Inhibition of ROS/NLRP3/Caspase-1 mediated pyroptosis alleviates excess molybdenum-induced apoptosis in duck renal tubular epithelial cells

Objective: Excess molybdenum (Mo) is harmful to the body, and the kidney is the vital target organ for Mo exposure. This study focused on the impacts of excess Mo on pyroptosis and the relationship between pyroptosis and apoptosis in kidney. Methods: The duck renal tubular epithelial cells were treated with (NH4)(6)Mo7O24 center dot 4H(2)O (0, 480, 720 and 960 mu M Mo), N-acetyl-L-cysteine (NAC) (100 mu M), Z-YVAD-fluommethylketone (YVAD) (10 mu M) and the combination of Mo and NAC or YVAD for 12 h. The LDH release and IL-1 beta, IL-18 contents of cell supernatant were detected by LDH and ELISA kits. The MMP and ROS level were measured using MMP and ROS kits by flow cytometry. The apoptotic rate of cell was detected by AO/EB counterstaining. Pyroptosis and apoptosis-related factors mRNA and protein levels were assayed by real-time qPCR and western blot, respectively. Results: Excessive Mo markedly increased LDH, IL-18, IL-1 beta releases and induced overproduction of ROS, pyroptosis-related factors mRNA and protein levels. NAC and YVAD dramatically decreased pyroptosis induced by Mo. Simultaneously, YVAD significantly changed apoptosis-related factors mRNA and protein levels, and reduced cell apoptotic rate. Conclusion: Excessive Mo exposure can induce pyroptosis by the ROS/NLRP3/Caspase-1 pathway in duck renal tubular epithelial cells, and restraining pyroptosis of Caspase-1 dependence might weaken excess Mo-induced apoptosis. The study provides theoretical basis for excess Mo exposure nephrotoxic researches on waterfowl and the interplay between pyroptosis and apoptosis highlights a new sight into the mechanism of Mo-induced nephrotoxicity.

Automated summary

This study found that excess molybdenum can induce pyroptosis in duck renal tubular epithelial cells through the ROS/NLRP3/Caspase-1 pathway, and inhibiting Caspase-1-dependent pyroptosis may weaken molybdenum-induced apoptosis. This provides a theoretical basis for nephrotoxic research on waterfowl exposed to excess molybdenum, and highlights a new mechanism of interaction between pyroptosis and apoptosis.