Objective To study the changes of receptor activator of nuclear factor-κB ligand (RANKL, an osteoclastogenesis-promoting factor) and osteoprotegerin (OPG, the decoy receptor for RANKL), oxidative stress and bone turnover markers in obstructive sleep apnea-hypopnea syndrome (OSAHS), in order to understand the potential mechanisms underlying bone loss in OSAHS patients. Methods Ninety-eight male patients with OSAHS, confirmed by polysomnography (PSG) study, were enrolled. The patients were divided into mild-moderate groups and severe groups. Forty-two male subjects who were confirmed as not having OSAHS served as the controls. The subjects’ bone mineral density (BMD) and T-score were assessed in lumbar spine and femoral neck using dual-energy X-ray absorptiometry. Blood samples were collected from all subjects for measurement of RANKL, OPG, the bone formation marker bone-specific alkaline phosphatase (BAP), the bone resorption marker tartrate-resistant acid phosphatase-5b (TRAP-5b), total antioxidant capacity (TAOC). Twenty-eight severe OSAHS patients accepted continuous positive airway pressure (CPAP) treatment voluntarily. After 6 months, PSG was conducted, and serum RANKL, OPG, TAOC, TRAP-5b, BAP was measured after six months treatment. Results The BMD, T-score of the femoral neck and the lumbar spine were significantly lower in OSAHS patients as compared to the control group. The level of BAP was significantly decreased in the OSAHS group as compared to the control group, and there was no significant difference in TRAP-5b level between two groups. As compared with the control group, levels of OPG, TAOC and the OPG/RANKL ratio decreased significantly. None of these parameters (BMD, T-score, RANKL, OPG, TRAP-5b, BAP) showed significant difference between patients with mild-moderate and severe OSAHS group. Correlation analysis showed that the apnea hypopnea index and oxygen desaturation index were correlated with TAOC. BAP level was positively correlated with TAOC and lowest pulse oxygen saturation. The serum level of TAOC was lower in the OSAHS group after CPAP therapy, but the levels of RANKL, OPG, TRAP-5b, BAP were not different. As compared with the OSAHS group before CPAP therapy, the BMD of the femoral neck and the lumbar spine were not significant difference. Conclusions In patients with OSAHS, the oxidative stress response is enhanced, and imbalance of OPG/RANKL is shifted, which participates in the occurrence of osteoporosis. The oxidative stress injury of severe OSAHS patients was relieved after non-invasive ventilation treatment, but the effect of oxidative stress response on bone metabolism still needs further evaluation.
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.
ObjectiveTo investigate the effect of ozone on oxidative stress and energy metabolism change of blood from aortic dissection (AD) patients for providing preliminary evidence of application of ozonated autohemotherapy (ozone-AHT) in AD patients. MethodsTwenty AD patients (16 males and 4 females with a mean age of 48.51±10.21 years) were consecutively included in the First Affiliated Hospital of Harbin Medical University from March 2016 to August 2016, and blood samples were collected from all participants and ozonized in vitro at different ozone concentrations (0 μg/ml, 40 μg/ml, 60 μg/ml, 80 μg/ml, 160 μg/ml). Malondialdehyde (MDA), red blood cells (RBCs) superoxide dismutase (SOD), Na+-K+-ATP, 2,3-bisphosphoglyceric acid (2,3-DPG) at different ozone concentrations were evaluated by enzyme-linked immunosorbent assay (ELISA). ResultsIn the control group (0 μg/ml), the content of postoperative MDA was significantly higher than that of preoperation (P<0.05). The contents of postoperative SOD, Na+-K+-ATP and 2,3-DPG were significantly lower than that of preoperation (P<0.05). The content of MDA at the concentrations of 40 μg/ml, 60 μg/ml, 80 μg/ml group increased after the operation (P>0.05), and the SOD, Na+-K+-ATP, 2,3-DPG decreased compared with the preoperation (P>0.05). But all the values were not statistically significant at the concentrations of 40 μg/ml, 80 μg/ml and 160 μg/ml respectively between preoperation and postoperation (P>0.05). Compared with other concentration groups, the content of preoperative and postoperative MDA increased in the ozone group (160 μg/ml), and oppositely, the contents ofpreoperative and postoperative SOD, Na+-K+- ATP and 2,3-DPG decreased (P<0.05). Conclusion The concentrations of 40 to 80 μg/ml of ozone can improve the antioxidant capacity of erythrocyte membrane, reduce oxidative stress in blood samples of AD patients and improve the energy metabolism of erythrocyte membranes, so the concentration range of ozone is safe and feasible for the ozone-AHT of perioperative AD.
Objective To evaluate the effect of remote ischemic perconditioning on inflammation and oxidative stress in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB). Methods Sixty adult patients undergowent cardiac valve replacement under CPB. There were 29 males and 31 females with an age ranging from 40–60 years and weight from 45–70 kg. They were randomly divided into 2 groups (n=30 in each) by random number generator: a control group (group C, 14 males and 16 females) and a remote ischemic perconditioning group (group R, 15 males and 15 females). Anesthesia was induced with intravenous injection of midazolam, fentanyl, vecuronium. The patients were mechanically ventilated after endotracheal intubation. Anesthesia was maintained with intravenous injection of midazolam, fentanyl, vecuronium and inhalation of sevoflurane. Three cycles of 5-min ischemia and 5-min reperfusion were performed on the right lower extremity immediately after aortic occlusion by means of a tourniquet in group R. A tourniquet was only placed under the right lower extremity in group C. Before CPB and at 0, 1, 6 and 24 h after termination of CPB (T0-4), blood samples were obtained from the right internal jugular vein for determination of levels of serum IL-6, IL-10, SOD and MDA and the count of white blood cell and the percentage of monocytes. The bladder temperature was measured at T0-4 and SIRS score was evaluated on preoperative 1 d and postperative 1, 2 and 3 d. Tracheal extubation time and length of ICU stay were record. Results Compared with group C, the concentration of serum IL-6 at T1-3, the concentration of MDA at T1, the count of leukocyte T3, the bladder temperature at T4 and the SIRS scores on postperative 1 d were significantly decreased, while the concentration of serum IL-10 at T2-T3, the SOD activity at T1-T2, and the percentage of monocyte at T3-T4 were significantly increased in group R (P<0.05). Tracheal extubation time and length of ICU stay in group R were significantly shorter than those of group C (P<0.05). Conclusion Remote ischemic perconditioning can reduce inflammation and oxidative stress and improve post-operative recovery in patients undergoing cardiac valve replacement with CPB.
ObjectiveTo explore the protective effects of sodium valproic acid (VPA) on oxidative stress injury of osteoblasts induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and its mechanism. Methods Osteoblasts were isolated from the skulls of 10 newborn Sprague Dawley rats and cultured by tissue block method, and the 1st generation cells were identified by alkaline phosphatase (ALP) and alizarin red staining. The 3rd generation osteoblasts were cultured with 2-18 μmol/L CCCP for 2-18 minutes, and cell counting kit 8 (CCK-8) was used to detect the cell survival rate. An appropriate inhibitory concentration and culture time were selected for the preparation of osteoblasts oxidative stress injury model based on half maximal concentration principle. The cells were cultured with 0.2- 2.0 mmol/mL VPA for 12-72 hours, and CCK-8 was used to detect cell activity, and appropriate concentration was selected for further treatment. The 3rd generation cells were randomly divided into 4 groups, including blank control group (normal cultured cells), CCCP group (the cells were cultured according to the selected appropriate CCCP concentration and culture time), VPA+CCCP group (the cells were pretreated according to the appropriate VAP concentration and culture time, and then cultured with CCCP), VPA+CCCP+ML385 group (the cells were pretreated with 10 μmol/L Nrf inhibitor ML385 for 2 hours before VPA treatment, and other treatments were the same as VPA+CCCP group). After the above treatment was complete, the cells of 4 groups were taken to detect oxidative stress indicators [reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA)], cell apoptosis rate, ALP/alizarin red staining, and the relative expressions of osteogenic related proteins [bone morphogenetic protein 2 (BMP-2), RUNX2], anti-apoptotic family protein (Bcl2), apoptotic core protein (Cleaved-Caspase-3, Bax), channel protein (Nrf2) by Western blot. Results The osteoblasts were successfully extracted. According to the results of CCK-8 assay, the oxidative stress injury model was established by 10 μmol/L CCCP cultured for 10 minutes and 0.8 mmol/mL VPA cultured for 24 hours was selected for subsequent experiments. Compared with blank control group, the activity and mineralization capacity of osteoblasts in CCCP group decreased, the contents of ROS and MDA increased, the activity of SOD decreased, and the apoptosis rate increased. Meanwhile, the relative expressions of BMP-2, RUNX2, and Bcl2 decreased, and the relative expressions of Cleaved-Caspase-3, Nrf2, and Bax increased. The differences were significant (P<0.05). After further VPA treatment, the oxidative stress damage of osteoblasts in VPA+CCCP group was relieved, and the above indexes showed a recovery trend (P<0.05). In VPA+CCCP+ML385 group, the above indexes showed an opposite trend (P<0.05), and the protective effects of VPA were reversed. Conclusion VPA can inhibit the CCCP-induced oxidative stress injury of osteoblasts and promote osteogenesis via Keap1/Nrf2/Are pathway.
The aim of this research is to investigate the influence of microencapsulation on the expression of the oxidative stress genes and exogenous regulation of HepG2 cells. We compared the expression of hemeoxygenase-1 (HO-1) and glutathione S-transferases-A1 (GST-A1) in HepG2 cells under different culture conditions through real-time PCR. The effects of exogenous antioxidants on cell viability and albumin levels were also evaluated through MTT assay and ELISA assay. The results showed that after culturing for 6 and 16 days, the expression levels of HO-1 in encapsulated cells were approximately 4.9 and 3.1 times higher than that of monolayer cells at the same culture period; As for the expression levels of GST-A1, they were elevated to 11.2 and 33 times of monolayer cells (P<0.05). Accordingly, we found that NAC at 5-10 mmol/L significantly increased the viability by 40%-70% and the biosynthetic function by 20%-30% in microencapsulated HepG2 cells (P<0.05). GSH increased the viability of the encapsulated cells by 20%-55% and the biosynthetic function by 15% (P<0.05). In conclusion, oxidative stress exists in the microcapsules and affects genes expression. Exogenous antioxidants can prevent the inhibition effects of oxidative stress on cellular growth.
Objective To study the effect and mechanism of recombinant human brain natriuretic peptide (rh-BNP) in alleviating myocardial ischemia-reperfusion (I/R) injury by regulating mitogen activated protein kinase (MAPK) pathway. Methods A total of 128 adult male Sprague-Dawley (SD) rats with specific pathogen free were selected. The SD rats were divided into groups according to random number table, including, sham operation (Sham) group, I/R group, I/R+rh-BNP group, negative control adenovirus (Ad-NC)+Sham group, Ad-NC+I/R group, Ad-NC+I/R+rh-BNP group, p38 mitogen-activated protein kinase adenovirus (Ad-p38MAPK)+I/R group and Ad-p38MAPK+I/R+rh-BNP group, with 16 SD rats in each group. Myocardial I/R injury model was established by ligation of left anterior descending coronary artery. Before modeling, rh-BNP was injected intraperitoneally or adenovirus was injected into myocardium; 180 minutes after reperfusion, the contents of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB) in serum, myocardial infarction size, the contents of reactive oxygen species (ROS), tumor necrosis factor-α (TNF-α) and the expression of phosphorylated p38MAPK (p-p38MAPK), phosphorylated JNK (p-JNK) and phosphorylated extracellular regulated protein kinases 1/2 (p-ERK1/2) were detected. Results The contents of LDH, CK-MB, myocardial infarction size, the contents of TNF-α, ROS and the expression of p-p38MAPK and p-JNK in I/R group were higher than those in Sham group, p-ERK1/2 expression level was lower than that in Sham group (P<0.05). The contents of LDH, CK-MB, myocardial infarction size, the contents of TNF-α, ROS and the expression of p-p38MAPK in I/R+rh-BNP group were lower than those in I/R group (P<0.05), the expression of p-JNK and p-ERK1/2 had no significant difference compared with I/R group (P>0.05). The contents of LDH, CK-MB, myocardial infarction size, the contents of TNF-α, ROS and the expression of p-p38MAPK in Ad-p38mapk+I/R+rh-BNP group were higher than those in Ad-NC+I/R-rh-BNP group (P<0.05). Conclusion rh-BNP can alleviate myocardial I/R injury, which is related to inhibiting p38MAPK pathway, reducing inflammation response and oxidative stress response.
ObjectiveTo investigate the protective effect and mechanism of arbutin on LPS induced Acute lung injury in mice. Methods SPF BCLB/C mice were randomly divided into control group, model group,arbutin group, and arbutin+PI3K inhibitor group.arbutin group and arbutin+PI3K group were intervened with corresponding drugs respectively; Constructing an ALI model by intranasal instillation of LPS into mice; After modeling for 6 hours, the mice were killed. After staining the lung tissue slices, observe the pathological changes of the lung tissue and evaluate the lung injury score, and calculate the wet to dry weight ratio (W/D); ELISA method was used to determine the levels of TNF-a and IL-6 in serum and bronchoalveolar lavage fluid (BALF); Measure the ROS content, MDA level,and MPO activity in the lungs; Western blot method was used to detect the expression of PI3K/Akt/mTOR pathway related proteins and autophagy related proteins Beclin-1 and LC3II/I. ResultsCompared with the control group, the pathological changes in the lung tissue of model group mice worsened, and the W/D and lung injury scores increased, The levels of IL-6 and TNF-a in BALF and serum was increased, The ROS content, MDA expression and MPO activity in the lungs was increased,the expression of Beclin-1 and LC3II/I in the lungs was increased. The expression of PI3K/Akt/mTOR pathway related proteins in the lungs decreased (P<0.05). Compared with the model group, the pathological changes in the lung tissue of arbutin group mice were alleviated, with a decrease in W/D and lung injury score, The levels of IL-6 and TNF-a in BALF and serum decrease,ROS content, MDA expression and MPO activity in lung were decreased.The expression of PI3K/Akt/mTOR pathway related proteins in the lung was increased, The expression of Beclin-1 and LC3II/I decreased. However, the appeal performance was partially blocked in the arbutin+PI3K group after the administration of LY294002.ConclusionsArbutin regulates autophagy through PI3K/Akt/mTOR pathway to inhibit inflammatory response and oxidative stress in LPS-induced ALI mice, and plays a protective role in LPS-induced ALI.
Objective To investigate the effect of S-adenosyl-l-methionine (SAM) on oxidative stress and alveolar septal cell apoptosis in mice with emphysema after smoking cessation. Methods Twenty-two male SPF C57BL/6J mice aged 6 - 8 weeks were randomly divided into 4 groups, ie. a healthy control group, an emphysema group, a smoking cessation group, and a SAM intervention for 8 weeks after smoking cessation group, with 8 mice in each group. The mice model of emphysema was established by intraperitoneal injection of cigarette smoke extract (CSE) combined with cigarette smoke exposure. Smoking cessation started after the emphysema model was successfully constructed and lasted for 8 weeks. After smoking cessation, the mice in SAM intervention groups were intraperitoneally injected with SAM mg·kg–1·d–1 for 8 weeks. The right lung sections of the mice were taken for hematoxylin-eosin staining to observe pathological changes, and the mean linea rintercept (MLI) and mean alveola rnumber (MAN) of lungs were measured. The concentrations of malondialdehyde (MDA), superoxide-dismutase (SOD) and glutathione (GSH) in alveolar lavage fluid of left lung were detected by spectrophotometry. Terminal deoxynucleotidyl transferasemediated dUTP nick end labeling (TUNEL) technique was carried out to detect the alveolar septal cells apoptosis. Results MLI, apoptosis index of alveolar septal cell and MDA concentration in bronchoalveolar lavage fluid (BALF) increased significantly in the emphysema group compared with healthy controls, increased significantly in the smoking cessation group compared with the emphysema group, and decreased in the SAM intervention group compared with the smoking cessation group (all P<0.05). GSH concentration and SOD activity in BALF and MAN was significantly lower in the emphysema group compared with the healthy control group, significantly lower in the smoking cessation group compared with the emphysema group, and significantly higher in the SAM intervention group compared with the smoking cessation group (all P<0.05). Conclusions Lung histopathology and apoptosis of alveolar septal cells in emphysema mice progress continuously after smoking cessation. SAM may reduce oxidative stress and improve apoptosis of alveolar septal cells, so as to protect emphysema mice after smoking cessation.
Objective To investigate the feasibility of selenium-methylselenocysteine (SMC) to promote peripheral nerve regeneration and its mechanism of action. Methods Rat Schwann cells RSC96 cells were randomly divided into 5 groups, which were group A (without any treatment, control group), group B (adding 100 μmol/L H2O2), group C (adding 100 μmol/L H2O2+100 μmol/L SMC), group D (adding 100 μmol/L H2O2+200 μmol/L SMC), group E (adding 100 μmol/L H2O2+400 μmol/L SMC); the effect of SMC on cell proliferation was detected by MTT method, and the level of oxidative stress was detected by immunofluorescence for free radicals [reactive oxygen species (ROS)] after determining the appropriate dose group. Thirty-six 4-week-old male Sprague Dawley rats were randomly divided into 3 groups, namely, the sham operation group (Sham group), the sciatic nerve injury group (PNI group), and the SMC treatment group (SMC group), with 12 rats in each group; the rats in the PNI group were fed with food and water normally after modelling operation, and the rats in the SMC group were added 0.75 mg/kg SMC to the drinking water every day. At 4 weeks after operation, the sciatic nerves of rats in each group were sampled for neuroelectrophysiological detection of highest potential of compound muscle action potential (CMAP). The levels of inflammatory factors [interleukin 17 (IL-17), IL-6, IL-10 and oxidative stress factors catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA)] were detected by ELISA assay. The luxol fast blue (LFB) staining was used to observe the myelin density, fluorescence intensity of glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) was observed by immunofluorescence staining, and myelin morphology was observed by transmission electron microscopy with measurement of axon diameter. Western blot was used to detect the protein expressions of p38 mitogen-activated protein kinases (p38MAPK), phosphorylated p38MAPK (p-p38MAPK), heme oxygenase 1 (HO-1), and nuclear factor erythroid 2-related factor 2 (Nrf2). ResultsMTT assay showed that the addition of SMC significantly promoted the proliferation of RSC96 cells, and the low concentration could achieve an effective effect, so the treatment method of group C was selected for the subsequent experiments; ROS immunofluorescence test showed that group B showed a significant increase in the intensity of ROS fluorescence compared with that of group A, and group C showed a significant decrease in the intensity of ROS fluorescence compared with that of group B (P<0.05). Neuroelectrophysiological tests showed that the highest potential of CMAP in SMC group was significantly higher than that in PNI and Sham groups (P<0.05). ELISA assay showed that the levels of IL-6, IL-17, and MDA in PNI group were significantly higher than those in Sham group, and the levels of IL-10, SOD, and CAT were significantly lower; the levels of IL-6, IL-17, and MDA in SMC group were significantly lower than those in PNI group, and the levels of IL-10, SOD, and CAT were significantly higher (P<0.05). LFB staining and transmission electron microscopy showed that the myelin density and the diameter of axons in the SMC group were significantly higher than those of the PNI group and the Sham group (P<0.05). Immunofluorescence staining showed that the fluorescence intensity of GFAP and MBP in the SMC group were significantly stronger than those in the PNI group and Sham group (P<0.05). Western blot showed that the relative expressions of Nrf2 and HO-1 proteins in the SMC group were significantly higher than those in the PNI group and Sham group, and the ratio of p-p38MAPK/p38MAPK proteins was significantly higher in the PNI group than that in the SMC group and Sham group (P<0.05). Conclusion SMC may inhibit oxidative stress and inflammation after nerve injury by up-regulating the Nrf2/HO-1 pathway, and then inhibit the phosphorylation of p38MAPK pathway to promote the proliferation of Schwann cells, which ultimately promotes the formation of myelin sheaths and accelerates the regeneration of peripheral nerves.