We have located links that may give you full text access.
Titanium dioxide nanoparticles induce COX-2 expression through ROS generation in human periodontal ligament cells.
Titanium dioxide nanoparticles (TiO2 -NPs) are used to improve the aesthetic of toothpaste. While TiO2 -NPs have been used safely in toothpaste products for a long time, there haven't been studies to determine whether absorption of TiO2 -NPs by the mucous membranes in the mouth induces pathogenic conditions. Here, we assessed whether TiO2 -NPs induce cyclooxygenase-2 (COX-2) and investigated the molecular mechanisms underlying the pro-inflammatory effect of TiO2 -NPs on human periodontal ligament (PDL) cells. Treatment of PDL cells with TiO2 -NPs led to induction of both COX-2 mRNA and protein expression. TiO2 -NPs stimulated the nuclear translocation of nuclear factor-kappaB (NF-κB) as well as its DNA binding by inducing phosphorylation and subsequent degradation of the inhibitory protein IκBα in PDL cells. TiO2 -NPs treatment resulted in rapid activation of extracellular signal-regulated kinase (ERK)1/2 and Akt, which could be upstream of NF-κB. Treatment of PDL cells with both the MEK1/2 inhibitor U0126 and the PI3K inhibitor LY294002 strongly attenuated TiO2 -NPs-induced activation of NF-κB, and also the expression of COX-2. PDL cells treated with TiO2 -NPs exhibited increased accumulation of intracellular reactive oxygen species (ROS). Pretreatment of cells with ROS scavenger N-acetyl cysteine (NAC) abrogated the stimulatory effect of TiO2 -NPs on p65, p50, and COX-2 expression. In conclusion, ROS, concomitantly overproduced by TiO2 -NPs, induce COX-2 expression through activation of NF-κB signaling, which may contribute to the inflammatory effect of PDL cells.
Full text links
Related Resources
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app