RESUMO
Objective:To investigate the effect of radiofrequency radiation (RF) from 5G mobile phone communication frequency bands (3.5 GHz and 4.9 GHz) on the permeability of the blood-brain barrier (BBB) in mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into Sham, 3.5 GHz RF and 4.9 GHz RF groups, and 8 mice in each group. Mice in the RF groups were systemically exposed to 5G cell phone radiation for consecutive 35 d(1 h/d) with 50 W/m 2 power density. The BBB permeability of mice was detected by Evans Blue (EB) fluorescence experiment. The expression levels of the BBB tight junction-related proteins (ZO-1, occludin and claudin-11) and the gap junction-related protein Connexin 43 were determined by Western blot. Results:The number of spots, fluorescence intensity and comprehensive score of EB were significantly increased in 3.5 GHz RF group and 4.9 GHz RF group compared with the Sham group ( t=12.98, 17.82, P<0.001). Compared with the Sham group, the content of S100B in mouse serum was significantly increased in 3.5 GHz RF group and 4.9 GHz RF group ( t=19.34, 14.68, P<0.001). The BBB permeability was increased in the RF group. The expression level of occludin protein was significantly reduced in the 3.5 GHz RF group ( t=-3.13, P<0.05), and this decrease was much profound in the 4.9 GHz RF group ( t=-6.55, P<0.01). But the protein levels of ZO-1, Claudin-11 and Connexin 43 in the cerebral cortex of the RF groups had no significantly difference in comparison with the Sham group( P>0.05). Conclusions:The continuous exposure of mobile phone RF at 3.5 GHz or 4.9 GHz for 35 d (1 h/d) induces an increase of BBB permeability in the mouse cerebral cortex, perhaps by reducing the expression of occludin protein.
RESUMO
Objective:To investigate the effect of thoracic X-ray irradiation on the spermatogenesis of adult male mice.Methods:A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into radiation group (Radiation) and sham-radiation group (Sham), 12 mice in each group. The area of thoracic irradiation was 1.5 cm× 2 cm, and the dose rate was 3.04 Gy/min, 8 Gy/d for 3 consecutive days, 24 Gy in total. At 7 d and 21 d after thoracic irradiation, the bilateral testes and epididymal tails were stripped and the testicular index was calculated. The morphology of testis was examined by haematoxylin-eosin (HE) staining, then the diameter of seminiferous tubules and the thickness of seminiferous epithelium were measured. The sperms were collected from the bilateral epididymal tails for sperm counting. The level of apoptosis in testis and levels of apoptosis-related proteins were detected by TUNEL and Western blot, respectively.Results:Compared with Sham group, the morphology of testis and epididymis was seriously damaged, the diameter of seminiferous tubules significantly decreased at 21 d after irradiation ( t = 8.93, P < 0.05), and the seminiferous epithelium significantly decreased at 7 d and 21 d after irradiation ( t = 4.24, 12.77, P < 0.05). In addition, the number of sperms significantly decreased ( t = 4.30, 2.98, P < 0.05). The number of TUNEL positive cells in the seminiferous epithelium significantly increased at 7 d and 21 d after irradiation ( t = -2.73, -3.74, P < 0.05). Meanwhile, the level of cleaved Caspase-3 protein significantly increased at 7 d and 21 d after irradiation ( t = -2.96, -2.46, P < 0.05). The concentrations of SCF and GDNF did not change at 7 d after irradiation, but were significantly increased at 21 d after irradiation ( t = -10.46, -5.42, P < 0.05). Conclusions:The thoracic X-ray irradiation could lead to spermatogenesis disorder in male adult mice, and the induction of spermatogenic cell apoptosis and the secretory dysfunction of sertoli cells may be involved.