TY - JOUR AB - Osteoarthritis (OA), also known as degenerative joint disease or degenerative arthritis, is characterized by chondrocyte apoptosis. The aim of the present study was to investigate the effects of collagen triple helix repeat containing 1 (CTHRC1) and the c‑Jun N‑terminal kinase (JNK) 1/2 inhibitor SP600125 on rat chondrocytes cultured in vitro with interleukin (IL)‑1β. Chondrocytes were treated with different doses of IL‑1β and cell viability and CTHRC1 expression were assessed using Cell Counting Kit‑8 and western blot assays, respectively. In separate experiments, chondrocytes were treated with CTHRC1‑expressing constructs (pLVX‑Puro‑CTHRC1) and/or SP600125, or IL‑1β with either CTHRC1 short hairpin (sh)RNA constructs (shNRA‑CTHRC1) or SP600125. The expression of CTHRC1, B‑cell lymphoma (Bcl)‑2, Bcl‑2‑associated X protein (Bax), cleaved caspase‑3, poly ADP ribose polymerase (PARP)‑1 and matrix metalloproteinase (MMP)‑13 was measured using reverse transcription‑quantitative polymerase chain reaction and western blotting assays. A Cell Counting Kit‑8 assay was performed to examine cell viability. Annexin V/propidium iodide staining and flow cytometry assays were used to detect chondrocyte apoptosis. The expression of JNK1/2 and phosphorylated JNK1/2 was measured using western blotting. CTHRC1 was highly expressed in patients with OA compared with normal controls. IL‑1β treatment (5, 10 and 20 ng/ml) increased the protein expression of CTHRC1 in a dose‑dependent manner and decreased the viability of chondrocytes in a time‑dependent manner. pLVX‑Puro‑CTHRC1 mimics the effect of IL‑1β on chondrocyte apoptosis and JNK1/2 activity, and this is reversed by SP600125 treatment. However, transfection with shRNA‑CTHRC1 or treatment with SP600125 inhibited IL‑1β‑induced cell apoptosis and JNK1/2 activation. These results indicate that CTHRC1 downregulation may protect chondrocytes from IL‑1β‑induced apoptosis by inactivating the JNK1/2 pathway. AD - Department of Orthopedics, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, P.R. China AU - Zhang,Qi AU - Yin,Zong‑Sheng AU - Zhang,Fu‑Wen AU - Cao,Kun AU - Sun,He‑Yan DA - 2018/04/01 DO - 10.3892/ijmm.2018.3403 EP - 2278 IS - 4 JO - Int J Mol Med KW - chondrocyte interleukin‑1β collagen triple helix repeat containing 1 apoptosis c‑Jun N‑terminal kinase 1/2 PY - 2018 SN - 1107-3756 1791-244X SP - 2270 ST - CTHRC1 mediates IL‑1β‑induced apoptosis in chondrocytes via JNK1/2 signaling T2 - International Journal of Molecular Medicine TI - CTHRC1 mediates IL‑1β‑induced apoptosis in chondrocytes via JNK1/2 signaling UR - https://doi.org/10.3892/ijmm.2018.3403 VL - 41 ER -