2025, Vol. 29 ›› Issue (8): 1541-1547

Effect of Complanatoside A on the apoptosis of articular chondrocytes

Yin Lu1, Jiang Chuanfeng1, Chen Junjie1, Yi Ming1, Wang Zihe1, Shi Houyin2, Wang Guoyou2, Shen Huarui2   

Abstract: BACKGROUND: Chondrocyte apoptosis is an important factor in the development of osteoarthritis, and Complanatoside A has a flavonoid effect, which can inhibit apoptosis of various cells, but its effect on chondrocyte apoptosis and the mechanism of action are not clear.
OBJECTIVE: To investigate the intrinsic association and mechanism of Complanatoside A in chondrocyte apoptosis based on the Wnt/β-catenin signaling pathway.
METHODS: (1) The cartilage tissues of the femur and tibia transected during knee arthroplasty were collected, and chondrocytes were isolated, cultured in vitro, and identified. (2) Cell counting kit-8 was used to detect the optimal intervention concentration of Complanatoside A in the concentration range of 0-
160 μmol/L. (3) Chondrocytes were divided into blank group, sodium nitroprusside (1.5 mmol/L)-induced group, and sodium nitroprusside (1.5 mmol/L)+
Complanatoside A (5 μmol/L) group. The viability and apoptosis rate of the cells in each group were detected by cell counting kit-8 and flow cytometry. The expression of type II collagen and SOX9 was detected by immunofluorescence staining. The expression of apoptosis-related proteins and Wnt/β-catenin pathway proteins was detected by western blot assay.
RESULTS AND CONCLUSION: The cells extracted in vitro were cultured and stained, and were clearly identified as chondrocytes. Complanatoside A had no obvious cytotoxicity to chondrocytes in the concentration range of 0-80 μmol/L, and significantly improved the chondrocyte viability in the concentration range of 2.5-10 μmol/L, especially when the concentration was 5 μmol/L. The apoptotic rate of chondrocytes was higher in the sodium nitroprusside-induced group than the blank control group, while the apoptotic rate was lower in the sodium nitroprusside+Complanatoside A group than the sodium nitroprusside-induced group. The fluorescence intensity of type II collagen and SOX9 in chondrocytes was weaker in the sodium nitroprusside-induced group than the blank control group, while the fluorescence intensity of type II collagen and SOX9 in the sodium nitroprusside+Complanatoside A group was higher than that of the sodium nitroprusside-induced group. In the sodium nitroprusside-induced group, the protein expression of Bax, Caspase-3, matrix metalloproteinase 13, Wnt3a, Wnt5a and β-catenin was higher than that of the blank control group, while the protein expression of Bcl-2 was lower than that of the blank control group. In the sodium nitroprusside+Complanatoside A group, except for the protein expression of Bcl-2 which was higher than that of the sodium nitroprusside-induced group, the expression of the other aforementioned proteins was lower than that of the sodium nitroprusside-induced group. To conclude, Complanatoside A has a certain inhibitory effect on chondrocyte apoptosis, which could regulate apoptosis-related proteins and promote the expression of chondrocyte regulatory factors, and presumably might play a role through inhibiting the Wnt/β-catenin signaling pathway.
Key words: osteoarthritis, chondrocyte, Complanatoside A, apoptosis, Wnt/β-catenin signaling pathway