TY - JOUR AB - A single injection of low‑dose human umbilical cord‑derived mesenchymal stem cells (UC‑MSCs) has been previously demonstrated to relieve synovitis and bone erosion in animal models of arthritis, but whether frequent injections of high‑dose UC‑MSCs relieve arthritis and inhibit loss of muscle mass has remained elusive. In the present study, DBA/1 mice were randomly divided into three groups: Normal (wild‑type mice; n=11), collagen‑induced arthritis (CIA; n=12) and CIA treated with UC‑MSCs (n=11; 5x106 UC‑MSCs per week for 3 weeks). Arthritis and skeletal muscle cachexia were evaluated until the end of the experiment on day 84. It was indicated that both the CIA and UC‑MSC groups had lower body weights compared with the normal mice. Clinical arthritis scores, hind ankle diameters, synovitis and bone erosion progressively increased and were similar between the CIA and UC‑MSC groups. Although there was no difference in food intake among the three groups, the normalized food intake of normal group was significantly higher than CIA group and UC‑MSC group from day 42 onwards; there was no significance on day 77 but this could be neglected. Furthermore, gastrocnemius muscle weight in the UC‑MSC group was significantly reduced compared with that in the CIA and normal groups. The UC‑MSC group had higher levels of proinflammatory cytokines, such as TNF‑α, IL‑6 and IL‑1β than those in the CIA group. However, the other cytokines assessed and the fibrosis indices in the CIA and UC‑MSC groups were not different from those in the control group and there was no inflammatory cell infiltration. Thus, frequent injections of high‑dose UC‑MSCs slightly aggravated synovitis and muscle cachexia in the murine CIA model and should therefore be avoided in the treatment of arthritis. AD - Department of Rheumatology and Clinical Immunology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, P.R. China Department of Cardiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, P.R. China Henan Key Laboratory of Stem Cell Differentiation and Modification, Stem Cell Research Center, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, Henan 450003, P.R. China Neuroscience Initiative, Advanced Science Research Center at the Graduate Center, City University of New York, New York, NY 10031, USA Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing 100034, P.R. China AU - An,Lemei AU - Chu,Tianshu AU - Wang,Liujun AU - An,Songtao AU - Li,Yalong AU - Hao,Hongbo AU - Zhang,Zhuoli AU - Yue,Han DA - 2021/11/01 DO - 10.3892/etm.2021.10707 IS - 5 JO - Exp Ther Med KW - rheumatoid arthritis muscle cachexia inflammation fibrosis human umbilical cord mesenchymal stem cells PY - 2021 SN - 1792-0981 1792-1015 SP - 1272 ST - Frequent injections of high‑dose human umbilical cord mesenchymal stem cells slightly aggravate arthritis and skeletal muscle cachexia in collagen‑induced arthritic mice T2 - Experimental and Therapeutic Medicine TI - Frequent injections of high‑dose human umbilical cord mesenchymal stem cells slightly aggravate arthritis and skeletal muscle cachexia in collagen‑induced arthritic mice UR - https://doi.org/10.3892/etm.2021.10707 VL - 22 ER -