Evaluation of treatment for acute hexavalent chromium poisoning in human renal proximal tubular epithelial cells with 2,3-dimercapto-1-propanesulfonic acid (DMPS).

OBJECTIVES: Chelating agents have been utilized in clinical settings to counteract various heavy metal poisonings, although there are currently no established medical guidelines supporting the use of the chelating agent 2,3-dimercapto-1-propanesulfonic acid (DMPS) for treating acute hexavalent chromium (Cr(VI)) poisoning. METHODS: Since systemic acute Cr(VI) poisoning has been associated with nephrotoxicity in clinical cases, this study utilized the immortalized human renal epithelial cell line HK-2 and primary proximal tubular epithelial cells (RPTEC) as in vitro models to explore potential treatments. RESULTS: In the HK-2 cell model, cell viability dropped below 50% after exposure to 10 μmol/L Cr(VI) for 32 hours. Both simultaneous administration of 10 μmol/L Cr(VI) with 100 or 300 μg/mL DMPS and delayed treatment with DMPS after two hours effectively reduced Cr(VI)-induced cell death. Furthermore, in the RPTEC cell model, DMPS treatments ranging from 300 to 1000 μg/mL demonstrated significant protective effects on cell viability against Cr(VI) toxicity, mirroring the results observed in the HK-2 model. In contrast, meso-2,3-dimercaptosuccinic acid, another chelating agent, did not exhibit protective effects on HK-2 cells. CONCLUSIONS: These findings support DMPS as a promising antidote for acute Cr(VI) poisoning in kidney cells and provide valuable insights for potential clinical applications.