この研究は、著者らの先行研究で磁界（1.5 mT、60 Hz）の影響が観察されたヒトケラチノサイト細胞株HaCaTに代えて、別のヒトケラチノサイト細胞株である正常ヒト表皮ケラチノサイト細胞株NHEKを用いて同じ実験デザインで実験した。その結果、細胞の成長、増殖、細胞周期分布、ATM信号伝達経路の活性化への影響が何も観察されなかった。この2種類の細胞株で磁界の影響が異なることを確認するため、同じ培養器内においてHaCaTとNHEKに同時に磁界ばく露した結果、細胞成長への影響が異なった､と報告している。
The detailed summary of this article is not available in your language or incomplete. Would you like to see a complete translation of the summary? Then please contact us →
To investigate whether extremely low frequency magnetic fields influence the cell cycle in normal epidermal keratinocytes.
In a previous study, the authors found that extremely low frequency magnetic fields caused a cell cycle arrest potentially through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells (Huang et al.).
Ionizing radiation (UV-B, 21.5 J/m²) was performed as a positive control. Cell proliferation and cell viability experiments were additionally performed with HaCaT cells.
ばく露時間: continuous up to 144 hours (24, 48, 72, 96, 120, 144 hours)
|ばく露時間||continuous up to 144 hours (24, 48, 72, 96, 120, 144 hours)|
|ばく露装置の詳細||coil system generated a uniform 1.5 mT magnetic field; temperature inside the incubator was 36.9 ± 0.3°C|
|Sham exposure||A sham exposure was conducted.|
|Additional information||all sham exposed cells were cultured in a chamber magnetically shielded using a mumetal box in the same incubator in which the exposed cells were incubated|
Extremely low frequency magnetic fields do not influence cell proliferation, cell viability, cell cycle distribution as well as gene expression and protein expression in keratinocytes derived from neonatal foreskin when compared to sham exposure. However, cell proliferation and cell viability were significantly decreased in exposed HaCaT cells in comparison to sham exposed ones. Moreover, an additional experiment with simultaneous exposure of the two cell lines showed that the keratinocytes derived from neonatal foreskin and the HaCaT cells exhibited distinct responses to the magnetic field.
The authors conclude that the biological effects of extremely low frequency magnetic fields are cell type specific. These findings could present an explanation for the inconsistent results in previous studies using various experimental models.