Proliferation and apoptosis of chondrocytes co-cultured with TDP43 lentivirus transfected-humanumbilical cord mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND: TDP43 may be a negative regulator of MAPK signaling pathway under hypoxic-ischemic conditions. However, its effect on JNK and p38 MAPK signaling pathways in osteoarthritis remains unclear.OBJECTIVE: To investigate the expression of chondrocyte lesion-related gene RACK1 in wild type TDP43 involved in osteoarthritis, and to analyze its stress effect. METHODS: Human umbilical cord mesenchymal stem cells were transfected by TDP43 lentivirus, and the ability to differentiate into chondrocytes in vitro was analyzed. Umbilical cord mesenchymal stem cells transfected by TDP43 lentivirus, empty vector and without transfection were co-cultured with chondrocytes for 12 days. The chondrocyte proliferation was detected at 0, 3, 6, 9 and 12 days of co-culture. The chondrocyte apoptosis rate was detected by flow cytometry at 3 days of co-culture. The expression levels of TDP43, RACK1, p38, JNK, AP-1 and cl-xl in chondrocytes were detected by qRT-PCR at 3 days of co-culture. RESULTS AND CONCLUSION: (1) After TDP43 lentivirus transfection, human umbilical cord mesenchymal stem cells could differentiate into chondrocytes. (2) The morphology of chondrocytes co-cultured with TDP43 lentivirus transfected-umbilical cord mesenchymal stem cells showed significant change, and the cells became large with abundant branches. Chondrocytes co-cultured with empty vector transfected- or non-transfected umbilical cord mesenchymal stem cells were spindle-shaped in appearance and showed adherent growth with no morphological changes. (3) After co-cultured with TDP43 lentivirus transfected-umbilical cord mesenchymal stem cells, the apoptosis of chondrocytes was promoted, and the cell proliferation was inhibited (P < 0.05). (4) The expression levels of TDP43, RACK1, p38, JNK, AP-1 and Bcl-xl in the chondrocytes co-cultured with TDP43 lentivirus transfected-umbilical cord mesenchymal stem cells were significantly higher than those in the chondrocytes co-cultured with non-transfected- and empty vector-transfected-umbilical cord mesenchymal stem cells. (5) To conclude, high expression of TDP43 in chondrocytes can activate the expression of RACK1, and further regulate chondrocyte proliferation and apoptosis.