Effect Of N-acetylcysteine On HL-60 Cells Differentiation Suppression And 2-cys Peroxiredoxins Expression Induced By Hydroquinone

N-acetylcysteine (N - acetylcysteine - NAC) is a sulfur-based compoundsconstituting by L-cysteine and acetyl. It is also the intracellular cysteineand glutathione precursors. It was initially used in clinical studies forsputum dissolved in respiratory diseases. with the clinical research, andwas shown significant protective effect in AIDS, cancer, drugs and heavymetal poisoning, heart disease, smoking damage and other aspects infurther studies. it is a valuable and widely used drugs. HL-60 cell line isa human myeloid leukemia cell line. It was characteristic of myeloidprogenitor cells and has multipotent differentiation features. it can beinduced to differentiate to monocyte cells by treatment with TPA ,andthus has been used as a surrogate for a macrophage progenitor cell.Peroxiredoxins are the members of the family of antioxidant enzymeswhich is found in recent years. 2-Cys Prxs is a subclass. They can protectcells from oxygen free radical damage in the process of oxidative stressand also play an important role in cell proliferation and differentiation. Our previous study found that in the TPA-induced HL-60 celldifferentiation process, HQ plays an inhibitory effect, and HQ canincrease the expression of PrxI and PrxIII. My subject is to furtherexplore whether there is protective effects of NAC in the process of HQinhibition HL60 differentiation and the changes of 2- Cys Prx of geneexpression in this process.Objective To study the role of N-acetylcysteine (NAC) in the process ofinhibition of monocytic differentiation on HL-60 cells induced byhydroquinone (HQ) differentiated to monocytes, and to explore the geneexpression changes of 2- Cys Prx in this process.Methods HL -60 cells were cultured in IMDM culture mediumcontaining 200 mL / L fetal bovine serum , 100 kU / L penicillin , 100 mg/ L streptomycin . At 37°C, in an atmosphere of 5% CO2，passagedculture. Cells were collected after co-treated with 1-10mmol /L of NAC,50μmol /L of HQ and 20nmol /L of cardamom acid phorbol ester(TPA) for 48 h. Differentiation was assessed by the reduction of nitroblue tetrazolium assay; cell proliferation was detected by CCK-8; thechange of reactive oxygen species was assessed by reactive oxygenspecies test kit; 2- Cys Prxs expression was detected by fluorescencequantitative PCR and Western blot.Result Compared with the HQ group and TPA + HQ group, cell viabilitywas enhanced with the addition of NAC, the difference was statistically significant (P <0.01). In the process that HL-60 cells differentiated tomonocytes, compared with the TPA + HQ group, cell differentiation wasenhanced with the addition of NAC, the difference was statisticallysignificant (P <0.01), which NAC5mmol / L and NAC10mmol / L had themost significant difference. ROS detection showed that ,compared withthe control group, the intracellular reactive oxygen species of the HQgroup and the TPA + HQ group was significantly enhanced (P <0.01);compared with the TPA + HQ group, the intracellular reactive oxygenspecies of NAC groups at all doses was decreased significantly (P <0.01).That 5 time points measured the intracellular reactive oxygen specieslevels was significantly different, F=564.3, P<0.01. By western-blotanalysis detected results，compared with the control group，2-Cys Prxsprotein expression levels of the HQ group and the TPA + HQ group wassignificantly enhanced (P <0.01)；compared with the TPA + HQ group,2-Cys Prxs protein expression levels of NAC groups at all doses wasdecreased significantly (P <0.01), when the NAC concentration is 1mmol/ L, protein expression of PrxⅣhas no statistically significantdifference（p>0.05）.By the fluorescent quantitative PCR results,compared with the control group, 2-Cys Prxs gene expression of the HQgroup and the TPA + HQ group was significantly enhanced (P <0.01);compared with the TPA + HQ group, 2-Cys Prxs gene expression of NACgroups at all doses was decreased significantly (P <0.01). Conclusions HQ can inhibit HL-60 differentiation to monocytes. Thisinhibition would decrease with the increasing of the NAC’s dose, and thiseffect comes to achieve by clearing the intracellular reactive oxygenspecies. In the process of HQ inhibit HL -60 cell differentiation, NAC canreduce PrxI~IV gene expression and PrxIII、PrxⅣprotein expression of2-Cys Prxs family.