This study aims to investigate the mechanism by which dexamethasone regulates autophagy in mouse embryonic palatal mesenchymal cells, thereby providing a theoretical basis for the prevention of cleft palate. In vitro, the 14.5-day palatine mesenchymal cells of C57BL/6J mouse embryos were extracted and cultured in vitro and the 14.5-day palatine mesenchymal cells were randomly divided into control (CON) group and dexamethasone (DEX) groups according to the intervention conditions. The number of autophagosomes or autophagolysosomes in each group was observed by transmission electron microscopy. Western blot was used to detect the protein expression changes of PI3K, p-PI3K, AKT, p-AKT, mTOR, LKB1, p-LKB1, p38MAPK, p-p38MAPK and autophagy markers LC3Ⅱ/I, P62 and Beclin 1. Transmission electron microscopy results showed that the number of autophagosomes/autophagolysosomes was significantly reduced in the DEX group compared with the CON group (P<0.05). Western blot results showed that compared with the CON group, Beclin 1 was reduced in DEX group, p62 was increased (P<0.05), and there was no significant change in LC3Ⅱ/I expression (P>0.05); PI3K/AKT/mTOR signaling pathway was significantly inhibited in DEX group (PI3K, p-PI3K, AKT, p-AKT, mTOR expression was decreased, P<0.05), and LKB1 signaling pathway and p38MAPK signaling pathway were significantly activated ((LKB1, p-LKB1, p38MAPK, p-p38MAPK, p-p38MAPK, P<0.05). DEX may be activated by inhibiting the PI3K/AKT/mTOR pathway, and p38MAPK pathway inhibits autophagy of mouse embryonic palatal mesenchymal cells.

Bing Xu, Zhe Wang, Juerong Chen, Zhijiang Zou, Kehan Chen, Guo'ao Zhou, Wei He. Regulation of Autophagy in Mouse Embryonic Palatal Mesenchymal Cells by Dexamethasone through the PI3K/AKT Pathway. International Journal of Frontiers in Medicine (2025), Vol. 7, Issue 4: 50-58. https://doi.org/10.25236/IJFM.2025.070408.

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