Objective To observe the effects of hydrogen peroxide on the expression of transforming growth factorβ1(TGF-β1) and Smad3 protein in A549 cells. Methods A549 cells were cultured with different concentrations of hydrogen peroxide. MTT assay was used to determine the cell growth and survival rates. The level of TGF-β1 and p-Smad3 protein were detected by western blotting. Results It was observed that hydrogen peroxide significantly inhibit proliferation of A549 cells. When the concentration of hydrogen peroxide was 1.0 mmol/L, the inhibition ratio reaches 46.34%, and the level of TGF-β1 and p-Smad3 protein were increased in a time-dependence manner and reached a peak after 24 h, then decreased a little but also remained at high level. Conclusions In the early oxidative damage, A549 cells express high level of TGF-β1 and p-Smad3 protein. It may be relevant to tissue repair and remodeling after lung injury.
Objective To observe the effects of cigarette smoke extract ( CSE) on the proliferation and secretion of hydrogen peroxide ( H2O2 ) in human lung fibroblasts ( HLFs) induced by transforming growth factor-β1 ( TGF-β1 ) . Methods Cultured HLFs were divided into a normal group and a model group induced by TGF-β1 ( 5 ng/mL) , then intervened with CSE at different concentrations ( 0% , 2. 5% , 5% ,10% , respectively) . Brdu ELISA assay was used to detect cell proliferation. H2O2 release from cultured cells was assayed using a fluorimetric method. Cellular localization of H2O2 and expression of α-SMA were performed using a fluorescent-labeling strategy. Results TGF-β1 stimulated group showed positive expression of α-SMA, implying TGF-β1 had induced fibroblasts to differentiate into myofibroblasts. In TGF-β1 stimulated group, 2. 5% and 5% CSE promoted cell proliferation ( P lt; 0. 01 or 0. 05) , while 10% CSE inhibited cell proliferation ( P lt; 0. 01) . In the normal group, both low and high concentration of CSE inhibited cell proliferation ( P lt; 0. 01 or P lt; 0. 05) , and the inhibition effect was dose-dependent. HLF induced by TGF-β1 generated low constitutive levels of extracellular H2O2 that was markedly enhanced by CSE treatment ( P lt; 0. 01) . Pretreatment with DPI, an inhibitor of NADPH oxidase, abolished secretion of H2O2 . Cellular localization of H2O2 by a fluorescent-labeling strategy demonstrated that extracellular secretion of H2O2 is specific to the myofibroblast. Conclusions Low concentration of CSE can promote myofibroblast proliferation, and markedly increase extracellular secretion of H2O2 . CSE possibly take part in the development and progress of idiopathic pulmonary fibrosis by increasing oxidative stress.
Objective To observe the effect of polypyramidine tract binding protein-associated splicing factor (PSF) on hydrogen peroxide (H2O2) induced apoptosis of retinal pigment epithelial (RPE) cells in vitro. Methods RPE cells were cultured and divided into a normal group, normal+H2O2 group, Vec+H2O2group, PSF+H2O2 group according to the experimental design. Overexpression of PSF in RPE cells were achieved by pEGFP-PSF plasmid transient transfection into RPE cells, then RPE cells were exposed to H2O2. The morphological changes were observed by hematoxylin-eosin (HE) staining and Live/Dead staining while the survival rate of cells was detected by MTT assay. The effect of PSF on H2O2-induced RPE apoptosis was analyzed by Cell Death Detection ELISA kit. Meanwhile, intracellular reactive oxygen species (ROS) level was detected by using DCFH-DA method. Results Overexpression of PSF could effectively alleviate the morphological changes induced by H2O2 stimulation shown by HE staining, and effectively reduce dead cells number shown by Live/Dead staining. After H2O2 stimulation, the survival rate, apoptosis rate and ROS production level in PSF overexpression group were 0.68±0.12, 0.44±0.08 and 18 616±3 382.54 respectively, showing significant difference in comparison with the vector plasmid group and normal group (P＜0.05). Conclusion PSF overexpression plays a protective role in H2O2-induced apoptosis by inhibiting the production of ROS in RPE cells.
ObjectiveTo observe the protective effect of dl-3-n-Butylphthalide (NBP) on apoptosis of retinal Müller cells induced by hydrogen peroxide (H2O2).MethodsHuman retinal Müller cells cultured in vitro were divided into normal control group, model group (H2O2 group) and experimental group (H2O2+NBP group). The cells in the H2O2 group and H2O2+NBP group were cultured with 200 μmol/L H2O2 for 2 h. Then the culture solution of the H2O2 group replace with complete medium and the H2O2+NBP group replace with complete medium containing 1 μmol/L NBP. The normal control group was a conventional cultured cells. Müller cells were identified by immunofluorescence staining. Hematoxylin-eosin (HE) staining was used to observe the apoptosis morphological changes. MTT assay was used to detect the activity of of retinal Müller cells after after 24 h and 48 h of NBP intervention. Hoechst33258 staining was used to observe the apoptosis. LIVE/DEAD ® cell activity/cytotoxicity kit was used to detect cell viability. Dichlorofluorescein diacetate (DCFH-DA) + endoplasmic reticulum (ER) red fluorescent probe (ER-Tracker Red) double staining was used to observe the expression level of reactive oxygen species (ROS) in ER of cells. One-way ANOVA combined with Dunnett statistical method were used for data analysis.ResultsHE staining showed that the number of cells in H2O2+NBP group was higher than that in H2O2 group. MTT assay showed that after 24 h and 48 h of NBP intervention, the differences in cell viability between the normal control group and the H2O2 group, the H2O2 group and the H2O2+NBP group were statistically significant (t=28.96, 3.658, 47.58, 20.33; P＜0.001, 0.022). The results of Hoechst33258 showed that the nuclear nucleus of a few cells in the H2O2+NBP group was crescent-shaped and the nuclear fragmentation was reduced, and the blue fluorescence of the remaining cells was uniform. The LIVE/DEAD ® cell activity/cytotoxicity kit showed that the number of dead cells with red fluorescence in the H2O2 group increased significantly, and the number of viable cells with green fluorescence decreased significantly. In the H2O2+NBP group, the number of viable cells with green fluorescence increased, and the number of dead cells with red fluorescence decreased. The double staining results of DCFH-DA+ER-Tracker Red showed that the green fluorescence intensity of H2O2 group was significantly enhanced; the green fluorescence intensity of H2O2+NBP group was lower than that of H2O2 group.ConclusionNBP alleviates H2O2-induced apoptosis of human retinal Müller cells by inhibiting ROS production.
ObjectiveTo investigate the effect of hydrogen peroxide on anti-infection and reducing postoperative drainage in multi-segmental lumbar surgery.MethodsA clinical data of 510 patients with multi-segmental lumbar degenerative diseases who were treated with surgery between January 2017 and January 2018 was retrospectively analyzed. In study group, the incisions of 230 cases were washed with hydrogen peroxide before suture. In control group, the incisions of 280 cases were washed with normal saline before suture. There was no significant difference in gender, age, lesion type, disease duration, operative segment, and other clinical data between the two groups (P>0.05). The operation time, intraoperative blood loss, postoperative drainage volume, and postoperative incidence of infection were recorded and compared between the two groups. The Centers for Disease Control and Prevention (CDC) standard was used to evaluate infection, which was divided into superficial infection and deep infection.ResultsAll operations completed successfully. There was no significant difference in operation time and intraoperative blood loss between the two groups (P>0.05). The postoperative drainage volume in the study group was significantly less than that in the control group (t=−2.990, P=0.005). A total of 13 patients developed infection after operation, including 10 cases of superficial infection (2 cases in the study group and 8 cases in the control group) with the infection time of (7.3±1.5) days, and 3 cases of deep infection (all in the control group) with the infection time of (16.6±3.1) days. The incidences of superficial and deep infections in the study group were lower than those in the control group, but there was no significant difference between the two groups (χ2=2.595, P=0.123; P=0.256). All the superficial infections were Staphylococcus aureus infection and recovered after active dressing change. Among the patients with deep infections, 2 cases were infected by Staphylococcus aureus and 1 case was infected by Escherichia coli; and the incisions healed after being washed and sutured thoroughly, and active dressing change.ConclusionThe incidence of postoperative infection and postoperative drainage volume can be reduced by washing the incision with hydrogen peroxide in multi-segmental lumbar surgery.
ObjectiveTo evaluate the efficiency of hydrogen peroxide vapor (HPV) in disinfecting multidrug-resistant organisms (MDROs).MethodsWe searched Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, China Science and Technology Journal Database for before-after studies or case-control studies or cohort studies evaluating efficiency of HPV and published from January 2010 to December 2020 (the time range was from January 2000 to December 2020 in the snowball searching). RevMan 5.4 and R 4.0.2 softwares were used for meta-analysis.ResultsA total of 9 studies were included, consisting of 8 before-after studies and 1 cohort study. Six studies evaluated positive rate of environmental samplings, meta-analysis revealed that HPV combined with manual cleaning disinfected the environment efficiently [relative risk (RR)=0.03, 95% confidence interval (CI) (0.01, 0.08), P< 0.000 01] and HPV was more efficient than manual cleaning [RR=0.04, 95%CI (0.02, 0.10), P< 0.000 01]. Three studies evaluated the hospital-acquired MDROs colonization/infection rates, and the results of the 3 studies were consistent, revealing that HPV could reduce hospital-acquired MDROs colonization/infection rates.ConclusionHPV is efficient in reducing MDROs contaminated surfaces and hospital-acquired infection rate.