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造血细胞来源于造血干细胞(HSC),而HSC分化呈明显等级关系。细胞中活性氧簇(ROS)对HSC维持至关重要,细胞内过多ROS会造成HSC衰老。细胞主要通过氧化还原酶以及抗氧化物调节胞内ROS水平达到稳态,从而避免过多的ROS对细胞损伤。细胞内的氧化还原酶有多种,包括过氧化氢酶(catalase)、锰-超氧化物歧化酶(MnSOD)、谷胱苷肽过氧化物酶(GPX1)、NQO1〔NAD(P)H dehydrogenenasequinone 1〕和硫氧还蛋白还原酶(TXNRD1),其在呈等级分化的各类血细胞中的活性及其在这些细胞中参与ROS水平的调节作用还不清楚。本研究应用流式细胞分选技术,分选出小鼠造血各系细胞,用半定量实时PCR法检测氧化还原酶基因(Catalase、MnSOD、GPX1、Txrnd1和Nqo1)在造血各系细胞中的表达,进而筛选出参与HSC中ROS调控的重要的氧化还原酶。结果表明,以长期HSC(LT-HSC)作为参照,T细胞中catalase基因表达是LT-HSC的0.14倍,显著减低(P<0.05)。CLP和髓系细胞中MnSOD基因的表达分别是LT-HSC的0.56和0.47倍,显著减低(P<0.05)。ST-HSC、GMP和髓系细胞中GPX1基因表达分别为LT-HSC的1.79、2.96和2.07倍,显著增加(P<0.05);MEP、T淋巴细胞和B淋巴细胞中GPX1基因表达分别为LT-HSC的0.58、0.10和0.6倍,显著减低(P<0.05)。ST-HSC、MPP、CMP、GMP和髓系细胞中Txrnd1的表达分别为LT-HSC的3.36、3.18、4.19、6.39和4.27,显著增加(P<0.05);T淋巴细胞和B淋巴细胞中Txrnd1的表达分别为LT-HSC的0.016和0.56倍,显著减低(P<0.05)。ST-HSC、MPP、CMP、GMP、CLP和B淋巴细胞中Nqo1的表达为LT-HSC的0.30、0.17、0.25、0.10、0.04和0.01倍,显著减低(P<0.05)。结论:氧化还原酶在造血各系细胞的表达差异较大,提示在不同细胞中发挥主要作用的氧化还原酶种类不同。更为重要的是,Nqo1在LT-HSC中表达明显高于其他各系,提示其可能通过调控Nqo1的表达调节HSC功能。
Hematopoietic cells derived from hematopoietic stem cells (HSC), while HSC differentiation showed a clear hierarchical relationship. Reactive oxygen species (ROS) in cells is crucial for HSC maintenance. Excessive intracellular ROS can cause HSC aging. Cells regulate homeostasis via intracellular ROS levels mainly through oxidoreductases and antioxidants, thus avoiding excessive ROS damage to cells. There are many intracellular oxidoreductases, including catalase, manganese-superoxide dismutase (MnSOD), glutathione peroxidase (GPX1), NQO1 [NAD (P) H dehydrogenenasequinone 1], and thioredoxin reductase (TXNRD1), their activity in various classes of blood cells that are differentiated and their role in the regulation of ROS levels in these cells is unclear. In this study, the hematopoietic lineage cells were sorted by flow cytometry. The expression of catalase (MnSOD, GPX1, Txrnd1 and Nqo1) in hematopoietic lineage cells was detected by semi-quantitative real-time PCR , And then screened important oxidoreductases involved in ROS regulation in HSCs. The results showed that the expression of catalase gene in T cells was 0.14-fold lower than that of LT-HSC (P <0.05), with the reference of long-term HSC (LT-HSC) The MnSOD gene expression in CLP and myeloid cells was significantly reduced (P <0.05) by 0.56 and 0.47 times that of LT-HSC, respectively. The GPX1 gene expression in ST-HSC, GMP and myeloid cells was 1.79, 2.96 and 2.07 fold higher than that of LT-HSC respectively (P <0.05). The GPX1 gene expression in MEP, T lymphocytes and B lymphocytes were respectively LT -HSC 0.58, 0.10 and 0.6 times, significantly lower (P <0.05). The expression of Txrnd1 in ST-HSC, MPP, CMP, GMP and myeloid cells was significantly increased (P <0.05) compared with that of LT-HSC in 3.36,3.18,4.19,6.39 and 4.27, respectively. The levels of Txrnd1 in T lymphocytes and B lymphocytes The expression of LT-HSC was 0.016 and 0.56 fold, respectively, significantly lower (P <0.05). The expression of Nqol in ST-HSC, MPP, CMP, GMP, CLP and B lymphocytes was significantly reduced (P <0.05) at 0.30, 0.17, 0.25, 0.10, 0.04 and 0.01 times that of LT-HSCs. CONCLUSION: The expression of oxidoreductase in hematopoietic cells varies widely, suggesting different types of oxidoreductases that play a major role in different cells. More importantly, Nqo1 expression in LT-HSC was significantly higher than other lines, suggesting that it may regulate HSC function by regulating Nqo1 expression.