Effect of Nano Red Elemental Selenium on GPx Activity of Broiler Chick Kidney Cells in vitro

A new selenium source, Nano red elemental selenium (Nano-Se) was used to study the effect on the GPx activity of broiler chick kidney cells (BCKC) in vitro, Sodium selenite (Na_ 2 SeO_ 3 ) and seleno-1-methionine (Se-Met) were used as the controls. The results showed that the effects of three kinds of Se forms on the GPx activity of BCKC were accordant(p>0.05) compared with each other at 0.01,0.05 and 0.10 μmol/L Se concentrations treatments. In the range of 0.00-0.10 μmol/L Se concentrations, the GPx activity increased with elevation of Se concentrations in medium. For the three kinds of Se forms, the GPx activity reached the climax at 0.10 μmol/L Se concentration. At 0.20 and 0.30 μmol/L Se concentrations, the influnces of three kinds of Se forms were not accordant with one another. For Nano-Se, the GPx activity at 0.20 and 0.30 μmol/L Se concentrations remained the same as that at 0.10 μmol/L Se concentration treatment. For Se-Met, the GPx activity at 0.20 μmol/L Se concentration treatment remained the same with 0.10 μmol/L treatment; the GPx activity at 0.30 μmol/L Se concentration treatment was declined significantly(p<0.05) compared with 0.10 or 0.20 μmol/L treatment. For Na_ 2 SeO_ 3 , the GPx activity falled gradually with Se concentration increasing from 0.10 μmol/L to 0.30 μmol/L, and at 0.30 μmol/L Se concentration treatment, the GPx activity was less than the original of BCKC. The results implicated, on the GPx activity of BCKC in vitro, the ranking of width range of the most suitable Se concentration for nutrition curve of the three Se formes is Nano-Se>Se-Met>Na_ 2 SeO_ 3 .

Visualization of the process:selenocysteine activates GPX4 in ferroptosis based on a nano-fluorescent probe

Developing accurate methods for visualizing the expressions of proteins during the life process is a hotspot in the biochemical research field.Glutathione peroxidase 4(GPX4),one type of selenoproteins,was previously identified as a significant ferroptosis-regulated protein.Therefore,a novel approach was established to visualize the activation process of selenocysteine(Sec)toward GPX4 via an Au–Se bonded fluorescent nanoprobe and assisted by western blot analysis.The Au–Se nanoprobe was constructed by selenol-modified peptides for monitoring the concentration changes of Sec.The fluorescence intensity of Sec in confocal fluorescence imaging positively correlates with GPX4's activation level,proved by western blot analysis in living cells.This study provides an intuitional and visual strategy for predicting the functional expression of GPX4 during the ferroptosis process and offers new directions for the future investigation of proteins'functional expressions.