The effect of Shh signaling pathway changes on autophagy in mouse embryonic palatal mesenchymal cells

Abstract:

Objective To explore the changes of autophagy of mouse embryonic palatal mesenchymal cells after the changes of Shh signaling pathway in mouse embryonic palatal mesenchymal cells treated with dexamethasone（DEX） and smoothened agonist（SAG）.Methods C57BL/6J mouse palatal mesenchymal cells were cultured in vitro for 14.5 days and divided into 4 groups according to the interventions：blank control group，DEX group，DEX + SAG group and SAG alone group. The number of autophagosomes or autophagy lysosomes in each group was observed by transmission electron microscope，and the expression of Shh，Ptch1，Smo，Gli3A/R，Cyclin D1 and autophagy markers LC3 Ⅱ/Ⅰ，P62 and Beclin-1 were detected by Western blot.Results The results of electron microscopy showed that there was no significant difference in the number of autophagosomes/autophagy lysosomes between control group and DEX group， but a large number of autophagosomes/autophagy lysosomes could be observed after SAG intervention. The results of Western blot showed that compared with the control group，the expression of P62， Ptch1，Smo，Gli3A/R and Cyclin D1 in DEX group decreased significantly（P<0.05），while the expression of LC3Ⅱ/Ⅰ and Beclin1 had no significant change in DEX + SAG group and SAG group（P>0.05）. The expression of Ptch1，Smo，Gli3A/R and Cyclin D1 in DEX+SAG group and SAG group was significantly higher than that in DEX group（P<0.05），but there was no significant difference in Shh expression（P>0.05）. The Beclin1 expression increased significantly（P<0.05） and P62 expression significantly decreased（P<0.05）. Compared with SAG group，the expression of Smo，Gli3A/R，Ptch1 and Cyclin D1 in DEX+SAG group was significantly lowered down（P<0.05），while the expression of Shh was not significantly different（P>0.05）. And LC3Ⅱ/Ⅰ，Beclin1 and P62 expression were significantly increased（P<0.05）.Conclusion DEX can inhibit the Shh signaling pathway of mouse embryonic palatal mesenchymal cells and activate Shh signaling pathway. It can induce autophagy of mouse embryonic palatal mesenchymal cells and reactivate the Shh pathway，and autophagy turns more obvious.