Objective To investigate the effects of exosomes from cultured human retinal pigment epithelium (ARPE-19) cells affected by oxidative stress on the proliferation and expression of vascular endothelial growth factor-A (VEGF-A) and Akt of ARPE-19 cells. Methods Culture ARPE-19 cells. The concentration of 2.5 μmol/L rotenone was selected to simulate oxidative stress and isolated ARPE-19-exosome. Exosomes were isolated by ExoQuick exosome precipitation solution. Transmission electron microscopy was used to identify the morphology of exosomes. Western blot was used to detect exosomes’ surface-specific maker protein CD63. ARPE-19 cells affected by oxidative stress were cultured with exosome as experimental group, normal ARPE-19 cells were cultured with exosome as control group. The cell proliferation was examined by methyl thiazolyl tetrazolium assay. Western blot and immunofluorescence assay were used to detect the expression levels of VEGF-A and Akt protein. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the levels of VEGF-A mRNA and Akt mRNA. Results The diameter of normal ARPE-19-exosomes ranged from 50 to 150 nm. The isolated exosomes expressed CD63. AREP-19 cells were cultured with ARPE-19 (affected by rotenone)-exosome, the cell viability in experimental group was significantly reduced than in the control group. Green fluorescence was observed in the cytoplasm under fluorescence microscope. Compared with the control group, VEGF-A was up-regulated expressed and Akt was down-regulated expressed. Western blot results showed that, VEGF-A protein expression in the experimental group were higher than the control group. Akt protein expression in the experimental group were less than the control group. The difference was statically significant (t=3.822, 6.527;P＜0.05). RT-PCR results showed that VEGF-A mRNA expression levels was higher in the experimental group than the control group. Akt mRNA expression levels was lower in the experimental group than the control group. The difference was statically significant (t=8.805, ?7.823;P＜0.05). Conclusions Exosomes from ARPE-19 cells affected by oxidative stress inhibit the proliferation of normal ARPE-19 cells, increase the expression of VEGF-A and reduce the expression of Akt.
ObjectiveTo investigate the effect of diammonium glycyrrhizinate (DG) plus bone marrow mesenchymal stem cells (MSCs) transplantation in the treatment of acute exacerbation of pulmonary fibrosis induced by bleomycin (BLM) in rats.MethodsMSCs were isolated from male Wistar rats and cultured in vitro. Twenty-four female Wistar rats were randomly divided into 4 groups. The NC group was intratracheally injected with normal saline; the BLM group, the MSC group and the DGMSC group were intratracheally injected with BLM for 7 days; then the MSC group was injected with 0.5 mL of MSCs solution (2.5×106 cells) into the tail vein; the DGMSC group was intraperitoneally injected with DG for 21 days in a dose of 150 mg·kg–1·d–1 on the base of the MSCs injection. The rats were sacrificed on the 28th day and the lung tissue was extracted. Pathological examination was performed to determine the degree of alveolitis and pulmonary fibrosis. Immunofluorescence was used to detect the number and distribution of alveolar type Ⅱ epithelial cells. Alkali hydrolysis method was used to determine the content of hydroxyproline (HYP) in lung tissue; thiobarbituric acid method was used to measure the content of malondialdehyde (MDA) in lung tissue; colorimetric method was used to determine the superoxide dismutase activity (SOD) and total antioxidant capacity (T-AOC); enzyme linked immunosorbent assay was used to detect the expression levels of tumor necrosis factor-α (TNF-α ) and transforming growth factor-β1 (TGF-β1) in lung tissue homogenates.ResultsThe DG combined with MSCs injection can reduce the degree of alveolitis and pulmonary fibrosis in BLM model rats. The content of HYP and TGF-β1 in lung tissue homogenate of the DGMSC group were significantly lower than those in the MSC group (P<0.05). Meanwhile, DG combined with MSCs injection significantly increased the antioxidant capacity of the BLM model rats. MDA content decreased, SOD activity and T-AOC ability improved significantly in the DGMSC group compared with the MSC group (P<0.05). The alveolar type Ⅱ epithelial cells were significantly increased and the cell morphology was maintained in the DGMSC group compared with the MSC group.ConclusionsDG has a synergistic effect with MSCs in treatment of acute exacerbation of pulmonary fibrosis. The mechanism may be related to reducing inflammatory factors during pulmonary fibrosis, attenuating oxidative stress and promoting MSCs migration into lung tissue and transformation to alveolar type Ⅱ epithelial cells.
Abstract: Objective To determine the effects of oxidative stress reaction on intima hyperplasia after autologous vein grafting. Methods Seventy female SpragueDawley(SD) rats were randomly divided into a control group(n=10) and an experimental group (n=60). The experimental group was then divided into six time points of one day; one, two, four, and six weeks; and two months after surgery; with 10 rats for each time point. Autologous vein grafting models were established. At each time point the designated rats were anaesthetized, and the grafts were isolated and stained with HE. The same length of external jugular vein was cut from each rat in the control group. The neointima to tunica media area ratios (I/M) were measured with acomputerized digital image analysis system. Nuclear factorkappa B (NF-κB) and copper zinc superoxide dismutase (CuZnSOD) were detected byimmunohistochemistry. The concentration of malondialdehyde (MDA) in serum was analyzed by colorimetry. Results In the control group, expression levels of NF-κB and CuZnSOD were low. In the experimental group, expression of NF-κB increased after the operation and peaked two weeks later. The plateau was sustained for about one month, and then the level of expression declined gradually, reaching the baseline at the twomonth time point. The expression of CuZnSOD increased gradually after the operation and peaked one week later, then declined to the normal level after 2-3 weeks at the plateau. In the control group, the concentration of serum MDA was 4.966±1.346 nmol/ml. In the experimental -group, the-MDA concentration increased dramatically after the operation, then-declined from its highest level at the oneday time point (21.161±2.174 nmol/ml) to the normal level at two months (6.208±2.908 nmol/ml) after the operation (P＜0.05). In the control group, I/M was 0.2096±0.0253, while in the experimental group, it was higher one week after the operation (0.6806±0.0737) and peaked at four weeks (1.4527±0.0824), falling to 1.0353±00656 at six weeks and 0.9583±0.0516 attwo months (P＜0.05) for the experimental and control groups). Conclusion Endothelial cell injury initiates an oxidative stress reaction after autologous vein grafting and augments inflammation by activating NF-κB, thus playing an important role in inducing restenosis of the grafted vein.
ObjectiveTo evaluate the effects of N-acetylcysteine (NAC) on lung tissue of Wistar rats, which were tracheally instilled fine particulate matter (PM2.5).MethodsForty-eight male Wistar rats were randomly divided into six groups: two control groups [they were blank group (C1), fake treatment group (C2) separately], four treatment groups [they were PM2.5 group (P), low-dose NAC group (L), medium-dose NAC group (M), high-dose NAC group (H) separately]. C1 received no treatments at all. C2 was instilled with sterile water (1 ml/kg) tracheally once a week for four times. P was instilled equivoluminal PM2.5 suspension (7.5 mg/kg) tracheally once a week for four times. The NAC groups received gavage (10 ml/kg) of different dosage of NAC (125, 250, 500 mg/kg) for six days. At the seventh day, the NAC groups were instilled PM2.5 suspension (7.5 mg/kg) tracheally. The procedures were repeated for three times in the NAC groups. Twenty-four hours later after four weeks or after the last instilling, all rats were sacrificed. Lung tissue was stained by hematoxylin-eosin (HE) staining, and histopathological changes of lung tissue were observed by optical microscope. The levels of C-reactive protein (CRP) as well as tumor necrosis factor-α (TNF-α) of serum, TNF-α of bronchoalveolar lavage fluid (BALF), TNF-α as well as interleukin-1β (IL-1β) of homogenates of lung tissue were detected by enzyme-linked immunosorbent assay. The activity of lactate dehydrogenase (LDH) as well as the levels of malondialhyde (MDA) of serum and BALF were detected by standard colorimetric method.ResultsHE staining showed that the normal structure of lung were destroyed in the groups dealed with PM2.5 and NAC could alleviate these changes. Higher dosage of NAC seemed to provide more powerful protections. Structure of the lung in C1 as well as C2 were nearly normal. The levels of CRP as well as TNF-α of serum, TNF-α of BALF, TNF-α as well as IL-1β of homogenates of lung tissue in the groups of P, L, M, H were higher than that in the groups of C1, C2 (all P<0.05). The levels of CRP as well as TNF-α of serum, TNF-α of BALF, TNF-α as well as IL-1β of homogenates of lung tissue in the groups of L, M, H which groups received NAC treatments were lower than that in P group. More, the groups seemed to have lower levels of CRP, TNF-α, IL-1β when higher dosage of NAC were given. The activity of LDH as well as the levels of MDA of serum, and BALF in the groups of P, L, M, H were higher than that in the groups of C1, C2 (all P<0.05). The activity of LDH as well as the levels of MDA of serum and BALF in the groups of L, M, H which groups received NAC treatments were lower than that in P group (all P<0.05). ConlusionTo some extent, NAC demonstrate antagonistic effects on oxidative stress and inflammatory injury on rats’ lung brought by PM2.5.
Age-related macular degeneration (AMD) is a multifactorial disease affected by environmental factors and genetic variation, which is a major cause of irreversible vision loss in the elderly. miRNA is a kind of endogenous non-coding RNA, which plays an important role in the pathogenesis of AMD, such as oxidative stress, pathological neovascularization and inflammation, by inhibiting or silencing the expression of transcription genes. miRNA has unique advantages in terms of ease synthesis, targeting and additive effect, a large number of experiments have proved the therapeutic potential of miRNA in AMD, which is expected to become a new method for the treatment of AMD in the future. Since the pathogenesis of AMD has not been fully elucidated, it is still necessary to continue to study the pathogenesis of AMD, the biological effects and mechanisms of various miRNA in the occurrence and development of AMD, and observe its therapeutic effects in AMD, so as to provide more effective options for the precise prevention and treatment of AMD.
Objective Bone marrow mesenchymal stem cells (BMSCs) transplantation can potentially regenerate the degenerated intervertebral disc, with the underlying regenerating mechanism remaining largely unknown. To investigate the potential of human BMSCs protecting nucleus pulposus cells (NPCs) from oxidative stress-induced apoptosis in a coculturesystem, and to illustrate the possible mechanisms of BMSCs transplantation for intervertebral disc regeneration. Methods BMSCs collected by density gradient centrifugation in Percoll solution were cultured and sub-cultured till passage 3, and the surface molecules of CD34, CD45, and CD13 were identified. NPCs were isolated by collagenase digestion and the chondrocyte l ike phenotype was confirmed by morphologic observation after HE staining, inverted phase contrast microscope, proteoglycan, and collagen type II expression after toluidine blue and immunocytochemistry staining. The 3rd passage BMSCs and the 1st passage NPCs were divided into four groups: group A, NPCs (1 × 106 cells) were cultured alone without apoptosis inducing (negative control); group B, NPCs (1 × 106 cells) were co-cultured with BMSCs (1 × 106 cells) with apoptosis inducing; group C, NPCs (1 × 106 cells) were co-cultured with BMSCs (3 × 105 cells) with apoptosis inducing; group D, NPCs (1 × 106 cells) were cultured alone with apoptosis inducing (positive control). After 3 or 7 days of culture or co-culture, the NPCs in groups B, C, and D were exposed to 0.1 mmol hydrogen peroxide for 20 minutes to induce apoptosis. With DAPI staining cellular nucleus, Annexin-V/propidium iodide staining cellular membrane for flow cytometry analysis, the apoptosis of NPCs in each group was studied both qual itatively and quantitatively. Besides, the changes in Bax/Bcl-2 gene transcription and Caspase-3 protein content, were analyzed with semi-quantitative RT-PCR and Western blot. Results BMSCs were successfully isolated and CD34-, CD45-, and CD13+ were demonstrated; after isolated from degenerated intervertebral discs and sub-cultured, the spindle-shaped 1st passage NPCs maintained chondrocyte phenotype with the constructive expressions of proteoglycan and collagen type II in cytoplasm. DAPI staining showed the nucleus shrinkage of apoptosis NPCs. Co-cultured with BMSCs for 3 days and 7 days, the apoptosis rates of NPCs in groups B (29.26% ± 8.90% and 18.03% ± 2.25%) and C (37.10% ± 3.28% and 13.93% ± 1.25%) were lower than that in group D (54.90% ± 5.97% and 26.97% ± 3.10%), but higher than that of groupA (15.67% ± 1.74% and 8.87% ± 0.15%); all showing significant differences (P lt; 0.05). Besides, semi-quantitative RT-PCR showed Bcl-2 gene transcription up-regulated (P lt; 0.05) and no significant change of Bax (P gt; 0.05); Western blot result showed that the Caspase-3 protein expression of groups B and C was lower than that of group D, and was higher than that of group A; all showing significant differences (P lt; 0.05). Conclusion In a co-culture system without direct cellular interactions, the oxidative stress-induced apoptosis of human NPCs was amel iorated by BMSCs. The enhanced anti-apoptosis abil ity of NPCs preconditioned by co-culturing with BMSCs might come from the decreased Bax/Bcl-2 gene transcription ratio.
ObjectiveTo establish a cell inflammation model induced by tumor necrosis factor-α (TNF-α) in human bronchus epithelial cells, and investigate the effects of glutathione S-transferase mu 5 (GSTM5) on the inflammation and oxidative stress. Methods16HBE cells were treated with TNF-α (10 ng/mL, 24 h) in the absence or presence of the constructed GSTM5 eukaryotic expression vector (1 μg/mL). The concentration of malondialdehyde (MDA) and total antioxidation capacity (T-AOC) were detected by colorimetric method. The survival rate of cells was assessed by the methyl thiazolyl tetrazolium (MTT) assay. The transcription level of NADPH oxidase-1 (NOX1), NOX2, NOX3, NOX4, NOX5, dual oxidase-1 (DUOX1) and DUOX2 were evaluated by RT-PCR. Western blot was performed to investigate the protein levels of NOX1 and NOX2. ResultsTNF-α simulation significantly increased the level of MDA in cells, and decreased the level of T-AOC and survival rate of 16HBE. When transfected with the GSTM5 eukaryotic expression vector, the concentration of MDA significantly decreased (P < 0.05), and the activation of T-AOC increased dramatically (P < 0.05). Consequently, the survival rate of 16HBE in the GSTM5 group improved (P < 0.05). The 16HBE cells transfected with the constructed GSTM5 eukaryotic expression vector had a lower transcription and protein levels of NOX1 and NOX2 (all P < 0.01). There were no significant changes in the mRNA expressions of NOX3, NOX4, NOX5, DUOX1 or DUOX2. ConclusionGSTM5 may down-regulate the transcription level of NOX1 and NOX2 to reduce the inflammation and oxidative stress induced by TNF-α.
ObjectiveTo systematically review the association of micronucleus and polycystic ovary syndrome (PCOS).MethodsPubMed, OVID, Elsevier, CNKI, WanFang Data and CBM databases were electronically searched to collect case-control studies on the association of micronucleus and PCOS. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 5 case-control studies were included, in which 170 patients were in the case group and 148 in the control group. The results of meta-analysis showed: there were significant differences between the two groups for micronucleus frequency (MD=2.02%, 95%CI 1.63% to 2.41%, P<0.000 01) in peripheral blood lymphocytes and micro nucleated cells frequency (MD=2.43%, 95%CI 0.10% to 4.76%, P=0.04) in oral epithelial cells.ConclusionThe current evidence shows that micronucleus is associated with PCOS. Due to limited quality and quantity of the included studies, more high quality studies are needed to verify above conclusion.
Metabolic memory means if the hyperglycemia can't be controlled at early stage of diabetes, chronic complications such as diabetic retinopathy (DR) will continue to develop even if the blood glucose level maintains normal level at later stage. Oxidative stress plays an important role in the "metabolic memory" of DR, which interacts with the nitrative stress, advanced glycation end products, genetic modification and endoplasmic reticulum stress in the pathogenesis of DR. Further elucidation of the relationship between oxidative stress and "metabolic memory" of DR can open the way for the discovery of novel therapeutic targets to prevent DR progression.
ObjectiveTo investigate the protective effect of mangiferin on acute spinal cord injury (SCI) in rats and its mechanism. MethodsNinety Sprague Dawley rats were randomly divided into 5 groups, 18 rats in each group. SCI was induced by using the Allen's method (60 g/cm) at T9 level in the rats of groups B, C, D, and E; laminectomy was performed at T8-10 in group A. The rats were injected intraperitoneally with saline in groups A and B, and with mangiferin in groups C (10 mg/kg), D (25 mg/kg), and E (50 mg/kg) every day for 30 days. The survival condition of rats was observed after operation; at 24, 48, and 72 hours after operation, the motor function of the hind limb was evaluated by the Basso, Beattie, Bresnahan (BBB) scores. The spinal cord edema was assessed by measuring the water content in spinal cord tissues at 72 hours. Meanwhile, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH) were detected by ELISA; nuclear factor κB (NF-κB), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 were measured via ELISA at the same time. Caspase-3 and Caspase-9 were also detected by ELISA after mangiferin treatment for 30 days. The expressions of Bax and Bcl-2 proteins were detected by Western blot. Pathological changes of the spinal cord was observed by HE staining. And Caspase-3 protein expression was detected by immunohistochemical staining. ResultsAll rats survived to the end of experiment. BBB scores of groups B, C, D, and E were significantly less than that of group A (P < 0.05), and it showed an increase trend from groups B to E (P < 0.05). The content of water of groups B, C, D, and E were significantly greater than that of group A (P < 0.05), and it showed a decrease trend from groups B to E (P < 0.05). ELISA showed that the activities of MDA, NF-κB, TNF-α, IL-1β, IL-6, Caspase-3, and Caspase-9 in groups B, C, D, and E were significantly greater than that in group A (P < 0.05), and they showed decrease trends from groups B to E (P < 0.05). Meanwhile, the activities of CAT, SOD, and GSH in groups B, C, D, and E were significantly less than that in group A (P < 0.05), and they showed increase trends from groups B to E (P < 0.05). Western blot showed that the relative expression of Bax protein in groups B, C, D, and E were significantly greater than that in group A (P < 0.05), and it showed a decrease trend from groups B to E (P < 0.05). Meanwhile, the relative expression of Bcl-2 protein in groups B, C, D, and E were significantly less than that in group A (P < 0.05), and it showed an increase trend from groups B to E (P < 0.05). Histological observation showed that the pathological changes in group B were accord with that in SCI, and the degree of necrosis in groups C, D, and E were significantly improved when compared with that in group B, and the effect was better in group E than group D, and group D than group C. Immunohistochemical staining showed that the absorbance (A) value of Caspase-3 in groups B, C, D, and E were significantly greater than that in group A (P < 0.05), and it showed a decrease trend from groups B to E (P < 0.05). ConclusionMangiferin has neuroprotective effects on acute SCI in rats by alleviating edema of spinal cord, inhibiting oxidative stress and inflammation response, and regulating the Bcl-2 and Bax pathway.