2022, Vol. 26 ›› Issue (26): 4160-4165

Effects of suppressor of cytokine signaling 3 on osteogenic activity in the cartilage of adolescent idiopathic scoliosis

Sun Jinpeng, Liu Jun, Bai Yunfeng, Hua Feng, Wang Haoran, Zheng Hongrui, Wu Tao   

Abstract: BACKGROUND: It has been reported that the abnormal expression of leptin and suppressor of cytokine signaling 3 (SOCS3) plays an important role in the pathogenesis of adolescent idiopathic scoliosis.
OBJECTIVE: To investigate whether SOCS3 regulates the osteogenic activity of chondrocytes through the leptin signaling pathway.
METHODS: Human spinous chondrocytes were stimulated with 0 (blank control group) and 100 µg/L leptin for 24 hours, and immunohistochemical staining was used to detect the expression of type II collagen. The human spinous chondrocytes were cultured in nine groups: a blank control group, a pcDNA3.1-NC transfected group, a pcDNA3.1-SOCS3 transfected group, a siRNA-NC transfected group, a siRNA-SOCS3 transfected group, a leptin+transfected pcDNA3.1-NC group, a leptin+transfected pcDNA3.1-SOCS3 group, a leptin+transfected siRNA-NC group, and a leptin+transfected siRNA-SOCS3 group. After being cultured in an incubator for 24 hours, real-time fluorescent quantitative PCR was used to detect the mRNA expression of SOCS3, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to detect the cell inhibition rate.
RESULTS AND CONCLUSION: Results of immunohistochemical staining showed that the expression of type II collagen in chondrocytes s was higher in leptin-stimulated group than the blank control group. Results of real-time fluorescence quantitative PCR showed that transfection of pcDNA3.1-SOCS3 could significantly increase the mRNA expression of SOCS3 in chondrocytes, and transfection of siRNA-SOCS3 could significantly reduce the mRNA expression of SOCS3 in chondrocytes. In contrast, transfection of pcDNA3.1-NC and siRNA-NC had no effect on the mRNA expression of SOCS3 in chondrocytes. Leptin pre-stimulation could increase the mRNA expression of SOCS3 in chondrocytes transfected with pcDNA3.1-SOCS3 and siRNA-SOCS3, but it had no effect on the mRNA expression of SOCS3 in chondrocytes transfected with pcDNA3.1-NC and siRNA-NC. Results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that transfection of pcDNA3.1-SOCS3 could inhibit the osteogenic activity of chondrocytes, and transfection of siRNA-SOCS3 could enhance the osteogenic activity of chondrocytes. And leptin pre-stimulation could increase the osteogenic activity of chondrocytes transfected with pcDNA3.1-NC, pcDNA3.1-SOCS3, siRNA-NC, and siRNA-SOCS3. These findings indicate that leptin stimulation can increase the osteogenic activity of chondrocytes, and upregulating the expression of SOCS3 can inhibit the osteogenic activity of chondrocytes through leptin resistance.
Key words: leptin, suppressor of cytokine signaling 3, chondrocyte, adolescent, scoliosis, plasmid transfection