A Genome-Wide mRNA Expression Profile in Caenorhabditis elegans under Prolonged Exposure to 1750MHz Radiofrequency Fields

Abstract

ObjectiveC. elegans has been used as a biomonitor for microwave-induced stress. However, the RF (radiofrequency) fields that have been used in previous studies were weak (≤1.8W/kg), and the bio-effects on C. elegans were mostly negative or ambiguous. Therefore, this study used more intense RF fields (SAR = 3W/kg) and longer time course of exposure (60h at 25°C, L1 stage through adult stage) to investigate the biological consequences of 1750 MHz RF fields in wild-type worms.MethodsThe growth rates and lifespans of RF-exposure group and the control group were carefully recorded. RNA samples were collected at L4 (35h) and gravid adult (50h) stages for further high-throughput sequencing, focusing on differences between the RF-exposure and the sham control groups.ResultsThe RF-exposed and sham control groups developed at almost the same rate and had similar longevity curves. In L4 stage worms, 94 up-regulated and 17 down-regulated genes were identified, while 186 up-regulated and 3 down-regulated genes were identified in adult stage worms. GO analysis showed that the differentially expressed genes at 35h were associated with growth, body morphogenesis and collagen and cuticle-based development. Genes that were linked to growth rate and reproductive development were differentially expressed at 50h. Some embryonic and larval development genes in the offspring were also differentially expressed at 50h. Ten genes were differentially expressed at both 35h and 50h, most of which were involved in both embryonic and larval developmental processes. Although prolonged RF fields did not induce significant temperature increase in RF exposure groups, the temperature inside worms during exposure was unknown.ConclusionsNo harmful effects were observed in prolonged exposure to 1750 MHz RF fields at SAR of 3W/kg on development and longevity of C. elegans. Although some differentially expressed genes were found after prolonged RF exposure, these differences were ascribed to oscillating gene expression patterns in L4 and gravid adult worms. It was also difficult to rule out a weak thermal effect caused by prolonged RF exposure inside the worms.

Pulsed High‐Peak Power Microwaves at 9.4 GHz Do Not Affect Basic Endpoints in Caenorhabditis elegans

“…At present, the biological effects of microwaves on C. elegans have rarely been studied, and the results have been inconsistent [Bojjawar et al, 2006;Cucurachi et al, 2013;Fasseas et al, 2015;Shi et al, 2015;Gao et al, 2016;Sun et al, 2019]. One study investigated C. elegans exposed to 35 GHz millimeter waves with an average power of 1.52 W for 2-5 min.…”

“…It was found that millimeter waves could cause obvious damage as shown by slow growth and development in C. elegans [Gao et al, 2016]. However, the growth and development were significantly accelerated by microwave exposure at 0.9 and 1.75 GHz, respectively [Gao et al, 2016]. Gao also controlled the temperature consistency of the exposed group and the non-exposed group through the sXc-1800 exposure system.…”

“…One study investigated C. elegans exposed to 35 GHz millimeter waves with an average power of 1.52 W for 2-5 min. It was found that millimeter waves could cause obvious damage as shown by slow growth and development in C. elegans [Gao et al, 2016]. However, the growth and development were significantly accelerated by microwave exposure at 0.9 and 1.75 GHz, respectively [Gao et al, 2016].…”

Human Fibroblasts In Vitro Exposed to 2.45 GHz Continuous and Pulsed Wave Signals: Evaluation of Biological Effects with a Multimethodological Approach

“…To the best of our knowledge, only three in vivo studies evaluated the genome-wide mRNA expression profile using the Illumina sequencing technology, reporting differentially expressed genes in Caernorhabditis elegans after prolonged exposure to 1.75 GHz (SAR = 3 W/kg) [ 62 ] and in some genes related to energy metabolism in budding yeast after exposure to 50 Hz and 2.0 GHz [ 63 ]. A more recent study performed on Escherichia coli K-12 DH5α exposed to 2.4 GHz for 5 h reported that most of the genes identified were involved in many cellular and metabolic processes [ 64 ].…”

5 GHZ Wi Fi Effects on Escherichia Coli, Caenorhabditis Elegans and Human Neuroblastoma Cells

“…For C. elegans, which are exposed to non-thermal electromagnetic waves, induced some changes such as conformational damages to cellular proteins, opposite effects on growth and egg production[35]. In an opposite-minded research, after prolonged exposure to 1750 MHz RF fields, no effect was observed on longevity and development of C. elegans[36]. No significant differences were reported by another research group between exposed and sham exposed groups for lifespan, fertility, growth, memory, ROS, apoptosis or gene expression of C. elegans[37].…”