The Effect Of Cadmium On Cell Cilia And Its Molecular Mechanism

Cadmium is a heavy metal that has toxic effects on the human body and can cause many diseases.As the antenna of cells,primary cilia can mediate various signaling pathways,such as Hedgehog(Hh)signaling pathway and Wnt signaling pathway.There are a large number of signaling receptors on the ciliary membrane,which play an important role in cell proliferation,differentiation,autophagy,apoptosis and other processes.In this experiment,in order to explore the effect of cadmium on the primary cilia and its molecular mechanism,N2 a cells and ARPE-19 cells were used as research materials.1.Immunofluorescence detection of the effect of cadmium chloride on cell ciliaAfter serum-free starvation induced ciliogenesis,cells were treated with cadmium chloride,and the cilia were stained with the ciliary marker ARL13 B.The results showed that the number of cilia was significantly reduced and the length of cilia was significantly shortened in the cadmium chloride-treated group compared with the control group.2.In order to explore the specific molecular mechanism of cadmium chloride affecting cilia,the following studies were carried out:(1)Western blot detection of ciliary transport complex IFT88 protein expressionAfter cadmium chloride treatment,the protein expression level of ciliary transport complex IFT88 was significantly decreased.(2)Western blot detection of autophagy key protein expressionWestern blot was used to detect the expression of key proteins LC3 and p62 during autophagy.The results showed that the ratio of LC3II/LC3 I increased significantly after cadmium chloride treatment,and the expression level of p62 protein was not significantly down-regulated.(3)Detection of differentially expressed proteins in cells treated with cadmium chlorideCellular proteins were extracted by DOC method for mass spectrometry analysis.The results showed that the expression levels of heme oxygenase 1(HO-1)and GADD45βinvolved in the regulation of autophagy and apoptosis were significantly increased after cadmium chloride treatment.(4)Detection of changes in the expression of transcription factor Nrf2HO-1 is a classic target gene of Nrf2,so the expression of Nrf2 involved in cilia regulation was detected.The expression level of Nrf2 protein was detected by Western blot.Compared with the control group,cadmium chloride treatment significantly increased the expression level of Nrf2 protein.(5)Detection of the localization of transcription factor Nrf2 in cellsThe localization changes of Nrf2 in cells after cadmium chloride treatment were detected by immunofluorescence.The results showed that the transcription factor Nrf2 migrated to the nucleus after cadmium chloride treatment.Taken together,cadmium chloride treatment resulted in shorter cell cilia.Cadmium chloride mediates ciliary damage by blocking autophagy and activating the transcription factor Nrf2.This study can provide a theoretical reference for the study of the toxicological mechanism of cadmium and serve as a scientific basis for the health risk assessment of cadmium toxicity.