# Forchlorfenuron Exposure Induces Hepatocyte Apoptosis via MKK3/P38/ATF2 Pathway

## TL;DR

This study shows that forchlorfenuron, a plant growth regulator, can damage liver cells by triggering cell death through a specific signaling pathway.

## Contribution

The study identifies the MKK3/P38/ATF2 pathway as a novel mechanism of hepatocyte apoptosis caused by forchlorfenuron exposure.

## Key findings

- Forchlorfenuron reduces HepaRG cell viability in a concentration- and time-dependent manner.
- Forchlorfenuron induces apoptosis and oxidative stress in hepatocytes.
- Inhibition of the P38 pathway reduces apoptosis, implicating MKK3/P38/ATF2 in hepatotoxicity.

## Abstract

Forchlorfenuron is a widely used plant cytokinin in Traditional Chinese Medicine and agricultural cultivation to boost resistance, postpone senescence, and increase productivity. However, the improper use of forchlorfenuron results in excessive residues and contamination, raising health and safety concerns. Our research investigated the toxicity of forchlorfenuron on hepatocytes in vitro. Results showed that forchlorfenuron inhibited HepaRG cell viability in a concentration and time-dependent manner. Forchlorfenuron-induced cellular apoptosis and the increased intracellular reactive oxygen species (ROS) indicated the participation of oxidative stress. Molecular docking and network pharmacology data suggested that the hepatotoxicity of forchlorfenuron might involve the MAPK signaling pathway. After 24 h of forchlorfenuron exposure, the P38-MAP kinase, upstream kinases MKK3, and the transcription factor ATF2 were maximally activated. Apoptosis induced by forchlorfenuron was significantly reduced by pretreatment with the P38 inhibitor SB203580. These findings implicated that HepaRG hepatocyte injuries were generated by forchlorfenuron through the induction of cellular apoptosis via the MKK3/P38/ATF2 pathway. Forchlorfenuron application should be closely managed to prevent potential liver damage.