The effects of electromagnetic pulses (EMP) on the bioactivity of insulin and a preliminary study of mechanism

Abstract

Purpose: To investigate the effects of electromagnetic pulse (EMP) exposure on the bioactivity of insulin and a preliminary mechanism for these effects.

Materials and methods: A tapered parallel plate Gigahertz Transverse Electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose the insulin solution to EMP. Concurrent sham-exposed insulin solutions were used as a control. The effect of EMP-exposed insulin on fasting blood glucose levels of type I diabetes model mice, the effect of EMP on binding affinity between insulin and its receptor and the effect of EMP on insulin's fluorescence intensity were detected, respectively.

Results: (i) After EMP exposure, compared with sham-exposed insulin, the bioactivity of insulin in decreasing fasting blood glucose levels in type I diabetes model mice was reduced significantly (p = 0.023). (ii) Compared with sham-exposed insulin group, the percentage fluorescein isothiocyannate (FITC) labelling of HL-7702 cells was significantly reduced in the EMP-exposed insulin group (22.7–13.8%, respectively). (iii) Compared with sham-exposed insulin, the fluorescence intensity was significantly reduced in EMP-exposed insulin (p < 0.001).

Conclusions: EMP exposure significantly decreased the bioactivity of insulin to reduce the blood glucose levels in type I diabetic mice. This could be due to a decreased binding affinity between insulin and its receptor. This mechanism could involve an alteration of insulin's' conformation caused by EMP exposure.

Keywords:

• electromagnetic pulse (EMP)
• insulin
• bioactivity
• binding affinity
• conformation

Acknowledgements

The funding for this study was provided by the National Science Foundation of China (No. 60601026; No. 30570447; No. 60871068; No. 30700660) and National 863 Project of China (No. 2008AA803421B).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.