Conclusion
Overall, our findings demonstrate that ADMSC-CDVs have potent radioprotective effects on irradiated SG cells.
Methods
The artificial CDVs were obtained from ADMSC by tangential flow filtration (TFF) purification and ultracentrifugation. Cultured human SG epithelial cells were exposed to 2, 5 or 15 Gy of 4 MV X-rays produced by a linear accelerator. The effects of ADMSC-CDVs on SG epithelial cells damaged by irradiation were tested by proliferation activity, transepithelial electrical resistance (TEER), and amylase activity.
Results
Exposure to penetrating radiation inhibited the proliferation of SG epithelial cells, but the radiation intensity required to reduce the proliferation of human submandibular gland epithelial cells (hSMGECs) was greater than required for other SG cells. ADMSC-CDVs restored the proliferative ability of SG epithelial cells reduced by irradiation, and the proliferation capacities of irradiated human parotid gland epithelial cells (hPGECs) and human sublingual gland epithelial cells (hSLGECs) were increased by administering ADMSC-CDVs to non-irradiated SG epithelial cells. Furthermore, amylase activity in irradiated hPGECs, hSMGECs, and hSLGECs was lower than in non-irradiated controls. However, amylase ability was restored in all by ADMSC-CDV treatment. Also, TEER was diminished by irradiation in hPGECs, hSMGECs, and hSLGECs and restored by ADMSC-CDV administration.