Mice were depilated at dorsal skin and divided at random into a control group and exposure group (sizes of groups not mentioned). After 3, 9 and 16 days of exposure, 3 animals per group were investigated, respectively. The experiment was repeated 3 times. (remark EMF-Portal: A total of 27 animals per experiment, which is mentioned in the article, is not comprehensible.)
Exposure duration: 30 minutes per day for up to 16 days
|magnetic flux density||5 mT||-||-||-||-|
The histological analysis showed that hair follicle growth was increased in the exposure group compared to the control group at all time points. The hair lenght was significantly increased in the exposure group compared to the control group after 16 days. Moreover, immunohistochemical staining revealed increased cell proliferation in the outer root sheath and hair bulb in the exposure group compared to the control group at all time points where it was co-localized with epidermal stem cells. Keratinocyte growth factors were expressed in the inner root sheath in both groups, and in Western Blot, the exposure group showed a higher expression rate at all time points than the control group (significance unclear).
The authors conclude that exposure of mice to a 50 Hz magnetic field could promote hair follicle regrowth in association with stem cells proliferation and increased keratinocyte growth factor expression.