Fig 2: Effects of miR-140-5p on chondrocyte growth and differentiation marker protein expression and localization. Positive signals for protein expression are shown by red and green fluorescence, whereas blue represents the nucleus. The scale bars represent a length of 200 µm. The fluorescence signal of the HDAC4 protein was stronger in the miR-140-5p inhibitor group than in the control group. In the inhibitor group, fluorescent signals from proteins such as MEF2C, Runx2, VEGFA, Col-II, and Col-X were scarcely discernible. However, in the miR-140-5p mimics group, these proteins’ fluorescence signals were clearly evident, and suggesting increased expression.

Fig 3: (A): Expression of chondrocyte growth and differentiation-related marker proteins after treatment with ITSA-1 and LMK-235 for 24h, using GAPDH as an internal reference protein. The densitometry of protein bands on the Fusion Solo S instrument. (B): A fluorescence experiment was used to examine the effects of ITSA-1 and LMK-235 on the expression and localization of chondrocyte growth and differentiation marker proteins. Red and green fluorescence were utilized as positive signals in this experiment to indicate protein expression, whereas blue fluorescence was used to observe the cell nucleus. A fluorescence microscope was used to view and record the fluorescence signals, and pictures were collected using a scale bar of 200 µm to give a reference for size measurements. The assay revealed a weak fluorescence signal of HDAC4 in the chondrocytes of the LMK-235 group. However, the fluorescence signals of Col-X, MEF2C, COMP, and Col-II were remarkably high, indicating their increased expression in response to treatment. The red text refers to a distinct band corresponding to targeted molecular weight (MW). “*” shows the level of significance among groups. *** p < 0.001.