探讨低浓度过氧化氢（H₂O₂）对创面愈合的促进作用及其可能的作用机制。

建立大鼠全层皮肤缺损创面模型，将大鼠分为对照组（使用生理盐水）、高、低浓度H₂O₂组（分别使用3﹪、0.01﹪H₂O₂干预）。选取第0、3、6、9、12、15、18天共7个时间点评估创面愈合率，并在第3、6、9天对创面组织样本进行组织病理检测。使用CCK-8法探索了不同浓度的H₂O₂对HaCat细胞增殖的影响。将细胞分为对照组、35 μmol/L H₂O₂组、35 μmol/L H₂O₂+ML385组3组[使用5 μmol/L的核因子E2相关因子2 （Nrf2）抑制剂ML385预处理]检测各组的细胞增殖活性，并使用免疫荧光法及流式细胞分析技术分别检测各组细胞内磷酸化Nrf2 （pNrf2）的核转位和活性氧（ROS）的水平。重复观测的创面愈合情况使用重复测量方差分析，多组间比较采用单因素方差分析，多个实验组与一个对照组间的比较采用Dunnett-t检验。

与对照组相比，0.01﹪H₂O₂组在3、6、9、12、15、18 d愈合率升高，使创面炎症期提前且缩短，3 ﹪H₂O₂组愈合率降低，差异具有统计学意义（P均< 0.05）。在细胞实验中，与对照组相比，25.92、43.2 μmol/L H₂O₂均可促进细胞增殖（吸光度：1.30±0.04比1.52±0.06、1.49±0.07），差异有统计学意义（P均< 0.05），故选取35 μmol/L H₂O₂进行接下来的实验。与35 μmol/L H₂O₂组相比，对照组和35 μmol/L H₂O₂+ML385组HaCat细胞的增殖活性（吸光度：1.47±0.05比1.30±0.05、1.23±0.06），pNrf2核转位（荧光强度：30.81±14.31比9.11±4.45、13.61±6.83）降低，差异有统计学意义（P < 0.05）。与对照组相比，35 μmol/L H₂O₂组和35 μmol/L H₂O₂+ML385组ROS水平升高（平均荧光强度：593.56±19.98比621.56±32.08、701.44±54.04）差异有统计学意义（P < 0.05）。

低浓度H₂O₂可通过提高细胞增殖活性促进创面愈合，且该过程受Nrf2调节。

To explore the promoting effect of low concentration hydrogen peroxide (H₂O₂) on wound healing and its possible mechanism.

In this study, the rat model of full-thickness skin defect was established, and the rats were divided into control group (using normal saline) , high concentration H₂O₂ group (3﹪H₂O₂ group) and low concentration H₂O₂ group (0.01﹪H₂O₂ group) . The wound healing rate was evaluated at 0, 3, 6, 9, 12, 15 and 18 days respectively, and the wound tissue samples were examined by histopathology at 3, 6 and 9 days. The CCK-8 method was used to explore the effects of different concentrations of H₂O₂ on the proliferation of HaCat cells. The cells were divided into control group, 35 mol/L H₂O₂ group and 35 mol/L H₂O₂+ML385 group [35 mol/L H₂O₂+ML385 group was pretreated with 5 μmol/L nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor ML385]. The nuclear transposition of phospho-Nrf2 (pNrf2) and reactive oxygen species (ROS) levels in each group were detected by immunofluorescence and flow cytometry, respectively. A repeated-measures ANOVA was used for statistical analysis of the wound closure. One-way ANOVA was used for comparison between multiple groups, and Dunnett-t test was used for comparison between multiple experimental groups and control group.

Compared with the control group, the healing rate of 0.01﹪ H₂O₂ group increased on the 3, 6, 9, 12, 15 and 18 days, which made the inflammatory period of wound earlier and shorter, while the healing rate of 3﹪ H₂O₂ group decreased, with statistical significance (all P < 0.05) . In the cell experiment, compared with the control group, 25.92 and 43.2 μmol/L H₂O₂ could promote cell proliferation (absorbance: 1.30±0.04 vs 1.52±0.06 and 1.49±0.07) , with statistical significance (all P < 0.05) . Therefore, H₂O₂ at an intermediate concentration of 35 μmol/L was selected for the next experiment. Compared with the 35 mol/L H₂O₂ group, the proliferative activity of HaCat cells in the control group and the 35 mol/L H₂O₂+ML385 group (absorbance: 1.47±0.05 vs 1.30±0.05 and 1.23±0.06) and the nuclear translocation of pNrf2 (fluorescence intensity: 30.81±14.31 vs 9.11±4.45 and 13.61±6.83) were significantly reduced (P < 0.05) . Compared with the control group, ROS levels in the 35 mol/L H₂O₂ group and the 35 mol/L H₂O₂+ML385 group were significantly higher (mean fluorescence intensity: 593.56±19.98 vs 621.56±32.08 and 701.44±54.04) , with statistical significance (P < 0.05) .

Low concentration H₂O₂ can promote wound healing by increasing the cell proliferation, and this process is regulated by Nrf2.