ILIJIN, LARISA et al. Biological effects of chronic exposure of Blaptica dubia (Blattodea: Blaberidae) nymphs to static and extremely low frequency magnetic fields. Anais da Academia Brasileira de Ciências [online]. 2021, v. 93, n. 2 [Accessed 11 June 2021] , e20190118. Available from: <https://doi.org/10.1590/0001-3765202120190118>. Epub 04 June 2021. ISSN 1678-2690. https://doi.org/10.1590/0001-3765202120190118.
In this paper, we analyzed the effects of chronic exposure (5 months) to static magnetic field (110 mT; SMF) and extremely low frequency magnetic field (ELF MF; 10 mT, 50 Hz) on Blaptica dubia nymphs. We have examined acetylcholinesterase (AChE) activity and heat shock protein 70 (HSP70) level, two sensitive biomarkers of stress in terrestrial insects. Relative growth rate (RGR), as a life history trait, was estimated. AChE activity was determined spectrophotometrically and HSP70 levels were quantified using indirect non-competitive ELISA and Western blotting. Calculated RGR was significantly changed upon exposure to both types of ambiental MFs. The effects of chronic exposure of B. dubia nymphs to SMF and ELF MF (50 Hz) were observed as decreased activity of AChE. The increased level of HSP70 was present only after exposure to SMF. The strength of ELF MF was most likely below the energy level needed to induce the expression of this stress protein. Different patterns of the expression of two HSP70 isoforms, where isoform 2 was sensitive only to SMF, are most likely a possibly switch – off in the expression of constitutive and/or inducible HSP70 isoforms.
The authors: “Our results provide an insight into the biological effects that chronic exposure to a strong SMF (110 mT) and ELF MF (10 mT, 50 Hz) have on the relative growth rate, AChE activity and HSP70 concentration in brain tissue of B. dubia nymph. These changes were probably a consequence of the different strengths of the ambiental MFs.”