ObjectiveTo investigate the effect of nicotinamide mononucleotide adenosyl transferase 3 (NMNAT3) on the mitochondrial function and anti-oxidative stress of rabbit bone marrow mesenchymal stem cells (BMSCs) under oxidative stress in vitro by regulating nicotinamide adenine dinucleotide (NAD+) levels.MethodsThe bone marrow of femur and tibia of New Zealand white rabbits were extracted. BMSCs were isolated and cultured in vitro by density gradient centrifugation combined with adherent culture. The third generation cells were identified by flow cytometry and multi-directional induction. Overexpression of NMNAT3 gene was transfected into rabbit BMSCs by enhanced green fluorescent protein (EGFP) labeled lentivirus (BMSCs/Lv-NMNAT3-EGFP), and then the expression of NMNAT3 was detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot and cell proliferation by cell counting kit 8 (CCK-8) method. BMSCs transfected with negative lentivirus (BMSCs/Lv-EGFP) and untransfected BMSCs were used as controls. The oxidative stress injury cell model was established by using H2O2 to treat rabbit BMSCs. According to the experimental treatment conditions, they were divided into 4 groups: Group A was normal BMSCs without H2O2 treatment; untransfected BMSCs, BMSCs/Lv-EGFP, and BMSCs/Lv-NMNAT3-EGFP in groups B, C, and D were treated with H2O2 simulated oxidative stress, respectively. The effects of NMNAT3 on the mitochondrial function of BMSCs under oxidative stress [changes of mitochondrial membrane potential, NAD+ and adenosine triphosphate (ATP) levels], the changes of anti-oxidative stress ability of BMSCs [reactive oxygen species (ROS) and malondialdehyde (MDA) levels, manganese superoxide dismutase (Mn-SOD) and catalase (CAT) activities], and the effects of BMSCs on senescence and apoptosis [senescence associated-β-galactosidase (SA-β-gal) staining and TUNEL staining] were detected after 24 hours of treatment.ResultsThe rabbit BMSCs were successfully isolated and cultured in vitro. The stable strain of rabbit BMSCs with high expression of NMNAT3 gene was successfully obtained by lentiviral transfection, and the expressions of NMNAT3 gene and protein significantly increased (P<0.05). There was no significant difference in the trend of cell proliferation compared with normal BMSCs. After treatment with H2O2, the function of mitochondria was damaged and apoptosis increased in all groups. However, compared with groups B and C, the group D showed that the mitochondrial function of BMSCs improved, the membrane potential increased, the level of NAD+ and ATP synthesis of mitochondria increased; the anti-oxidative stress ability of BMSCs enhanced, the levels of ROS and MDA decreased, and the activities of antioxidant enzymes (Mn-SOD, CAT) increased; and the proportion of SA-β-gal positive cells and the rate of apoptosis decreased. The differences in all indicators between group D and groups B and C were significant (P<0.05).ConclusionNMNAT3 can effectively improve the mitochondrial function of rabbit BMSCs via increasing the NAD+ levels, and enhance its anti-oxidative stress and improve the survival of BMSCs under oxidative stress conditions.
【摘要】 目的 观察长期大量酒精摄入对大鼠心肌结构及心肌组织中丙二醛(MDA)、超氧化物歧化酶(SOD)和金属硫蛋白(MT)含量的影响,探讨氧化应激在酒精性心肌病大鼠中的作用。 方法 雄性健康SD大鼠45只,随机分为2组,即对照组20只和模型组25只。模型组酒精浓度从5%、10%、20%和30%依次各自由饮1周,然后递增至36%后以该浓度维持饲喂。对照组每日饮用与模型组酒精同等热量的葡萄糖水。6个月后,观察大鼠心肌组织的形态学改变及超微结构的变化,测定心肌组织中MDA、SOD及MT的含量。结果 模型组大鼠心肌细胞排列紊乱、间质充血、炎细胞浸润、线粒体肿胀、空泡形成、肌丝溶解、核膜不规则和核仁裂解。心肌组织中MDA含量明显升高(Plt;0.01),SOD活力含量明显降低(Plt;0.01),MT含量明显降低(Plt;0.01)。 结论 长期摄入大量酒精可使氧自由基代谢失衡,导致心肌损伤。氧化应激在酒精性心肌病发病机制中发挥着重要的作用。【Abstract】 Objective To observe the effect of longterm and large quantities of alcohol intake on myocardial structure of rats and the content of malondialdehyde (MDA), superoxide dismutase (SOD) and metallothionein (MT) in myocardium tissue. To study the effect of oxidative stress on the rats with alcoholic cardiomyopathy. Methods Fortyfive male and healthy SD rats were randomly divided into the control group (20 rats) and model group (25 rats).The alcoholic concentrate in model group was increased from 5%,10%,20% to 30% every week, and maintain free drinking mass concentration of 36% alcohol. The control group drink the same calories of glucose water. Six months later, the myocardial tissues were observed both in light microscope and electron microscope .The level of MDA、SOD and MT were tested in myocardium tissue. Results In the model rats, the cells of myocardial disarray, interstitial congestion, inflammatory cell infiltration, mitochondrial swelling, vacuole formation, melt filaments, irregular nuclear membrane and nucleolus cracking. The content of MDA incresed(Plt;0.01)and the activities of SOD decreased(Plt;001),levels of MT decreased (Plt;0.01) in the cardiac muscular tissues in the model group compared with the control group. Conclusion Longterm intake of large amounts of alcohol can break the balance of oxygen free radicals, which leading to the damage of myocardial. Oxidative stress plays an important role in the etiopathogenesis of alcoholic cardiomyopathy.
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.
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.
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.
ObjectiveTo study the effects of the new small molecular oxygen free radical scavenger Tempol on the survival and vasculogenesis of the long random pattern skin flap (LRPSF) and its mechanism. MethodsEighty-four male Sprague Dawley rats were randomly divided into control and Tempol groups (42 rats in each group). LRPSF of 9 cm×3 cm in size were prepared on the backs of rats in two groups based on the Mcfarlane flap. Rats were administered with Tempol (100 mg/kg) in the Tempol group and with normal saline in the control group by intraperitoneal injection at 15 minutes before operation and at 1-7 day after operation. The rat and the skin flap survival conditions were observed after operation; the survival rate of skin flap was measured, and the vascular structure, vascular volume, and total length of blood vessels were analyzed with Micro-CT three-dimensional imaging after 7 days; HE staining was used to observe the structure of the skin flaps and inflammation, immumohistochemical staining to observe vascular endothelial growth factor (VEGF) expression; water-soluble tetrazolium-1 method was used to measure the content of superoxide dismutase (SOD) and malondialdehyde (MDA), and ELISA to detect the expressions of tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) after 1, 3, and 7 days. ResultsAll of rats survived after operation, without hemorrhage, edema, and infection. With the extension of time, necrosis occurred in the distal part of the skin flaps in 2 groups, but the necrosis degree of the Tempol group was lower than that of control group; meanwhile, the blood vessel distribution and continuity were better than those of control group. The skin flaps survival rate, vascular volume, and total length of blood vessels of Tempol group were significantly higher than those of control group after 7 days (P<0.05). The clearer skin flaps structure, lighter inflammation reaction and inflammation cell infiltration, and higher VEGF staining intensity were observed in the Tempol group than the control group after 7 days. There was no significant difference in SOD, MDA, and TNF-α, and IL-6 contents between the 2 groups at immediate after operation. SOD significantly increased, but MDA, TNF-α, and IL-6 contents significantly decreased in the Tempol group when compared with control group after 1, 3, and 7 days (P<0.05). ConclusionTempol can significantly promote the LRPSF survival rates, its mechanism is closely related to the promotion of vasculogenesis and reduction of oxidative stress and inflammation.
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.
ObjectiveTo study the effect of rotenone on rat substantia nigra dopamine (DA) in the nervous system and oxidative stress parameters (malondialdehyde and glutathione), the influence of rotenone on DA neurons toxic effect and its pathogenesis. MethodsThis study applied back subcutaneous injection of rotenone in rats [1.0 mg/(kg·d)], and used immunocytochemistry technique to detect changes in the expression of tyrosine kinase (TH) in 10 rats of the control group and 10 rats of the experimental group. Spectrophotometry was used to detect the change of oxidative stress parameters in rats (malondialdehyde and glutathione). ResultsDA neurons in rats had various degrees of damage. The TH immune response strength of rats in the substantia nigra and striatum decreased significantly. The number of immune response nigra TH positive neurons was significantly less in the experimental group than in the control group (P< 0.01). Spectrophotometer method was used to detect the midbrain nigra of glutathione, which was significantly less in the experimental group than in the control group (P<0.01). Malondialdehyde in the experimental group was significantly higher (P<0.01). ConclusionRotenone has obvious neurotoxicity, and can lead to the damage of DA neurons and obvious oxidative stress injury in rats, which provides an experimental basis for the pathogenesis of Parkinson's disease, and at the same time provides new targets for the treatment.
目的 研究同型半胱氨酸转硫途径、维生素B6及内源性硫化氢在慢性阻塞性肺疾病急性加重期（AECOPD）中的作用。 方法 2010年2月－4月间筛选AECOPD患者16例和健康志愿者（对照组）13例，测定AECOPD患者加重期、缓解期及对照组的肺功能、血清硫化氢（H2S）、丙二醛（MDA）、叶酸、维生素B12、C反应蛋白、白介素6、血浆同型半胱氨酸、胱硫醚、半胱氨酸和维生素B6的浓度。计算半胱氨酸转化率（半胱氨酸浓度/胱硫醚浓度）与胱硫醚转化率（胱硫醚浓度/同型半胱氨酸浓度）参与分析。 结果 ① 加重期血清MDA水平[（7.3 ± 5.1）nmol/L ]比缓解期[（3.0 ± 1.4）nmol/L ]和对照组[（3.0 ± 2.2）nmol/L ]均升高（P＜0.01）；血清MDA水平与第1秒用力呼气容积/用力肺活量（FEV1/FVC）、第1秒用力呼气容积占预计值百分比（FEV1%预计值）呈负相关。② 加重期血清H2S水平与血浆维生素B6水平较缓解期与对照组降低（P＜0.01）；缓解期血清H2S水平[（47.2 ±5.1） μmol/L ]高于对照组[（38.8 ± 2.1） μmol/L ]，P＜0.01；血清H2S水平、血浆维生素B6水平均与FEV1%预计值呈正相关（r=0.651、0.680，P＜0.01），均与血清MDA水平呈负相关（r=-0.334、-0.448，P＜0.05）。③ 加重期半胱氨酸转化率（3.97 ± 2.41）低于缓解期（5.92 ± 2.18）与对照组（6.14 ± 3.15）差异有统计学意义（P＜0.05）；而胱硫醚转化率则相反。④ 叶酸与维生素B12水平各组间均无差异。 结论 提高AECOPD患者维生素B6及H2S浓度可能能促使AECOPD患者向稳定状态转归，减轻氧化应激损伤。维生素B6与H2S可能成为AECOPD患者的一个新的治疗点。Objective To study the roles of homocysteine (Hcy) transsulfuration pathway, Vitamin B6 and endogenous hydrogen sulfide in treating patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods Sixteen AECOPD patients and 13 healthy controls (Control group) from February to April 2010 were recruited in this study. Lung function, serum hydrogen sulfide (H2S), malondialdehyde (MDA), folate, vitamin B12, C-reactive protein (CRP), interleukin-6 (IL-6), Hcy, cystathionine, cystein (Cys) and vitamin B6 were all measured for all the patients in the acute exacerbation period and alleviation period and healthy controls. The conversion rate of Cys (expressed as Cys/cystathionine) and the conversion rate of cystathionine (expressed as cystathionine/Hcy) were calculated for analysis. Results Serum MDA level for patients in the acute exacerbation period (AE period) [(7.3 ± 5.1) nmol/L] was significantly higher than that in the alleviation period [(3.0 ± 1.4) nmol/L] and in the healthy controls [(3.0 ± 2.2) nmol/L] (P ＜ 0.01). Serum MDA level was negatively correlated with percentage of FEV1 in predicted FEV1 (FEV1% pred) and FEV1/FVC. Serum H2S level and plasma vitamin B6 level for patients in the AE period were significantly lower than those in the alleviation period and in the healthy controls (P ＜ 0.01), and serum H2S level was significantly higher in the alleviation period [(47.2 ± 5.1) μmol/L] than in the controls [(38.8 ± 2.1) μmol/L] (P ＜ 0.01). Both serum H2S and plasma vitamin B6 levels were correlated positively with FEV1% pred for patients in the AE period and healthy controls (r=0.651, 0.680; P ＜ 0.01), but negatively correlated with serum MDA level (r=-0.334, -0.448; P ＜ 0.05). The conversion rate of Cys for patients in the AE period (3.97 ± 2.41) was significantly lower than that in the alleviation period (5.92 ± 2.18) and the control group (6.14 ± 3.15) (P ＜ 0.05), but the conversion rate of cystathionine was just the opposite (P ＜ 0.05). There were no significant differences in the levels of serum folate and vitamin B12 among the three groups. Conclusion Raising the Vitamin B6 and H2S level may facilitate stabilizing of conditions in patients with AECOPD and reduce oxidative stress. Therefore, it may become a new treatment method for AECOPD.