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Electromagnetic Fields in Biological Systems
in S-phase processes and occasional triggering of apoptosis rather than by the generation of DNA damage.
Jimenez-Garcia et al. (2010) found that the application of an ELF-EMF (120 Hz,
4.5 mT) inhibits chemically induced preneoplastic lesions in the rat liver through the
reduction of cell proliferation, without altering the apoptosis process. Monache et al.
(2008) investigated the effect of an ELF-EMF (50 Hz, 1 mT, for 12 hours) on the activation of angiogenesis in cultured umbilical HUVECs. The EMF exposure increased the
degree of endothelial cell proliferation and tubule formation and accelerated the process
of wound healing. The EMF exposure induced a major reorganization of fibers and of
focal adhesion complexes, and increased phosphorylation as well as the overall expression of VEGF receptor 2 (KDR/Flk-1). The authors suggested that EMF may modulate in
vitro some endothelial functions correlated to angiogenesis through signal transduction
pathways dependent on VEGF.
The same research group also reported that the exposure of human spermatozoa to
an ELF-EMF (50 Hz, 5 mT) improves sperm motility (Iorio et al. 2011). The ELF-EMF
exposure resulted in a progressive and significant increase in mitochondrial membrane
potential and in the levels of ATP, ADP, and NAD + measured as sperm kinematic parameters. No significant effects were detected on other parameters such as ATP to ADP
ratio and energy charge. When carbamoyl cyanide m-chlorophenylhydrazone (CICCP)
was applied to inhibit the oxidative phosphorylation in the mitochondria, the values
of energy parameters and motility in the sperm incubated in the presence of glucose
and exposed to ELF-EMF did not change, indicating that glycolysis was not involved
in mediating the ELF-EMF stimulatory effect on motility. In contrast, when pyruvate
and lactate were provided instead of glucose, the energy status and motility increased
significantly in ELF-EMF-treated sperm. Under these culture conditions, the inhibition of glycolytic metabolism by 2-deoxy-D-glucose (DOG) again resulted in increased
values of energy and kinematic parameters, indicating that gluconeogenesis was not
involved in producing glucose for use in glycolysis. The authors concluded that the key
role in mediating the stimulatory effects exerted by ELF-EMF on human sperm motility
is played by mitochondrial oxidative phosphorylation rather than glycolysis.
Garip and Akan (2010) investigated the effect of an ELF-EMF (50 Hz, 1 mT) on the
number of apoptotic cells in human leukemia cells (K562) that are or are not induced
with oxidative stress and the correlation with HSP70 levels. One sample was treated with
H 2 O 2 and the other was left untreated. Exposure to ELF-EMF alone for 3 hours caused
a decrease in the number of apoptotic cells and a slight increase in viability. However,
it increased the number of apoptotic cells. In cells treated with H 2 O 2 , HSP70 and ROS
levels were increased by exposure to ELF-EMF. These results showed that the effect of
ELF-EMF on biological systems depends on the status of the cell: Whereas in cells not
exposed to oxidative stress ELF-EMF is able to decrease the number of apoptotic cells by
inducing an increase in HSP levels, it increases the number of apoptotic cells in oxidative stress–induced cells.
Polaniak et al. (2010) examined the effects of vitamin E, an ELF-EMF (400 Hz, 0.11 mT,
130 V/m, for 16 minutes), and their combination in different time intervals of exposure
of vitamin E on the AT478 murine squamous cell carcinoma line. Following vitamin E
treatment, activity of antioxidant enzymes increased compared with the control group.
Electromagnetic Fields in Biological Systems
in S-phase processes and occasional triggering of apoptosis rather than by the generation of DNA damage.
Jimenez-Garcia et al. (2010) found that the application of an ELF-EMF (120 Hz,
4.5 mT) inhibits chemically induced preneoplastic lesions in the rat liver through the
reduction of cell proliferation, without altering the apoptosis process. Monache et al.
(2008) investigated the effect of an ELF-EMF (50 Hz, 1 mT, for 12 hours) on the activation of angiogenesis in cultured umbilical HUVECs. The EMF exposure increased the
degree of endothelial cell proliferation and tubule formation and accelerated the process
of wound healing. The EMF exposure induced a major reorganization of fibers and of
focal adhesion complexes, and increased phosphorylation as well as the overall expression of VEGF receptor 2 (KDR/Flk-1). The authors suggested that EMF may modulate in
vitro some endothelial functions correlated to angiogenesis through signal transduction
pathways dependent on VEGF.
The same research group also reported that the exposure of human spermatozoa to
an ELF-EMF (50 Hz, 5 mT) improves sperm motility (Iorio et al. 2011). The ELF-EMF
exposure resulted in a progressive and significant increase in mitochondrial membrane
potential and in the levels of ATP, ADP, and NAD + measured as sperm kinematic parameters. No significant effects were detected on other parameters such as ATP to ADP
ratio and energy charge. When carbamoyl cyanide m-chlorophenylhydrazone (CICCP)
was applied to inhibit the oxidative phosphorylation in the mitochondria, the values
of energy parameters and motility in the sperm incubated in the presence of glucose
and exposed to ELF-EMF did not change, indicating that glycolysis was not involved
in mediating the ELF-EMF stimulatory effect on motility. In contrast, when pyruvate
and lactate were provided instead of glucose, the energy status and motility increased
significantly in ELF-EMF-treated sperm. Under these culture conditions, the inhibition of glycolytic metabolism by 2-deoxy-D-glucose (DOG) again resulted in increased
values of energy and kinematic parameters, indicating that gluconeogenesis was not
involved in producing glucose for use in glycolysis. The authors concluded that the key
role in mediating the stimulatory effects exerted by ELF-EMF on human sperm motility
is played by mitochondrial oxidative phosphorylation rather than glycolysis.
Garip and Akan (2010) investigated the effect of an ELF-EMF (50 Hz, 1 mT) on the
number of apoptotic cells in human leukemia cells (K562) that are or are not induced
with oxidative stress and the correlation with HSP70 levels. One sample was treated with
H 2 O 2 and the other was left untreated. Exposure to ELF-EMF alone for 3 hours caused
a decrease in the number of apoptotic cells and a slight increase in viability. However,
it increased the number of apoptotic cells. In cells treated with H 2 O 2 , HSP70 and ROS
levels were increased by exposure to ELF-EMF. These results showed that the effect of
ELF-EMF on biological systems depends on the status of the cell: Whereas in cells not
exposed to oxidative stress ELF-EMF is able to decrease the number of apoptotic cells by
inducing an increase in HSP levels, it increases the number of apoptotic cells in oxidative stress–induced cells.
Polaniak et al. (2010) examined the effects of vitamin E, an ELF-EMF (400 Hz, 0.11 mT,
130 V/m, for 16 minutes), and their combination in different time intervals of exposure
of vitamin E on the AT478 murine squamous cell carcinoma line. Following vitamin E
treatment, activity of antioxidant enzymes increased compared with the control group.