Researchers have identified how 6-PPD quinone (6-PPDQ), an environmental contaminant derived from tire antioxidants, significantly disrupts the citric acid cycle in the nematode Caenorhabditis elegans at concentrations relevant to environmental exposure. Published in the journal Environmental Chemistry and Ecotoxicology, the study demonstrates that 6-PPDQ reduces key metabolites and suppresses gene expressions essential for this central metabolic pathway, pointing to broader implications for environmental and human health. The citric acid cycle is fundamental for cellular metabolism, linking the breakdown of carbohydrates, fats, and proteins to energy production.
The research found that exposure to 6-PPDQ at concentrations between 0.1 and 10 micrograms per liter led to a marked decrease in cycle intermediates and the expression of genes critical for the cycle's function. These genes include those encoding enzymes like citrate synthase and isocitrate dehydrogenase. This disruption was accompanied by reduced levels of acetyl CoA and pyruvate, further impairing mitochondrial function and energy production in the nematodes. The findings underscore the contaminant's ability to interfere with a core biological process at very low, environmentally realistic levels.
Interestingly, the study also explored the potential of sodium pyruvate to mitigate 6-PPDQ's toxic effects, suggesting a possible avenue for addressing contamination impacts. The research emphasizes the urgent need for further investigation into 6-PPDQ's environmental presence and its effects on metabolic pathways across different species. For more detailed information on the study's methodology and data, refer to the original publication available at https://www.sciencedirect.com/science/article/pii/S2590162123001235. The work underscores the potential risks this tire-derived contaminant poses to ecosystems and, by extension, human health, given the ubiquity of tire wear particles in the environment.
