Effect of high-frequency electromagnetic fields on trophoblastic connexins.
Connexins (Cx) are membrane proteins able to influence trophoblast functions. Here we investigated the effect of high-frequency electromagnetic fields (HF-EMF) on Cx expression and localization in extravillous trophoblast cell line HTR-8/SVneo. We also analysed cell ultrastructural changes induced by HF-EMF exposure. Samples were exposed to pulse-modulated 1817 MHz sinusoidal waves (GSM-217 Hz; 1h: SAR of 2 W/kg). Cx mRNA expression was assessed through semi-quantitative RT-PCR, protein expression by Western blotting, protein localization by indirect immunofluorescence, cell ultrastructure using electron microscopy. HF-EMF exposure significantly and selectively increased Cx40 and Cx43, without altering protein expression. Nevertheless, Cx40 and Cx43 lost their punctuate fluorescence within the cell membrane, becoming diffuse after HF-EMF exposure. Electron microscopy evidenced a sharp decrease in intercellular gap junction-like structures. This study is the first to indicate that exposure of extravillous trophoblast to GSM-217 Hz signals can modify Cx gene expression, Cx protein localization and cellular ultrastructure.
Cervellati
Franco
F
Department of Biology and Evolution, Section of General Physiology, University of Ferrara, via L. Borsari 46, 44100 Ferrara, Italy.
Franceschetti
Guido
G
Lunghi
Laura
L
Franzellitti
Silvia
S
Valbonesi
Paola
P
Fabbri
Elena
E
Biondi
Carla
C
Vesce
Fortunato
F
D015153:Blotting, Western; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D018031:Connexin 43 / Q000378:metabolism; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D004574:Electromagnetic Fields; D005455:Fluorescent Antibody Technique; D017629:Gap Junctions / Q000378:metabolism / Q000528:radiation effects* / Q000648:ultrastructure; D006801:Humans; D046529:Microscopy, Electron, Transmission; D021381:Protein Transport; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014327:Trophoblasts / Q000378:metabolism / Q000528:radiation effects* / Q000648:ultrastructure; D000097003:Gap Junction alpha-5 Protein
D018031:Connexin 43; D017630:Connexins; D000242:Cyclic AMP; D012333:RNA, Messenger; D000097003:Gap Junction alpha-5 Protein; C500216:GJA1 protein, human