Objective To observe the effect of high expression of polypyrimidine tract-binding protein-associated splicing factor (PSF) on low concentration of 4-hydroxynonenal (4-HNE) induced human retinal microvascular endothelial cells (HRMECs), and explore the possible mechanism. MethodsThe HRMECs cultured in vitro were divided into 4-HNE treated group, PSF overexpression group combined with 4-HNE group (PSF+4-HNE group), PSF overexpression+ML385 treatment combined with 4-HNE group (PSF+ML385+4-HNE group), and 4-HNE induced PSF overexpression group with LY294002 pretreatment (LY294002+4-HNE+PSF group). Cell culture medium containing 10 μmmol/L 4-HNE was added into 4-HNE treatment group, PSF+4-HNE group, PSF+ML385+4-HNE group for 12 hours to stimulate oxidative stress. 1.0 μg of pcDNA-PSF eukaryotic expression plasmid were transfected into PSF+4-HNE group and PSF+ML385+4-HNE group to achieve the overexpression of PSF. Also cells were pretreated with ML385 (5 μmol/L) for 48 hours in the PSF+ML385+4-HNE group, meanwhile within the LY294002+4-HNE+PSF group, after pretreatment with LY294002, cells were treated with plasmid transfection and 4-HNE induction. Transwell detects the migration ability of PSF to HRMECs. The effect of PSF on the lumen formation of HRMECs was detected by using Matrigel in vitro three-dimensional molding method. Flow cytometer was used to detect the effect of PSF overexpression on reactive oxygen (ROS) level in HRMECs. Protein immunoblotting was used to detect the relative expression of PSF, nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1) protein, and phosphoserine threonine protein kinase (pAkt) protein. The comparison between the two groups was performed using a t-test. ResultsThe number of live cells, migrating cells, and intact lumen formation in the 4-HNE treatment group and the PSF+4-HNE group were 1.70±0.06, 0.80±0.13, 24.00±0.58, 10.00±0.67, and 725.00±5.77, 318.7±12.13, respectively. There were significant differences in the number of live cells, migrating cells, and intact lumen formation between the two groups (t=12.311, 15.643, 17.346; P＜0.001). The results of flow cytometry showed that the ROS levels in the 4-HNE treatment group, PSF+4-HNE group, and PSF+ML385+4-HNE group were 816.70±16.67, 416.70±15.44, and 783.30±17.41, respectively. There were statistically significant differences between the two groups (t=16.311, 14.833, 18.442; P＜0.001). Western blot analysis showed that the relative expression levels of pAkt, Nrf2, and HO-1 proteins in HRMECs in the 4-HNE treatment group, PSF+4-HNE group and LY294002+4-HNE+PSF group were 0.08±0.01, 0.57±0.04, 0.35±0.09, 0.17±0.03, 1.10±0.06, 0.08±0.11 and 0.80±0.14, 2.50±0.07, 0.50±0.05, respectively. Compared with the PSF+4-HNE group, the relative expression of pAkt, Nrf2, and HO-1proteins in the LY294002+4-HNE+PSF group decreased significantly, with significant differences (t=17.342, 16.813, 18.794; P＜0.001). ConclusionPSF upregulates the expression of HO-1 by activating the phosphatidylinositol 3 kinase/Akt pathway and inhibits cell proliferation, migration, and lumen formation induced by low concentrations of 4-HNE.
Reactive oxygen species (ROS) play an important role in the pathogenesis of various cardiovascular diseases, by leading to cell apoptosis and thus causing organic injuries. Anti-ROS therapy is highly anticipated, but currently, there is still no appropriate prevention method. Studies have shown that thioredoxin (Trx), being a kind of significant endogenous antioxidant system, has excellent antioxidant capacity. Promotion of Trx can reduce key biomolecules to eliminate ROS or regulate many signaling pathways, thus resisting ROS injuries, which may be a new anti-ROS strategy. Therefore, we reviewed the research progress of Trx in cardiac antioxidant therapy to discuss its potential and possibility to be a target for prevention of heart-related ROS injury.
Objective To explore the potential protective effect in vivo of Edaravone, a free radical scavenger on model of acute lung injury in rats with sepsis. Methods Twenty-four male Wistar rats were randomly divided into three groups, ie. a control group( NS group) , a model group( LPS group) , a Edaravone treatment group( ED group) . ALI was induced by injecting LPS intravenously( 10 mg/ kg) in the LPS group and the ED group. Meanwhile the ED group was intravenously injected with Edaravone( 3 mg/ kg) . The NS group was injected with normal saline as control. The lung tissue samples were collected at 6 h after intravenous injection. The wet / dry ( W/D) weight ratio of lung tissue was measured. The levels of myeloperoxidase ( MPO) , malondialdehyde ( MDA ) and superoxide dismutase ( SOD) in lung tissue homogenate were assayed. The pathological changes and expression of nuclear factor-kappa B( NF-κB) in lung tissue were also studied. Results Compared with the NS group, The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the LPS group were significantly higher( all P lt; 0. 01) , and the level of SOD was apparently lower( P lt; 0. 01) . The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the ED group were significantly lower than those in the LPS group( all P lt; 0. 01) and higher than those in the NS group( all P lt; 0. 01) . And the level of SOD in lung tissue of the ED group was higher than that in the LPS group and lower than that in the NS group ( P lt; 0. 01) . Conclusions Edaravone has protective effect on ALI rat model. The mechanismmay be related to its ability of clearing the reactive oxygen species, inhibiting the activation of the signal pathway of NF-κB and inflammatory cascade.
Lung cancer is the leading cause of cancer-related deaths worldwide. Despite the development and use of several targeting drugs for lung cancer therapy, the five-year survival rate has remained as low as 15% for the past three decades. Cisplatin-based chemotherapy is considered the first-line therapeutic strategy for lung cancer. However, developments of chemoresistance is a major obstacle for the successful treatment. Therefore, the development of novel therapy against cisplatin-resistance lung cancer is imperative. Photodynamic therapy (PDT), which is a non-invasive combinatorial therapeutic modality using light, photosensitizer (PS) and oxygen, may provide an unprecedented tool to develop more effective treatments. To provide experimental basis for its application in cisplatin-resistance lung cancer, we will discuss the biological effects of MPPa-photodynamic therapy in human cisplatin-resistance lung cancer cells in this article. Human cisplatin-resistance lung cancer cells A549/DDP were co-cultured with MPPa (0, 1, 2, 4, 8, 16 μmol/L) and exposed to light (0, 0.6, 1.2, 2.4, 3.6, 4.8 J/cm2), and cell viability was determined with CCK-8 assay. Flow cytometry was used to detect apoptosis, DCFH-DA staining was employed to observe reactive oxygen species (ROS), and Western blot was used to detect the expressions of B-cell lymphoma-2 (Bcl-2) protein and Bcl-2 associated X protein (Bax). The proliferation of A549/DDP cells was suppressed by PDT. The apop-totic rate in the PDT group was significantly higher than that in the control, MPPa or light group (P < 0.05). The level of ROS was increased. The expression of Bax was increased, and that of Bcl-2 was decreased. MPPa-photodynamic therapy can significantly suppress cell viability, and induce apoptosis in human cisplatin-resistance lung cancer cells.
Objective To investigate the antioxidant and osteogenic induction capabilities of calcium phosphate nanoflowers (hereinafter referred to as nanoflowers) in vitro at different concentrations. Methods Nanoflowers were prepared using gelatin, tripolyphosphate, and calcium chloride. Their morphology, microstructure, elemental composition and distribution, diameter, and molecular constitution were characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive spectroscopy. Femurs and tibias were harvested from twelve 4-week-old Sprague Dawley rats, and bone marrow mesenchymal stem cells (BMSCs) were isolated and cultured using the whole bone marrow adherent method, followed by passaging. The third passage cells were identified as stem cells by flow cytometry and then co-cultured with nanoflowers at concentrations of 0, 0.4, 0.8, 1.2, 1.6, 2.0, 2.4, 2.8, 3.2, and 3.6 mg/mL. Cell counting kit 8 (CCK-8) assay was performed to screen for the optimal concentration that demonstrated the best cell viability, which was subsequently used as the experimental concentration for further studies. After co-culturing BMSCs with the screened concentration of nanoflowers, the biocompatibility of the nanoflowers was verified through live/dead cell staining, scratch assay, and cytoskeleton staining. The antioxidant capacity was assessed by using reactive oxygen species (ROS) fluorescence staining. The in vitro osteoinductive ability was evaluated via alkaline phosphatase (ALP) staining, alizarin red staining, and immunofluorescence staining of osteocalcin (OCN) and Runt-related transcription factor 2 (RUNX2). All the above indicators were compared with the control group of normally cultured BMSCs without the addition of nanoflowers. Results Scanning electron microscopy revealed that the prepared nanoflowers exhibited a flower-like structure; transmission electron microscopy scans discovered that the nanoflowers possessed a multi-layered structure, and high-magnification images displayed continuous atomic arrangements, with the nanoflower diameter measuring (2.00±0.25) μm; energy-dispersive spectroscopy indicated that the nanoflowers contained elements such as C, N, O, P, and Ca, which were uniformly distributed across the flower region; Fourier transform infrared spectroscopy analyzed the absorption peaks of each component, demonstrating the successful preparation of the nanoflowers. Through CCK-8 screening, the concentrations of 0.8, 1.2, and 1.6 mg/mL were selected for subsequent experiments. The live/dead cell staining showed that nanoflowers at different concentrations exhibited good cell compatibility, with the 1.2 mg/mL concentration being the best (P<0.05). The scratch assay results indicated that the cell migration ability in the 1.2 mg/mL group was superior to the other groups (P<0.05). The cytoskeleton staining revealed that the cell morphology was well-extended in all concentration groups, with no significant difference compared to the control group. The ROS fluorescence staining demonstrated that the ROS fluorescence in all concentration groups decreased compared to the control group after lipopolysaccharide induction (P<0.05), with the 1.2 mg/mL group showing the weakest fluorescence. The ALP staining showed blue-purple nodular deposits around the cells in all groups, with the 1.2 mg/mL group being significantly more prominent. The alizarin red staining displayed orange-red mineralized nodules around the cells in all groups, with the 1.2 mg/mL group having more and denser nodules. The immunofluorescence staining revealed that the expressions of RUNX2 and OCN proteins in all concentration groups increased compared to the control group, with the 1.2 mg/mL group showing the strongest protein expression (P<0.05). Conclusion The study successfully prepares nanoflowers, among which the 1.2 mg/mL nanoflowers exhibits excellent cell compatibility, antioxidant properties, and osteogenic induction capability, demonstrating their potential as an artificial bone substitute material.
Objective To explore the role of ROS/ Src / JNK signaling pathway in cigarette smoke extract( CSE) -induced mucin ( MUC) 5AC production in A549 airway epithelial cells. Methods The A549 airway epithelial cells were cultured in medium with CSE, then treated with ROS scavenger DMTU, c-Jun Nterminal kinase( JNK) specific inhibitor SP600125, and Src kinase inhibitor PP2, respectively. The relative content of reactive oxygen species( ROS) were assayed by special kit. The levels of MUC5AC in culture medium, epidermal growth factor receptor( EGFR) , activated EGFR and MUC5AC mRNA in culture cells were detected with ELISA,Western Blot and RT-PCR, respectively. Results A dose-dependent increasing of ROS production in cells exposed to dilutions of cigarette smoke solution was detected. DMTU inhibited cigarette smoke-induced Src phosphorylation( P lt; 0. 05) . SP600125 reduced the expression of MUC5AC ( P lt; 0. 05) compared with the normal group. The activation of JNK was suppressed by Src specific inhibitor PP2( P lt; 0. 05) . Conclusion ROS/ Src / JNK signal cascade may play a particular role in MUC5AC expression of A549 cells induced by cigarette smoke.
Objective
To investigate the protective effect of the antioxidant glutathione (GSH) on the steroid-induced imbalance between osteogenesis and adipogenesis in human bone marrow mesenchymal stem cells (BMSCs).
Methods
The BMSCs were isolated from the proximal femur bone marrow from 3 patients of femoral neck fracture and were separated, cultured, and purificated by density gradient centrifugation and adherent wall methodin vitro. The third generation BMSCs were divided into 5 groups: group A, BMSCs (1×105 cells/mL); group B, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone; group C, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+5 μmol/L GSH; group D, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+10 μmol/L GSH; group E, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+50 μmol/L GSH. After cultured for 7 days, the reactive oxygen species expression was detected by flow cytometry; the superoxide dismutase (SOD) and Catalase mRNA expressions were determined by RT-PCR; the peroxisome proliferator-activated receptors γ (PPAR-γ), CCAAT/enhancer-binding family of proteins (C/EBP), Runx2, and alkaline phosphatase (ALP) mRNA expressions were evaluated by real-time fluorescence quantitative PCR. After cultured for 21 days, Oil red O staining was used to observe the adipogenesis differentiation of cells, and the expressions of related proteins were detected by Western blot.
Results
The reactive oxygen species expression in group B was obviously higher than in the other groups, in group C than in groups A, D, and E, and in groups D, E than in group A, all showing significant differences between groups (P<0.05); but there was no significant difference between groups D and E (P>0.05). The oil red O staining positive cells in group B were obviously more than the other groups, and groups C, D, E, and A decreased sequentially, the absorbance (A) values had significant differences between groups (P<0.05). RT-PCR detection showed that the relative expressions of SOD and Catalase mRNA in group B were significantly lower than those in the other groups, while in group C than in groups A, D, and E (P<0.05), but there was no significant difference among groups A, D, and E (P>0.05). Real-time fluorescence quantitative PCR detection showed that the relative expressions of PPAR-γ and C/EBP mRNA in group B were significantly higher than those in the other groups, while in group C than in groups A, D, and E, and in groups D, E than in group A (P<0.05); but there was no significant difference between groups D and E (P>0.05). The relative expressions of Runx2 and ALP mRNA in group B were significantly lower than those in the other groups, while in group C than in groups A, D, and E, and in groups D, E than in group A (P<0.05); but there was no significant difference between groups D and E (P>0.05). Western blot detection showed that the relative expression of PPAR-γ and C/EBP protein in group B was significantly higher than those in the other groups, and groups C, D, E, and A decreased sequentially, all showing significant differences between groups (P<0.05). The relative expression of Runx2 and ALP protein in group B was significantly lower than those in the other groups, and groups C, D, E, and A increased sequentially, all showing significant differences between groups (P<0.05).
Conclusions
GSH can inhibit the adipogenesis differentiation and enhance the osteogenic differentiation of human BMSCs by reducing the intracellular reactive oxygen species level; and in a certain range, the higher the concentration of GSH, the more obvious the effect is.
ObjectiveGelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA)/chitosan oligosaccharide (COS) hydrogel was used to construct islet biomimetic microenvironment, and to explore the improvement effect of GelMA/HAMA/COS on islet activity and function under hypoxia. Methods Islets cultured on the tissue culture plate was set as the control group, on the GelMA/HAMA/COS hydrogel with COS concentrations of 0, 1, 5, 10, and 20 mg/mL respectively as the experimental groups. Scanning electron microscopy was used to observe the microscopic morphology, rheometer test to evaluate the gel-forming properties, contact angle to detect the hydrophilicity, and the biocompatibility was evaluated by the scaffold extract to L929 cells [using cell counting kit 8 (CCK-8) assay]. The islets were extracted from the pancreas of 8-week-old Sprague Dawley rats and the islet purity and function were identified by dithizone staining and glucose-stimulated insulin secretion (GSIS) assays, respectively. Islets were cultured under hypoxia (1%O2) for 24, 48, and 72 hours, respectively. Calcein-acetyl methyl/propidium iodide (Calcein-AM/PI) staining was used to evaluate the effect of hypoxia on islet viability. Islets were cultured in GelMA/HAMA/COS hydrogels with different COS concentrations for 48 hours, and the reactive oxygen species kits were used to evaluate the antagonism of COS against islet reactive oxygen species production under normoxia (20%O2) and hypoxia (1%O2) conditions. Calcein-AM/PI staining was used to evaluate the effect of COS on islet activity under hypoxia (1%O2) conditions. Islets were cultured in tissue culture plates (group A), GelMA/HAMA hydrogels (group B), and GelMA/HAMA/COS hydrogels (group C) for 48 hours, respectively. Immunofluorescence and GSIS assays were used to evaluate the effect of COS on islet activity under hypoxia (1%O2) conditions, respectively. Results GelMA/HAMA/COS hydrogel had a porous structure, the rheometer test showed that it had good gel-forming properties, and the contact angle test showed good hydrophilicity. CCK-8 assay showed that the hydrogel in each group had good biocompatibility. The isolated rat islets were almost round, with high islet purity and insulin secretion ability. Islets were treated with hypoxia for 24, 48, and 72 hours, Calcein-AM/PI staining showed that the number of dead cells gradually increased with time, which were significantly higher than those in the non-hypoxia-treated group (P<0.001). Reactive oxygen staining showed that GelMA/HAMA/COS hydrogels with different COS concentrations could antagonize the production of reactive oxygen under normal oxygen and hypoxia conditions, and this ability was positively correlated with COS concentration. Calcein-AM/PI staining indicated that GelMA/HAMA/COS hydrogels with different COS concentrations could improve islet viability under hypoxia conditions, and cell viability was positively correlated with COS concentration. Immunofluorescence staining showed that GelMA/HAMA/COS hydrogel could promote the expression of islet function-related genes under hypoxia conditions. GSIS assay results showed that the insulin secretion of islets in hypoxia condition of group C was significantly higher than that of groups B and C (P<0.05). Conclusion GelMA/HAMA/COS hydrogel has good biocompatibility, promotes islet survival and function by inhibiting reactive oxygen species, and is an ideal carrier for building islet biomimetic microenvironment for islet culture and transplantation.
ObjectiveTo investigate the role of p22phox and NOX5 in autophagy and apoptosis of osteoblasts induced by hypoxia.MethodsThe skull tissue of newborn rats was cut into small pieces, and the osteoblasts were separated and purified by the tissue block adherent method and the differential adherent method. The first generation cells were harvested and identified by HE staining, Alizarin red staining, alkaline phosphatase (ALP) staining, and flow cytometry. A three-gas incubator was used to prepare a hypoxia model of osteoblasts. At 0, 3, 6, 12, and 24 hours of hypoxia, the expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ were detected by Western blot, and the level of reactive oxygen species (ROS) and cell apoptosis rate were detected by flow cytometry. And the time point of the highest level of ROS was selected as the hypoxia time point for subsequent experiments. The first generation osteoblasts were divided into normal group, si-p22phox hypoxia group, and si-NOX5 hypoxia group and subjected to corresponding transfection and hypoxia treatment. The inhibition efficiency of si-p22phox and si-NOX5 were detected by RT-PCR. Then the osteoblasts were divided into normal group, si-NC hypoxia group, si-p22phox hypoxia group, and si-NOX5 hypoxia group. After transfection and hypoxia treatment, Western blot was used to detect the expressions of p22phox, NOX5, autophagy-related proteins (LC3Ⅱ/Ⅰ, Beclin), and apoptosis-related proteins (Bcl-2, Bax), and flow cytometry was used to detect the cell apoptosis rate and level of ROS. The first generation osteoblasts were divided into a hypoxia group for 12 hours (hypoxia group) and a group that simultaneously inhibited si-p22phox and si-NOX5 and hypoxia for 12 hours (inhibition+hypoxia group). The expressions of Beclin and Bax were observed by immunofluorescence staining after the corresponding treatment.ResultsAfter identification, the isolated cells were osteoblasts. After hypoxia treatment, the relative expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ proteins and the apoptosis rate of osteoblasts gradually increased (P<0.05), and the level of ROS also significantly increased (P<0.05) and reached the peak value at 12 hours. The 12-hour hypoxia model was selected for subsequent experiments. Silencing the p22phox gene did not affect the expression of NOX5, and silencing the NOX5 gene did not affect the expression of p22phox. Compared with hypoxia treatment, the relative expressions of LC3Ⅱ/Ⅰ, Beclin, and Bax proteins after inhibiting the expression of p22phox or NOX5 gene significantly decreased (P<0.05), the relative expression of Bcl-2 protein significantly increased (P<0.05), the cell apoptosis rate and level of ROS also significantly decreased (P<0.05). After silencing the expressions of p22phox and NOX5 genes at the same time, the immunofluorescence staining showed that the fluorescence of Beclin and Bax were weak.ConclusionInhibiting the expressions of p22phox and NOX5 genes can reduce the level of ROS in osteoblasts under hypoxia-induced conditions, and at the same time reduce autophagy and apoptosis, especially attenuate the excessive apoptosis of cells in the early to late stages, and strengthen the hypoxic osteoblasts proliferation.
ObjectiveTo investigate the effects of targeted regulation of SMAD9 expression by bone morphogenetic protein 4 (BMP4) on Müller cell migration, reactive oxygen species (ROS) generation and vascular endothelial growth factor (VEGF) expression. MethodsMüller cells cultured in vitro were divided into normal control group, BMP4 group, BMP4+ no-load plasmid group (BMP4+NC group) and BMP4+SMAD9 small interference plasmid group (BMP4+siSMAD9). Cells in BMP4 group, BMP4+NC group and BMP4+siSMAD9 group were induced by adding 100 ng/ml BMP4 into cell medium for 24 h. Subsequently, BMP4+NC group was transfected with empty plasmid. BMP4+siSMAD9 group was transfected with SMAD9 small interference plasmid for 48 h. The effect of BMP4 on Müller cell migration was determined by cell scratch test. The effect of BMP4 on the production of ROS in Müller cells was detected by flow cytometry. Western blots and real-time quantitative fluorescence polymerase chain reaction (qPCR) were used to detect the relative mRNA expression levels of glutamine synthetase (GS) and glial fibrinoacidic protein (GFAP) in Müller cells. VEGF expression in Müller cells was detected by immunofluorescence. One-way analysis of variance was used to compare groups. ResultsThe results of cell scratch test showed that the cell mobility of BMP4+siSMAD9 group was significantly lower than that of BMP4 and BMP4+NC group, and the difference was statistically significant (F=68.319, P＜0.001). Flow cytomethods showed that the level of ROS in BMP4+siSMAD9 group was significantly lower than that in BMP4 and BMP4+NC group, and the difference was statistically significant (F=52.158, P＜0.001). Western blot and qPCR results showed that the protein levels of GS and GFAP (F=42.715, 36.618) and mRNA relative expression levels (F=45.164, 43.165) in BMP4+siSMAD9 group were significantly lower than those in BMP4 and BMP4+NC group. The difference was statistically significant (P＜0.01). The results of immunofluorescence detection showed that the intracellular VEGF fluorescence intensity in BMP4 group and BMP4+NC group was significantly higher than that in BMP4+siSMAD9 group, and the difference was statistically significant (F=46.384, P＜0.05). ConclusionTargeted regulation of SMAD9 expression by BMP4 can up-regulate VEGF expression and promote the migration and ROS production of Müller cells.
