The potential mechanism underlying the hepatorenal toxicity induced by hymexazol in rats and the role of NF-kappa B signaling pathway

Hymexazol (HML) is widely used in agriculture as a systemic fungicide and plant growth promoter. Humans are continuously exposed to HML via various routes. The liver and kidneys are essential organs for the detoxification, metabolism, and excretion of HML. However, data concerning the impact of HML on nontarget organisms are scarce. The present study aimed to determine the mechanism of dose-dependent hepatorenal toxicity of HML in rats. Twenty-one rats were divided into three equal groups that received the following treatments via oral intake daily for 14 days: group 1, normal saline; group 2, low dose of HML (1/80 LD50); group 3, high dose of HML (1/40 LD50). We weighed the rats at the beginning and the end of the experiment to record the weight gain in each group. The results showed that HML induced dose-dependent hepatorenal toxicity manifested by a significant increase in malondialdehyde levels, a decrease in total antioxidant capacity and reduced glutathione contents, and upregulation of the transcriptase levels of the nuclear factor kappa B (NF-kappa B), tumor necrosis factor alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta) genes. The HML-exposed groups displayed various histopathological changes in both organs, with significant elevation of all serum liver and kidney biomarkers. In conclusion, HML produced hepatorenal toxicity in rats through oxidative stress that mediates the NF-kappa B signaling pathway in response to pro-inflammatory cytokines such as TNF-alpha and IL-1 beta. We advise limiting the use of HML in agricultural and veterinary practices and finding an alternative agent to avoid the human and animal health risks induced by HML exposure.