The adoption of triazole fungicides has significantly increased in modern agriculture due to their high efficacy, low application rates, and relatively favorable environmental profiles compared to traditional classes of fungicides. However, the triazole fungicides have been detected in a variety of food products, beverages, and human biomonitoring studies. Given the widespread human exposure to these compounds, comprehensive investigations are needed to evaluate their potential safety hazards [23, 24].
In our study, we integrated a comprehensive approach utilizing network toxicology, molecular docking, and multi-layered bioinformatics to explore the effects of exposure to the triazole fungicides HA, PP, and PT on the brain and liver, as well as their potential mechanisms of action. After applying network-based computational assessment tools, we identified potential targets associated with brain or liver damage induced by HA, PP, and PT using the ChEMBL, Swiss Target Prediction, GeneCards, OMIM, and DisGeNet databases. Utilizing the STRING database and Cytoscape software, we constructed an interaction network for these potential targets and extracted core targets, including EGFR, CASP3, ESR1, PPARG, TP53, HSP90AA1, and PTGS2. These targets were designated as critical for the induction of brain or liver damage by the three triazole fungicides.
Epidermal growth factor receptor (EGFR), a transmembrane receptor tyrosine kinase, plays an important role in maintaining normal tissue and cell signaling pathways [25]. Dysregulation of EGFR has been implicated in neurodegenerative diseases, where altered signaling pathways contribute to neuronal apoptosis and cognitive decline [26]. EGFR signaling plays a central role in the regenerative response after liver injury and is involved in cell transformation associated with chronic injury [27]. In addition, studies have shown that EGFR is also associated with apoptotic cell death signaling in various hepatocytes, mitochondrial dysfunction, and acute liver necrosis [28].
Caspase-3 (CASP3), a widely expressed member of the conserved protein family, plays a key role in regulating the growth and homeostasis maintenance of normal and malignant cells and tissues in multicellular organisms [29]. Activation of CASP3 is strongly associated with neurodegenerative diseases and traumatic brain injury, and its upregulation leads to neuronal apoptosis, exacerbating cognitive decline and dysfunction [30, 31]. CASP3 mediates hepatocyte apoptosis in response to hepatotoxic substances, leading to liver damage and fibrosis, cirrhosis and other conditions [32]. The study suggests that modulating CASP3 activity may provide a therapeutic pathway for alleviating cell death in brain and liver injury [33].
Estrogen receptor alpha (ESR1) is a key regulator that regulates the effects of estrogen on a variety of tissues, including the brain and liver [34]. Studies have shown that ESR1 signaling has a neuroprotective effect, as estrogen can enhance neuronal survival and reduce apoptosis after trauma or ischemic injury [35]. And ESR1 activation is associated with improved cognitive function and reduced neuroinflammation [36]. In liver injury, ESR1 plays a complex role in promoting liver cell regeneration and preventing oxidative stress [37]. However, dysregulated ESR1 signaling can contribute to the progression of liver diseases, including fatty liver and fibrosis [38].
Peroxisome proliferator activating receptor (PPARG) is a nuclear receptor that regulates genes involved in lipid metabolism, inflammation, and insulin sensitivity [39]. Activation of PPARG has been shown to have neuroprotective effects, enhancing neuronal survival and reducing neuroinflammation after trauma or ischemic injury [40]. Studies have shown that activating PPARG can improve cognitive outcomes and promote repair mechanisms in neurodegenerative diseases [41]. In addition, PPARG plays a key role in lipid homeostasis and inflammation resolution [42]. Activation of PPARG is associated with a reduction in steatosis and fibrosis in various liver diseases [43].
The TP53 gene encodes the tumor suppressor protein p53, which plays a crucial role in cellular stress responses, including apoptosis, cell cycle regulation, and DNA repair [44]. In brain injury, activation of TP53 is often associated with neurodegenerative diseases, and in response to oxidative stress and DNA damage, it mediates neuronal apoptosis, leading to cognitive decline and neuron loss [45]. In liver injury, p53 can promote apoptosis of damaged liver cells and prevent tumorigenesis, but excessive activation can lead to chronic inflammation and fibrosis [46].
The HSP90AA1 gene encodes heat shock protein 90α (Hsp90), an important companion involved in protein folding and cellular stress response [47]. Previous studies have shown that Hsp90 exhibits neuroprotective properties, promoting the stabilization of client proteins and preventing neuronal cell apoptosis during ischemic or traumatic events [48]. On the other hand, Hsp90 plays an important role in maintaining the integrity of hepatocytes under stress conditions such as oxidative damage and inflammation [49].
The enzyme protein prostaglandin-endoperoxide synthase 2 (PTGS2) is involved in inflammation and other physiological processes by catalyzing the conversion of arachidonic acid to prostaglandin [50]. For brain injury, COX-2 expression is upregulated in response to neuronal injury, leading to neuroinflammation and pain [51]. While COX-2 is involved in protective mechanisms that promote healing and regeneration, overactivation can exacerbate neuronal damage and lead to chronic neurodegenerative diseases [51]. For liver damage, PTGS2 is involved in the inflammatory response associated with liver disease, including non-alcoholic fatty liver disease and hepatitis [52]. Elevated COX-2 levels are associated with increased inflammation and apoptosis of liver cells, which worsens liver damage [53].
Pathway analysis highlights key insights into the molecular mechanisms of brain and liver injury induced by triazole fungicides. The significant enrichment of targets in cancer-related pathways suggests that exposure to these fungicides may promote carcinogenic processes in these organs, raising concerns about long-term health effects [54]. Specifically, the PI3K-Akt signaling pathway plays an important role in cell survival, proliferation, and metabolism [55]. Dysregulation of this pathway may lead to neuroinflammatory responses and hepatotoxicity, which may exacerbate tissue damage. In addition, the identification of pathways associated with chemical carcinogenesis highlights the potential of these fungicides to initiate or enhance malignant transformation.