell line treated with caffeic or chlorogenic acids, and with simultaneous exposure to a moderate-strength SMF. The RT-qPCR method was used to determine the mRNA level of genes encoding the TGFβ isoforms and their receptors. The concentration of the TGFβ1 and TGFβ2 proteins were also measured in the cell culture supernates. The first response of C32 melanoma cells to both factors is the reduction of TGFβ levels. Then, mRNA level of these molecules returned to values close to pre-treatment level by the end of experiment.

CONCLUSION

Our study results demonstrate the potential of polyphenols and a moderate-strength SMF to support cancer therapy by altering TGFβ expression, which is a very promising topic for the diagnosis and treatment of melanoma.

Stability and Existence of Noncanonical I-motif DNA Structures in Computer Simulations Based on Atomistic and Coarse-Grained Force Fields

Cytosine-rich DNA sequences are able to fold into noncanonical structures, in which semi-protonated cytosine pairs develop extra hydrogen bonds, and these bonds are responsible for the overall stability of a structure called the i-motif. The i-motif can be formed in many regions of the genome, but the most representative is the telomeric region in which the CCCTAA sequences are repeated thousands of times. The ability to reverse folding/unfolding in response to pH change makes the above sequence and i-motif very promising components of nanomachines, extended DNA structures, and drug carriers. Molecular dynamics analysis of such structures is highly beneficial due to direct insights into the microscopic structure of the considered systems. We show that Amber force fields for DNA predict the stability of the i-motif over a long timescale; however, these force fields are not able to predict folding of the cytosine-rich sequences into the i-motif. The reason is the kinetic partitioning of the folding process, which makes the transitions between various intermediates too time-consuming in atomistic force field representation. Application of coarse-grained force fields usually highly accelerates complex structural transitions. We, however, found that three of the most popular coarse-grained force fields for DNA (oxDNA, 3SPN, and Martini) were not able to predict the stability of the i-motif structure. Obviously, they were not able to accelerate the folding of unfolded states into an i-motif. This observation must be strongly highlighted, and the need to develop suitable extensions of coarse-grained force fields for DNA is pointed out. However, it will take a great deal of effort to successfully solve these problems.

The Apoptotic Effect of Caffeic or Chlorogenic Acid on the C32 Cells That Have Simultaneously Been Exposed to a Static Magnetic Field

The induction of apoptosis is one of the main goals of the designed anti-cancer therapies. In recent years, increased attention has been paid to the physical factors such as magnetic fields and to the natural bioactive compounds and the possibilities using them in medicine. Hence, the aim of this study was to evaluate the anti-tumor effect of caffeic or chlorogenic acid in combination with a moderate-strength static magnetic field on C32 melanoma cells by assessing the effect of both factors on the apoptotic process. The apoptosis of the C32 cells was evaluated using a flow cytometry analysis. The expression of the apoptosis-associated genes was determined using the RT-qPCR technique. The caspase activity and the concentration of the oxidative damage markers were also measured. It was found that phenolic acids and a static magnetic field trigger the apoptosis of the C32 cells and also affect the expression of the genes encoding the apoptosis regulatory proteins. In conclusion, our study indicated that both of the phenolic acids and a static magnetic field can be used supportively in the treatment of melanoma and that caffeic acid is more pro-apoptotic than chlorogenic acid.

The effect of a static magnetic field and baicalin or baicalein interactions on amelanotic melanoma cell cultures (C32)

Background

Baicalin and baicalein have antioxidant, anti-inflammatory, hepatoprotective and anti-cancer properties. However, it is not known how a static magnetic field will modify these properties. Therefore, the aim of our study was to evaluate the simultaneous exposure of melanoma cells to flavones and the static magnetic fields that are generated by permanent magnets on the gene expression and the activity of the antioxidant enzymes that are associated with the antioxidant defense system.

Methods and results

Melanoma cells that had been treated with baicalin or baicalein were subjected to a static magnetic fields with a moderate induction. The static magnetic field was emitted by permanent magnets and the cell cultures were carried out in special test chambers. The research included determining the activity of the antioxidant enzymes (superoxide dismutase, glutathione peroxidase and catalase) as well as the gene expression profile. The addition of the flavones to the cell cultures at a concentration of 50 µmol/L resulted increase in the expression of the SOD1, SOD2 and GPX1 genes compared to the nontreated cell cultures. Simultaneous exposure of the melanoma cells to static magnetic field and baicalin or baicalein reduced their mRNA levels compared to the cultures to which only baicalin or baicalein had been added. The change in gene expression was accompanied by changes at the protein level associated with an increase in the activity of antioxidant enzymes.

Conclusion

We showed that baicalin or baicalein have anticancer properties by disturbing the redox homeostasis in melanoma cells and also increases the antioxidant system gene expression. There was also an antagonistic interaction between the studied flavones and the static magnetic field, which cause a decrease in the anticancer effects of baicalin or baicalein.

Retracted Article: Boric acid in magnetized water: clean and powerful media for synthesis of 3,4-dihydropyrimidin-2(1H)-ones

Water was magnetized via an external magnetic field and employed, for the first time, as a solvent in green preparation of 3,4-dihydropyrimidin-2(1H)-ones by the one-pot three-component condensation reaction using boric acid as a catalyst. Shorter reaction times, higher yields, and cleaner reaction profiles were some advantages of using magnetic water.