Development of an antibody technique for acetylcholinesterase expression detection in the gill of Nile tilapia (Oreochromis niloticus) as a glyphosate-based herbicide biomarker

Phochit Nanthanawat; Pongpat Kiatprasert; Amnuay Wattanakornsiri; Jakkaphun Nanuam; Witchuda Prasatkaew; Sawipa Ruttanakorn; Chutima Thanomsit

doi:10.1016/j.toxrep.2022.07.009

Development of an antibody technique for acetylcholinesterase expression detection in the gill of Nile tilapia (Oreochromis niloticus) as a glyphosate-based herbicide biomarker

Toxicol Rep. 2022 Jul 13:9:1548-1556. doi: 10.1016/j.toxrep.2022.07.009. eCollection 2022.

Authors

Phochit Nanthanawat¹, Pongpat Kiatprasert², Amnuay Wattanakornsiri³, Jakkaphun Nanuam⁴, Witchuda Prasatkaew⁵, Sawipa Ruttanakorn⁶, Chutima Thanomsit⁷

Affiliations

¹ Department of Biotechnology, Faculty of Science, Burapha University, Chonburi 20131, Thailand.
² Department of Science and Mathematics, Faculty of Agriculture and Technology, Rajamangala University of Technology Isan Surin Campus, Surin 32000, Thailand.
³ Department of Agriculture and Environment, Faculty of Science and Technology, Surindra Rajabhat University, Surin 32000, Thailand.
⁴ Program of Natural Resources and Environment, Faculty of Science and Social Sciences, Burapha University, Sakaeo, Thailand.
⁵ Department of Environmental Management, Faculty of Science and Technology, Dhonburi Rajabhat University, Samutprakan 10540, Thailand.
⁶ Department of Fishery Technology, Faculty of Agricultural Technology, Kalasin University, Kalasin 46000, Thailand.
⁷ Department of Fisheries, Faculty of Agriculture and Technology, Rajamangala University of Technology Isan Surin Campus, Surin 32000, Thailand.

Abstract

Widely used glyphosate-based herbicides can remain in agricultural fields or be spread into the surrounding environment. This study aimed to develop an antibody technique for assessing acetylcholinesterase (AChE) expression in Nile tilapia (Oreochromis niloticus) after glyphosate exposure in the assessed tissues consisting of plasma, muscle, gills, and liver. Results showed that the cumulative mortality of fish exposed to glyphosate increased with exposure time and glyphosate concentration. The LC₅₀ was evaluated using probit analysis. A sub-lethal concentration of 2 µL L^-1 glyphosate-based herbicide altered behavioural and physiological appearances. AChE expression decreased compared to that in the control group with increasing glyphosate exposure time. The 71 kDa AChE was consecutively expressed in plasma, muscle, gill, and liver under laboratory and field conditions, as detected by dot blot and Western blot analysis. Furthermore, laboratory and field studies of the gills showed positive immunohistochemical results. Although this study could detect AChE expression in many tissues, using gills to assess AChE exposure allowed the fish not to be sacrificed compared with other organ studies, and this technique can be used in both laboratory and field conditions. In conclusion, the antibody technique can be applied to measure AChE expression in the gill tissue to assess glyphosate-based herbicide exposure.

Keywords: Acetylcholinesterase; Exposure; Glyphosate; Herbicide; Probit analysis.