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.
ObjectiveTo investigate the molecular mechanism by which metastasis-associated protein 3 (MTA3) participates in glioma resistance through reactive oxygen species. Methods Protein expression in glioma stem cells (GSCs) and non-GSCs was detected using Western blotting. GSCs included U87 and SHG44 cells, while non-GSCs included U87s and SU-2 cells. After overexpressing MTA3, U87 and SHG44 cells were divided into Lv-scr and Lv-MTA3 groups. The self-renewal capacity of glioma cells was assessed through a neurosphere formation assay. Cell survival fractions were examined following exposure to 0, 2, 4, 6, 8, and 10 Gy X-ray irradiation under normoxic or hypoxic conditions. Apoptosis and reactive oxygen species expression were analyzed using flow cytometry. Immunofluorescence staining was performed to detect the stem cell markers CD133 and nestin, as well as the differentiation markers glial fibrillary acidic protein (GFAP, for astrocytes) and neuronal class Ⅲ β-tubulin. Results In GSCs, MTA3 expression was lower in the U87s and SU-2 groups. After MTA3 overexpression, Lv-MTA3 expression was higher in U87s and SU-2 compared to the Lv-scr group. Under normoxic or hypoxic conditions, U87 and SU-2 showed greater radioresistance compared to glioma cell lines U87 and SHG44. Compared to non-GSCs, basal reactive oxygen species formation was reduced in GSCs, while reactive oxygen species generation was increased in non-GSCs. Following exposure to different doses of X-rays under normoxic or hypoxic conditions, GSCs with MTA3 overexpression exhibited greater radiosensitivity than those with stable integration. Additionally, MTA3 overexpression slightly increased the oxygen enhancement ratio (OER) in GSCs. MTA3 overexpression reduced the immunoreactivity of CD133 and nestin in both stem cell lines, and increased immunofluorescence staining of GFAP and neuronal class Ⅲ β-tubulin, with statistically significant differences (P<0.05). Conclusions MTA3 is downregulated in GSCs. Overexpression of MTA3 reduces the radioresistance and stemness of GSCs both in vitro and in vivo. MTA3 plays a crucial role in regulating the radiosensitivity and stemness of GSCs through reactive oxygen species.
Objective Glucocorticoid is the main cause of non-traumatic avascular necrosis of femoral head. To explore the changes of reactive oxygen species (ROS) in the bone microvascular endothel ial cells treated with glucocorticoid so as to investigate the pathogenesis of steroid-induced avascular necrosis of femoral head. Methods The cancellous bone of femoral head was harvested from voluntary donators undergoing total hip arthroplasty, and then the bone microvascular endothel ial cells were isolated by enzyme digestion. The cells at passage 3 were cocultured with different concentrations of hydrocortisone (0, 0.03, 0.10, 0.30, and 1.00 mg/mL) for 24 hours. MTT assay was used for the inhibitory rate of cell prol iferation, flow cytometry for apoptosis rate, and fluorescence probe for the production of ROS and xanthine oxidase (XOD). Results At 2-3 days primary culture, the cells were spindle and arranged l ike cobbles and they reached confluence after 1 week. The inhibitory rates of cell prol iferation in 0.03, 0.10, 0.30, and 1.00 mg/mL groups were 20.22% ± 2.97%, 22.94% ± 4.52%, 43.98% ± 3.35%, and 78.29% ± 3.85%, respectively; and 2 high-concentration groups (0.30 and 1.00 mg/mL groups) were significantly higher (P lt; 0.05) than 2 low-concentration groups (0.03 and 0.10 mg/mL groups). The apoptosis rates in 0, 0.03, 0.10, 0.30, and 1.00 mg/mL groups were 0.10% ± 0.01%, 0.23% ± 0.02%, 1.83% ± 0.04%, 6.34% ± 0.11%, and 15.33% ± 0.53%, respectively; 2 high-concentration groups (0.30 and 1.00 mg/mL groups) were significantly higher (P lt; 0.05) than 0 mg/mL group. In 0, 0.30, and 1.00 mg/ mL groups, the ROS levels were 57.35 ± 7.11, 120.47 ± 15.68, and 166.15 ± 11.57, respectively, and the XOD levels were 0.017 9 ± 0.000 9, 0.028 3 ± 0.001 7, and 0.067 7 ± 0.004 1, respectively; there were significant differences in the levels of ROS and XOD among 3 groups (P lt; 0.05). Conclusion Increasing of ROS production in bone microvascular endothel ial cells can be induced by high concentration glucocorticoid, and it can result in cell injury
ObjectiveTo investigate the effects of interferon gene stimulating protein (STING) inhibitor (C176) on human retinal microvascular endothelial cells (hRMEC) under oxidative stress. MethodsAn animal experimental study. In vivo experiment: 48 healthy male C57BL/6J mice were randomly divided into wild type mice group (WT group) and diabetes (DM) group, with 24 mice in each group. DM mice were induced by streptozotocin to establish DM model. After successful modeling, DM group was divided into DM+dimethyl sulfoxide (DMSO) group and DM+C176 group, with 12 mice in each group. The mice in the DM+DMSO group were intraperitoneally injected with DMSO at the dose of 50 mg/kg. Mice in DM+C176 group were intraperitoneally injected with STING inhibitor C176 750 nmol at the dose of 50 mg/kg. Four weeks after modeling, immunohistochemical staining, Western blot and real-time fluorescence quantitative polymerase chain reaction were used to detect the expression of STING in the retina of WT and DM mice. The leukocyte adhesion test was used to detect the number of leukocytes adhering to hRMEC in mice with WT, DM+DMSO and DM+C176 groups. In vitro experiment: hRMEC was randomly divided into conventional culture cell group (N group), dimethyl sulfoxide (DMSO) group (with DMSO intervention) and C176 group (with C176 intervention). The cells were induced by 150 μg/ml glycation end products for each group. In vitro leukocyte adhesion test combined with 4', 6-diamino-2-phenylindole staining was used to detect the number of leukocytes adhering to hRMEC. The adherent leukocytes were quantitatively analyzed by flow cytometry; H2DCFDA/reactive oxygen species (ROS) fluorescence probe was used to detect ROS expression in cells; Seahorse XFe96 cell energy metabolism analyzer was used to measure the level of intracellular glycolysis. t-test was used to compare the two groups; single factor analysis of variance was used to compare the three groups. ResultsIn vivo experiment: compared with WT group, the expression level of STING (t=73.248) and the relative expression amount of mRNA (t=67.385) in the retina of DM group mice increased significantly (P＜0.05). Compared with WT group, the number of leukocytes adhering to the retinal vessels of mice in DM+DMSO group was significantly increased, while that in DM+C176 group was significantly decreased (F=84.352, P＜0.01). In vitro: compared with N group and DMSO group, the number of leukocyte adhesion on hRMEC in C176 group decreased significantly (F=35.251, P＜0.01). Compared with N group, the number of leukocytes adhering to hRMEC in DMSO group and C176 group decreased significantly (F=26.374, P＜0.01). The ROS level in hRMEC in C176 group was significantly lower than that in N group and C176 group (F=41.362, P＜0.01). Compared with N group and DMSO group, the glycolysis level of hRMEC in C176 group was significantly reduced, with a statistically significant difference (F=68.741, P＜0.01). ConclusionInhibiting the expression of STING in retinal vascular endothelial cells can improve the progress of DM by inhibiting leukocyte adhesion, ROS production and glycolysis level.
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.
Objective To investigate the expression of heme oxygenase-1 (HO-1) by high glucose treatment in human lung epithelial A549 cells. Methods The effect of high glucose on the expression of HO-1 in A549 cells was investigated with Western blot and reverse transcription PCR. HO-1 enzymic activity and reactive oxygen species (ROS) production were investigated with enzyme-linked immunosorbent test. Results Treatment with 25 mmol/L high glucose for 0, 24 h, 48 h, 72 h and in concentrations of 5 mmol/L, 10 mmol/L, 25 mmol/L, 40 mmol/L for 48 h induced increased expression on protein and mRNA level of HO-1 in a concentration- and time-dependent manner in A549 cells. High glucose treatment increased production of ROS and transforming growth factor-β1 (TGF-β1) in A549 cells, which thus mediated HO-1 expression. Following the increase in HO-1 expression, the enzymatic activity of HO-1 also increased in high glucose-treated cells. Pretreatment with N-acetyl-L-cysteine (NAC) and PI3K/Akt inhibitors attenuated the high glucose-induced increased HO-1 expression. Conclusions High glucose increases ROS and TGF-β1 production in A549 cells, which mediates HO-1 expression and increases HO-1 enzymic activity.
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.
Diabetic retinopathy (DR) constitutes a major retinal vascular disorder leading to blindness in adults. Current therapeutic approaches for DR exhibit certain degrees of efficacy but are constrained by a spectrum of limitations. Hence, there is a pressing need to deeply investigate the underlying pathogenesis of DR and explore novel therapeutic targets. Ferroptosis, a distinctive form of programmed cell death, has emerged as a pertinent phenomenon in recent years. Notably, ferroptosis has been implicated in the progression of DR through mechanisms involving the induction of retinal oxidative stress, provocation of anomalous retinal vascular alterations, exacerbation of retinal neural damage, and elicitation of immune dysregulation. Thus, elucidating the mechanistic role of ferroptosis in DR holds the potential to establish a robust foundational rationale. This could potentially facilitate the clinical translation of ferroptosis inhibitors as promising agents for the prevention and treatment of DR, thereby forging novel avenues in the landscape of DR management.
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.
