Fig. 4
SPI1 inhibits the mechanical stress-induced senescence of chondrocytes. a CCK-8 was used to assess the proliferative activity of chondrocytes in model groups with SPI1 overexpression or inhibition. b β-Galactosidase staining was used to assess the chondrocytes in model groups with SPI1 overexpression or inhibition (n = 6 per group). Scale bars: 50 μm. c IL-6, IL-8, and TNF-α levels in the culture supernatant of chondrocytes with SPI1 overexpression or inhibition in model groups were measured by ELISA. d Mitochondrial respiratory chain complexes I-IV were assessed in chondrocytes with SPI1 overexpression or inhibition in model groups. e, f Mitochondrial membrane potential in chondrocytes with SPI1 overexpression or inhibition in model groups was measured by flow cytometry and observed by microscopy. Scale bars: 50 μm. g The morphology of mitochondria was observed by TEM in chondrocytes with SPI1 overexpression or inhibition in model groups. Scale bars: 2 μm and 500 nm. The cell sample size is n = 4. Experiments were independently repeated three times. The data were expressed as mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.000 1 versus the Control group. t-test
