Systemic liver metabolic disturbances induced by chronic exposure to a mixture of environmentally prevalent heavy metals: A risk insight from murine model

The liver is a key metabolic organ that is especially vulnerable to damage from heavy metal exposure due to its role in detoxification and metabolic regulation. Hepatic metabolites serve as sensitive biomarkers that reflect systemic responses to xenobiotics, including environmental metals. This study aimed to assess liver metabolic alterations following real-time exposure to a complex mixture of seven metals and one metalloid, commonly found as environmental contaminants. Male and female Swiss albino mice were randomly assigned to 12 experimental groups and exposed to graded doses (1X, 5X, 10X, 50X, and 100X) of the metal mixture via drinking water for eight weeks. Liver tissues from treated and control animals were analyzed using gas chromatography-mass spectrometry (GC-MS) to identify changes in endogenous metabolites. The orthogonal partial least squares-discriminant analysis (OPLS-DA) revealed clear separations between control and metal-exposed groups, indicating dose- and sex-specific metabolic disruptions. Regression -based dose-response analysis with FDR correction (FDR < 0.05) revealed significant perturbation for 31 metabolites with increasing dose of multi metal mixture. Statistically significant alterations (p < 0.05, VIP > 1.0) were observed in metabolites associated with amino acid metabolism, fatty acid biosynthesis, glyoxylate and dicarboxylate metabolism, energy production, and sulfur metabolism. Collectively, these findings highlight the detrimental impact of chronic exposure to environmental metal mixtures on liver metabolic homeostasis and provide critical insights into sex-specific toxicological mechanisms. • GC-MS metabolomics revealed dose-dependent hepatic shifts under multi-metal stress. • Amino acid, lipid, and sulfur pathways were major targets of metal-induced disruption. • Glutathione depletion reflected impaired antioxidant defense in metal exposed mice. • Disturbed TCA cycle indicated mitochondrial dysfunction under metal burden. • Female mice exhibited broader and more severe metabolic perturbations than males. • Study provides novel metabolomic evidence of chronic multi-metal hepatotoxicity.