Rapamycin-Induced Autophagy Promotes the Chondrogenic Differentiation of Synovium-Derived Mesenchymal Stem Cells in the Temporomandibular Joint in Response to IL-1β

Figure 3

IL-1β inhibits autophagy in SMSCs by activating mTOR. (a) Transmission electron microscopy images showing autophagosomes in SMSCs after chondrogenic induction for 24 h (arrows, scale ). (b) Expression of the autophagy-related proteins mTOR and LC3 in SMSCs treated with IL-1β ( indicates compared with the control group). (c) SMSCs were seeded on glass coverslips for 24 h in the chondrogenic induction culture medium, chondrogenic induction culture medium supplemented with 100 nM rapamycin, chondrogenic induction culture medium supplemented with 10 ng/mL IL-1β, or with a 1-h preincubation with 100 nM rapamycin prior to the addition of 10 ng/mL IL-1β in the chondrogenic induction culture medium, and LC3-positive punctures were observed in an immunofluorescence assay (scale ).

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