Effects of Cr(VI)-induced calcium-sensing receptor activation on DF-1 cell pyroptosis

This study aims to investigate the effects of Cr(VI)-induced calcium-sensing receptor (CaSR) activation on DF-1 cell pyroptosis. Previous studies show that Cr(VI) could accumulate in the body of chickens and change Ca levels. Hence, a Ca-related pathway may be an important mechanism participating in some pathological processes. Pyroptosis level, which is meditated by CaSR, increases under Cr(VI) accumulation. In the present study, pyroptosis was determined by flow cytometry to detect SYTOX blue and caspase-1 staining followed by morphological observation. Interleukin (IL)-1β and IL-18 levels were detected by ELISA, while CaSR protein and [Ca²⁺]_i contents were detected by Western blot and fluorescence microplate spectrophotometry, respectively. The results showed that Cr(VI) causes DF-1 cell pyroptosis in a time- and dose-dependent manner and that this effect is caspase-1 dependent. Further experiments indicated that pyroptosis could be induced by Cr(VI) and is accompanied by up-regulated [Ca²⁺]_i content. CaSR inhibition led to decreases in pyroptosis level. Some mechanisms may be involved in Cr(VI)-triggered CaSR activation and enhance DF-1 cell pyroptosis. Taken together, the results of this study support future investigations on Cr(VI)-induced pyroptosis in DF-1 cells.