Dosage-dependent induction of behavioral decline in Caenorhabditis elegans by long-term treatment of static magnetic fields.
The aim of this work was to explore the molecular mechanisms associated with possible health hazards induced by static magnetic fields (SMFs). Nematodes were grown under SMFs at field strengths from 0 to 200 mT, and the speed of body movement was measured. The effects of exposure to static magnetic fields were observed to be significant in the higher field strength and longer treatment. To explore the possible molecular mechanisms responsible for these effects, semi-quantitative real-time RT-PCR was performed using primers specific to 120 randomly selected genes. Twenty-six differentially expressed genes among apoptosis-, oxidative stress-, and cancer-related genes were identified, indicating that a global molecular response to SMF treatment occurred. The induction of apoptosis was verified by the increase of fluorescence in a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, by the caspase-3 activity assay, and by immunostaining using an antibody against the ced-3 gene product. Mutations in genes involved in major apoptotic pathways, that is, ced-3, ced-4, and ced-9, abolished this SMF-induced behavioral decline; this is consistent with the hypothesis that the apoptosis pathways are involved in the SMF-induced mobility decline. Here we show that long-term and low-dosage exposure to SMF is capable of inducing an apoptosis-mediated behavioral decline in nematodes.
Department of Material Science and Engineering, National Chiao Tung University, Taiwan, ROC.
Chia-Hui
CH
Lee
Huang-Meng
HM
Chen
Li-Ke
LK
Yeh
Meng-Yen
MY
Hong
Guewha Steven
GS
Huang
D000375:Aging / Q000235:genetics; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D017173:Caenorhabditis elegans / Q000502:physiology*; D029742:Caenorhabditis elegans Proteins / Q000096:biosynthesis / Q000235:genetics; D053148:Caspase 3 / Q000096:biosynthesis / Q000235:genetics; D015638:Cytochalasin D / Q000494:pharmacology; D005786:Gene Expression Regulation; D008124:Locomotion; D060526:Magnetic Fields / Q000009:adverse effects*; D009152:Mutagenicity Tests; D018384:Oxidative Stress / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
D029742:Caenorhabditis elegans Proteins; D015638:Cytochalasin D; D053148:Caspase 3