Yibo Yu, Ke Yao, Wei Wu, Kaijun Wang, Guangdi Chen
Effects of exposure to 1.8 GHz radiofrequency field on the expression of Hsps and phosphorylation of MAPKs in human lens epithelial cells
Cell Research (2008) 18:1233–1235
Yibo Yu1, Ke Yao1,2, Wei Wu1, Kaijun Wang1, Guangdi Chen3 and Deqiang Lu3Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University and Ophthalmology Institute of Zhejiang University, Jiefang Road 88, Hangzhou 310009, China
Ophthalmology Institute of Zhejiang University, Hangzhou 310009, China
Bioelectromagnetic Laboratory, College of Medicine, Zhejiang University, Hangzhou 310009, ChinaCorrespondence: Ke Yao, Tel/Fax: +86-571-87783897 E-mail: firstname.lastname@example.org
There is evidence that induction of the MAPK pathway plays significant roles in the activation of specific Hsps. We thus examined the activation of MAPKs after exposure to RF at SARs of 2, 3, and 4 W/kg for 0, 5, 15, 30, 60, and 120 min. The results showed that ERK1/2 was markedly activated as early as 5 min after RF exposure; the activation peaked at 30 min and lasted up to 2 h after exposure. Phosphorylation of JNK1/2 was detected at 2 h after exposure, while p38 activation was not detected. Recently, it was reported that ERK was activated within 5 min of the radiation, with the peak activity occurring within 10-15 min, whereas no phosphorylation of JNKs or p38 was detected within a short time of exposure. Our results with human LECs are consistent with that study. These results indicate that mobile phone radiation can induce an immediate effect in the cytoplasm that activates ERK signaling so as to further induce transcription of a variety of genes, and that long exposure can activate JNK. However, we did not find the activation of p38 after RF exposure. The appearance of p-ERK1/2 and p-JNK1/2, together with Hsp up-regulation, suggests that non-thermal RF exposure can induce the stress response in human LECs.
Our results suggest that exposure to RF of wireless communications can induce expression of Hsp27 and Hsp70 and the activation of ERK1/2 and JNK1/2 in human LECs. The induction of Hsp27 and Hsp70, by a non-thermal stress, together with the activation of signal transduction pathways, provides reliable and sensitive biomarkers that could serve as the basis for improved mobile phone safety guidelines.