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An extremely low frequency magnetic field attenuates insulin secretion from the insulinoma cell line, RIN-m

Tomonori Sakurai1, Akira Satake, Shoichiro Sumi

  • 1Department of Organ Reconstruction, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.

Bioelectromagnetics
|March 26, 2004
PubMed

Insights

Extremely low frequency magnetic fields (ELFMF) significantly reduce insulin secretion from pancreatic cells. This effect is linked to reduced calcium influx and altered gene expression, suggesting ELFMF impacts hormone release mechanisms.

Area of Science:

  • Endocrinology
  • Cell Biology
  • Biophysics

Background:

  • Hormone secretion, particularly insulin, is crucial for metabolic regulation.
  • Extremely low frequency magnetic fields (ELFMF) are ubiquitous, and their biological effects warrant investigation.
  • Pancreatic beta-cells are responsible for insulin production and secretion.

Purpose of the Study:

  • To investigate the impact of ELFMF exposure on insulin secretion from an insulinoma cell line (RIN-m).
  • To elucidate the underlying mechanisms of ELFMF-induced changes in insulin release.

Main Methods:

  • RIN-m cells were exposed to a 5 mT, 60 Hz ELFMF or sham conditions for 1 hour.
  • Insulin secretion was stimulated using 45 mM KCl.
  • Effects of nifedipine on insulin secretion were assessed.
  • mRNA expression of SNAP-25 and synaptotagmin 1 was analyzed.

Main Results:

  • ELFMF exposure significantly attenuated insulin release compared to sham exposure.
  • Nifedipine treatment partially reversed the inhibitory effect of ELFMF on insulin secretion.
  • ELFMF exposure decreased the mRNA expression of SNAP-25 and synaptotagmin 1.

Conclusions:

  • ELFMF exposure attenuates insulin secretion from RIN-m cells.
  • The mechanism involves impaired calcium influx through calcium channels.
  • ELFMF affects key proteins involved in exocytosis and calcium signaling.

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