Anti-aging effects of deuterium-depleted water on Mn- induced toxicity in the Fibroblast cell model

Objectives: In recent decades, deuterium-depleted water (DDW) has been explored as a supplement for enhancing longevity. This study aimed to investigate the effects of DDW on aging-related factors, including the FOXO gene family and oxidative stress. Additionally, the study examined the impact of DDW on cellular toxicity induced by manganese, a heavy metal. Methods: The HNNFPi8 cell line was used as an experimental model and incubated in specific DDW media with deuterium concentrations of 30 ppm, 50 ppm, 75 ppm, 100 ppm, 125 ppm, and 150 ppm, along with 0.01 to 5 mM MnCl2 for up to 72 hours. Cell proliferation and the activities of catalase and superoxide dismutase (SOD) antioxidants were assessed using MTT and colorimetric methods, respectively. RT-PCR was employed to measure FOXO3A gene expression. Results: The increase in MnCl2 concentration resulted in dose-dependently reduction in the viability of the cells. However, the decrease in the cell viability in the treated groups with DDW was found to be significantly lower in concentrations of 50ppm to 125 ppm DDW. DDW at concentrations of 100 and 125 ppm could significantly upregulate the expression of FOXO3A gene in the cells treated with different concentrations of MnCl2. In addition, DDW at concentrations of 75, 100 and 125 ppm were able to increase the activities of antioxidant enzymes in the cells treated with different concentrations of MnCl 2. Conclusion: The findings suggest that DDW, particularly at concentrations of 100 and 125 ppm, is effective in mitigating the toxic effects of MnCl2.