Ipconazole Disrupts Mitochondrial Homeostasis and Alters GABAergic Neuronal Development in Zebrafish

Abstract

Ipconazole, a demethylation inhibitor of fungal ergosterol biosynthesis, is widely used in modern agriculture for foliar and seed treatment, and is authorized for use in livestock feed. Waste from ipconazole treatment enters rivers and groundwater through disposal and rain, posing potential toxicity to humans and other organisms. Its metabolites remain stable under standard hydrolysis conditions; however, their neurodevelopmental toxicity is unknown. We investigated the potential neurodevelopmental toxicity of ipconazole pesticides in zebrafish (Danio rerio). Our behavioral monitoring demonstrated that the locomotive activity of ipconazole-exposed zebrafish larvae was reduced during early development, even when morphological abnormalities were undetected. Molecular profiling demonstrated that the mitochondrial-specific antioxidants, superoxide dismutases 1 and 2, and the genes essential for mitochondrial genome maintenance and functions were specifically reduced in ipconazole-treated (0.02 μg/mL) embryos, suggesting underlying ipconazole-driven oxidative stress. Consistently, ipconazole treatment substantially reduced hsp70 expression and increased ERK1/2 phosphorylation in a dose-dependent manner. Interrupted gad1b expression confirmed that GABAergic inhibitory neurons were dysregulated at 0.02 μg/mL ipconazole, whereas glutamatergic excitatory and dopaminergic neurons remained unaffected, resulting in an uncoordinated neural network. Additionally, ipconazole-treated (2 μg/mL) embryos exhibited caspase-independent cell death. This suggests that ipconazole has the potential to alter neurodevelopment by dysregulating mitochondrial homeostasis.

Application of Zebrafish in Mitochondrial Dysfunction

“…Since then, several studies have evaluated mitochondrial dysfunction, mainly by analyzing mitochondrial oxygen consumption for mitochondrial toxicity, such as the work of Bourdineaud et al [115], evaluating environmental pollutants; the work of Geffroy et al [116] and Ladhar et al [117], evaluating nanoparticles, already entering the area of nanotoxicology; the work of Bestman et al [118], also evaluating an organic compound for the manufacture of pesticides; and Cowie et al stating mitochondrial dysfunction of zebrafish caused by the pesticide Dieldrina [119]. Other studies have also evaluated pesticides using mitochondrial dysfunction as a method of toxicological analysis [49,53,54,[120][121][122][123][124][125][126][127][128][129][130][131][132][133].…”

Differential Neuroprotective Effects of N-Acetylcysteine against Dithianon Toxicity in Glutamatergic, Dopaminergic, and GABAergic Neurons: Assessment Using Zebrafish

“…Zebrafish (Danio rerio) is a useful vertebrate model in studies on hazard identification, particularly in toxicological research of environmental chemicals [24]. Tiny, transparent embryos of zebrafish can be obtained in large numbers, allowing the visualization of tissue development in live animals [25][26][27].…”

Ipconazole Induces Oxidative Stress, Cell Death, and Proinflammation in SH-SY5Y Cells

“…In [ 12 ], the authors report only the presence of ipconazole residues in grains that could be factors in altering consumer health. In another study, zebrafish embryos treated with ipconazole at low doses exhibited cell death independent of the caspase enzyme, suggesting that ipconazole has the potential to alter neurodevelopment through dysregulation of mitochondrial homeostasis [ 13 ].…”