Tang Yan-Long, Zhou Yue, Wang Ya-Ping, He Ying-Hong, Ding Ji-Chao, Li Yuan, Wang Cui-Li
Department of Histology and Embryology, Key Laboratory of Cell Biology, Dali University, Dali, Yunnan 671000, P.R. China.
Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology, Chongqing Medical University, Chongqing 400016, P.R. China.
Exp Ther Med. 2020 Aug;20(2):1245-1252. doi: 10.3892/etm.2020.8810. Epub 2020 May 28.
Aging is characterized by a progressive deterioration in metabolic functions. The present study aimed to investigate the antagonistic effects of ginsenoside Rg1 (Rg1) on the γ-ray irradiation-induced aging of mixed hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs). C57BL/6 mice were divided into a control group, a γ-ray irradiation group that served as an aging mouse model, and an Rg1 group. The Rg1 group was treated with Rg1 at dosage of 20 mg/kg/day for 7 days prior to γ-ray irradiation. The aging mouse model was established by exposing the mice to 6.5-Gy γ-ray total-body irradiation. Stem cell antigen 1 positive (Sca-1) HSC/HPCs isolated from the mice were examined using a senescence-associated β-galactosidase (SA-β-Gal) staining assay. The cell cycle of the HSC/HPCs was examined using flow cytometry. A mixed hematopoietic progenitor cell colony-forming unit (CFU-mix) assay was also conducted. The mRNA and protein expression levels of sirtuin 1 (SIRT1), SIRT3, forkhead box O3 (FOXO3) and superoxide dismutase (SOD2) were evaluated using western blot and reverse transcription-quantitative PCR assays. The results indicated that Rg1 treatment significantly increased white blood cell, red blood cell and platelet counts in peripheral blood compared with those in the γ-ray irradiation group (P<0.05). However, Rg1 significantly attenuated the senescence of Sca-1 HSC/HPCs in the γ-ray irradiation aging mice model. The proportion of SA-β-Gal stained HSC/HPCs was significantly decreased and CFU-Mix counts were significantly increased in the Rg1 group compared with the γ-ray irradiation group (P<0.05). Rg1 significantly increased the mRNA and protein levels of SIRT1, SIRT3, FOXO3 and SOD2 in the Sca-1 HSC/HPCs compared with those in the γ-ray irradiation group (P<0.05). The percentage of Sca-1 HSC/HPCs arrested at the G1 phase in the Rg1 group was significantly decreased compared with that in the γ-ray irradiation group (P<0.05). In conclusion, the present study indicates that Rg1 exerts anti-aging effects via the regulation of SIRT1-FOXO3 and SIRT3-SOD2 signaling pathways, and triggering the progression of Sca-1 HSC/HPCs from the G1 phase to the S phase in γ-ray irradiation-induced aging mice.
衰老的特征是代谢功能逐渐衰退。本研究旨在探讨人参皂苷Rg1（Rg1）对γ射线照射诱导的混合造血干细胞（HSCs）和造血祖细胞（HPCs）衰老的拮抗作用。将C57BL/6小鼠分为对照组、作为衰老小鼠模型的γ射线照射组和Rg1组。Rg1组在γ射线照射前7天以20 mg/kg/天的剂量用Rg1治疗。通过对小鼠进行6.5 Gy的γ射线全身照射建立衰老小鼠模型。使用衰老相关β-半乳糖苷酶（SA-β-Gal）染色试验检测从小鼠分离的干细胞抗原1阳性（Sca-1）HSC/HPCs。使用流式细胞术检测HSC/HPCs的细胞周期。还进行了混合造血祖细胞集落形成单位（CFU-mix）试验。使用蛋白质印迹法和逆转录定量PCR试验评估沉默调节蛋白1（SIRT1）、SIRT3、叉头框O3（FOXO3）和超氧化物歧化酶（SOD2）的mRNA和蛋白质表达水平。结果表明，与γ射线照射组相比，Rg1治疗显著增加了外周血中的白细胞、红细胞和血小板计数（P<0.05）。然而，Rg1显著减轻了γ射线照射衰老小鼠模型中Sca-1 HSC/HPCs的衰老。与γ射线照射组相比，Rg1组中SA-β-Gal染色的HSC/HPCs比例显著降低，CFU-Mix计数显著增加（P<0.05）。与γ射线照射组相比，Rg1显著增加了Sca-1 HSC/HPCs中SIRT1、SIRT3、FOXO3和SOD2的mRNA和蛋白质水平（P<0.05）。与γ射线照射组相比，Rg1组中停滞在G1期的Sca-1 HSC/HPCs百分比显著降低（P<0.05）。总之，本研究表明，Rg1通过调节SIRT1-FOXO3和SIRT3-SOD2信号通路发挥抗衰老作用，并在γ射线照射诱导的衰老小鼠中触发Sca-1 HSC/HPCs从G1期向S期的进展。
