Titanium dioxide nanoparticles perturb the blood-testis barrier via disruption of actin-based cell adhesive function

• Published in: Aging (Albany, NY.) NY.), 2021-12, Vol.13 (23), p.25440-25452
• Main Authors: Ni, Dong-Qi, Ma, Dan-Dan, Hao, Shuang-Li, Yang, Wan-Xi, Kovacs, Tamas, Tan, Fu-Qing
• Format: Article
• Language: English
• Subjects: Actins - antagonists & inhibitors; Actins - metabolism; Animals; Blood-Testis Barrier - drug effects; Cell Adhesion - drug effects; Cell Line; Dose-Response Relationship, Drug; Male; Metal Nanoparticles - adverse effects; Mice; Research Paper; Sertoli Cells - drug effects; Sertoli Cells - metabolism; Tight Junction Proteins - metabolism; Titanium - adverse effects
• ISSN: 1945-4589; 1945-4589
• DOI: 10.18632/aging.203763

As one of the most commonly used nanoparticles, titanium dioxide nanoparticles (TiO -NPs) are widely used as coating reagents in cosmetics, medicine and other industries. The increasing risk of exposure to TiO -NPs raises concerns about their safety. In this study, we investigated the mechanism by which TiO -NPs cross the blood-testis barrier (BTB). TM-4 cells were selected as an Sertoli cell model of BTB. Cell viability, cell morphological changes, apoptosis, oxidative damage, and the expression levels of actin regulatory and tight junction (TJ) proteins were assessed in TM-4 cells treated with 3-nm and 24-nm TiO -NPs. Cells treated with 3-nm TiO -NPs exhibited increased cytotoxicity and decreased Annexin II expression, whereas cells treated with 24-nm TiO -NPs exhibited increased Arp 3 and c-Src expression. Both TiO -NPs induced significant oxidative stress, decreased the expression of TJ proteins (occludin, ZO-1 and claudin 5), damaged the TJ structure, and exhibited enlarged gaps between TM-4 cells. Our results indicated that both TiO -NPs crossed the BTB by disrupting actin-based adhesive junctions of TM-4 cells; however, apoptosis was not observed. Our results provide new insights into how TiO -NPs cross the BTB.