Department of Orthopedic Surgery, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea , Seoul, Korea.
Department of Orthopedic Research, Medical Research Institute, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea , Seoul, Korea.
Biotech Histochem. 2020 Oct;95(7):490-498. doi: 10.1080/10520295.2020.1721560. Epub 2020 Feb 10.
We investigated the effect of prolonged rhBMP-2 treatment on telomerase activity, replicative capacity and senescence of nucleus pulposus cells (NPCs) during long term culture. We obtained intervertebral disc (IVD) tissues with grade III degeneration from four patients. NPCs were isolated and passaged serially in three groups: control group, low-dose rhBMP-2 group and high-dose rhBMP-2 group until the cells reached the end of their replicative lifespan. Cumulative population doubling level (CPDL), telomerase activity and senescence markers, senescence-associated β-galactosidase (SA-β-gal), p53, p21, and p16, were assessed. The replicative capacity of NPCs in the high-dose rhBMP-2 group was decreased significantly compared to the control and low-dose rhBMP-2 groups. Mean telomerase activity was significantly greater in the high-dose rhBMP-2 group compared to the control and low-dose rhBMP-2 groups. The percentage of SA-β-gal-positive NPCs increased more rapidly in the high-dose rhBMP-2 group with passaging compared to the control and low-dose rhBMP-2 groups. The expression of p53, p21, and p16 in both low and high dose rhBMP-2 groups increased in all passages compared to the control group. We found that prolonged high-dose rhBMP-2 treatment increased telomerase activity of human NPCs, but decreased replicative capacity and lifespan in long term culture. We also found that excessive growth stimulation by prolonged high-dose rhBMP-2 treatment can promote NPCs senescence and result in growth arrest.
我们研究了在长期培养过程中，延长 rhBMP-2 处理对纤维环细胞（NPC）端粒酶活性、复制能力和衰老的影响。我们从四位患者中获得了 III 级退变的椎间盘组织。将 NPC 分离并在三组中连续传代：对照组、低剂量 rhBMP-2 组和高剂量 rhBMP-2 组，直到细胞达到复制寿命的终点。评估累积倍增水平（CPDL）、端粒酶活性和衰老标志物，衰老相关β-半乳糖苷酶（SA-β-gal）、p53、p21 和 p16。与对照组和低剂量 rhBMP-2 组相比，高剂量 rhBMP-2 组 NPC 的复制能力明显下降。高剂量 rhBMP-2 组的平均端粒酶活性明显高于对照组和低剂量 rhBMP-2 组。与对照组和低剂量 rhBMP-2 组相比，高剂量 rhBMP-2 组 NPC 中 SA-β-gal 阳性细胞的比例随传代增加得更快。与对照组相比，低剂量和高剂量 rhBMP-2 组的 p53、p21 和 p16 在所有传代中表达均增加。我们发现，延长高剂量 rhBMP-2 处理增加了人 NPC 的端粒酶活性，但降低了长期培养中的复制能力和寿命。我们还发现，延长高剂量 rhBMP-2 处理的过度生长刺激可促进 NPC 衰老并导致生长停滞。
