Neurotoxicity and related mechanisms of flame retardant TCEP exposure in mice

Abstract

Objective: To explore the neurotoxicity and mechanism of tris(2-chloroethyl) phosphate (TCEP) exposure in mice.

Methods: Total 30 adult Kunming mice were randomly divided into normal control group (0 mg/kg·d), low-dose TCEP group (10 mg/kg·d), and high-dose TCEP group (100 mg/kg·d), and administered continuously by gavage for 30 days.

Results: Compared with the control group, the water intake of high-dose TCEP group was declined significantly (p < 0.05), and the organ index of liver and spleen were increased significantly (p < 0.05). In addition, the escape latency of TCEP exposed mice were longer than that in the control group in water maze test (p < 0.05), while the total swimming course of high-dose TCEP group was elevated and the swimming time in target quadrant was obviously shortened compared with the control group (p < 0.05). The serum levels of total-triiodothyronine (TT3) and free triiodothyronine (FT3) were significantly higher in the high-dose TCEP group than in the control group (p＜0.05). Compared with the control group, the activities of glutathione transferase (GST) and super oxide dismutase (SOD) in the high-dose TCEP group were increased, and GST in the low-dose TCEP group were decreased, while the content of malonaldehyde (MDA) in both groups was increased (p＜0.05). In the CCK8 assay, the viability of PC12 cells decreased with an increase of TCEP concentration, indicating a concentration dependent neurotoxicity.

Conclusion: TCEP exposure can cause neurotoxicity by increasing thyroid hormones and inducing oxidative damage in mice.

Keywords:

• Organophosphate flame retardants
• TCEP
• learning memory
• thyroid hormones
• oxidative damage

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Disclosure statement

The authors report no declarations of interest.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [81860586], the Natural Science Foundation of Guangxi Province [2018GXNSFAA281054], and the Innovation and Entrepreneurship Training Program for College Students in Guangxi Province [201620601081, 201810601106, 201910601067].