Effects of low molecular weight heparin-superoxide dismutase conjugate on serum levels of nitric oxide,glutathione peroxidase,and myeloperoxidase in a gerbil model of cerebral ischemia/reperfusion injury

BACKGROUND： Several studies have demonstrated that low molecular weight heparin-superoxide dismutase （LMWH-SOD） conjugate may exhibit good neuroprotective effects on cerebral ischemia/reperfusion injury though anticoagulation, decreasing blood viscosity, having anti-inflammatory activity, and scavenging oxygen free radicals. OBJECTIVE： To investigate the intervention effects of LMWH-SOD conjugate on serum levels of nitric oxide （NO）, glutathione peroxidase （GSH-Px）, and myeloperoxidase （MPO） following cerebral ischemia/reperfusion injury. DESIGN, TIME AND SETTING： A randomized, controlled, and neurobiochemical experiment was performed at the Institute of Biochemical Pharmacy, School of Pharmaceutical Sciences, Shandong University between April and July 2004. MATERIALS： A total of 60 Mongolian gerbils of either gender were included in this study. Total cerebral ischemia/reperfusion injury was induced in 50 gerbils by occluding bilateral common carotid arteries. The remaining 10 gerbils received a sham-operation （sham-operated group）. Kits of SOD, NO, and MPO were sourced from Nanjing Jiancheng Bioengineering Institute, China. LMWH, SOD, and LMWH-SOD conjugates were provided by Institute of Biochemistry and Biotechnique, Shandong University, China. METHODS： Fifty successful gerbil models of total cerebral ischemia/reperfusion injury were evenly randomized to five groups： physiological saline, LMWH-SOD, SOD, LMWH ＋ SOD, and LMWH. At 2 minutes prior to ischemia, 0.5 mL/65 g physiological saline, 20 000 U/kg LMWH-SOD conjugate, 20 000 U/kg SOD, a mixture of SOD （20 000 U/kg） and LMWH （LMWH dose calculated according to weight ratio, LMWH： SOD = 23.6：51）, and LMWH （dose as in the LMWH ＋ SOD group） were administered through the femoral artery in each above-mentioned group, respectively. MAIN OUTCOME MEASURES： Serum levels of NO, MPO, and GSH-Px. RESULTS： Compared with 10 sham-operated gerbils, the cerebral ischemia/reperfusion injury gerbils exhibited decreased serum levels of GSH-Px and increased serum levels of NO and MPO （P 〈 0.01）. The serum level of GSH-Px was significantly upregulated in all groups, in particular in the LMWH-SOD group （P 〈 0.01）, compared with the physiological saline group （P 〈 0.05-0.01）. Following medical treatment, serum levels of NO and MPO were significantly downregulated in all groups, in particular in the LMWH-SOD group （P 〈 0.01）. Serum levels of GSH-Px, NO, and MPO in the LMWH-SOD group were close to those in the sham-operated group （P 〉 0.05）. CONCLUSION： In cerebral ischemia/reperfusion injury, LMWH-SOD conjugate exhibits stronger neuroprotective effects on free radical scavenging, inflammation inhibition, and cytotoxicity inhibition than simple or combined application of LMWH and SOD by downregulating NO and MPO levels and upregulating the GSH-Px level.

Superoxide dismutase prevents development of adenocarcinoma in a rat model of Barrett's esophagus

AIM： To test whether antioxidant treatment could prevent the progression of Barrett＇s esophagus to adenocarcinoma. METHODS： In a rat model of gastroduodenoesophageal reflux by esophagojejunal anastomosis with gastric preservation, groups of 6-10 rats were randomized to receive treatment with superoxide dismutase （SOD） or vehicle and followed up for 4 too. Rat＇s esophagus was assessed by histological analysis, superoxide anion and peroxinitrite generation, SOD levels and DNA oxidative damage. RESULTS： All rats undergoing esophagojejunostomy developed extensive esophageal mucosal ulceration and inflammation by mo 4. The process was associated with a progressive presence of intestinal metaplasia beyond the anastomotic area （9% 1st mo and 50% 4th too） （94% at the anastomotic level） and adenocarcinoma （11% 1^ST mo and 60% 4th too）. These changes were associated with superoxide anion and peroxinitrite mucosal generation, an early and significant increase of DNA oxidative damage and a significant decrease in SOD levels （P〈0.05）. Exogenous administration of SOD decreased mucosal superoxide levels, increased mucosal SOD levels and reduced the risk of developing intestinal metaplasia beyond the anastomotic area （odds ratio = 0.326; 95%CI： 0.108-0.981; P = 0.046）, and esophageal adenocarcinoma （odds ratio = 0.243; 95%CI： 0.073-0.804; P = 0.021）. CONCLUSION： Superoxide dismutase prevents the progression of esophagitis to Barrett＇s esophagus and adenocarcinoma in this rat model of gastrointestinal reflux, supporting a role of antioxidants in the chemoprevention of esophageal adenocarcinoma.

Serum manganese superoxide dismutase and thioredoxin are potential prognostic markers for hepatitis C virus-related hepatocellular carcinoma

AIM:To evaluate the clinical significance of oxidative stress markers in patients with hepatitis C virus(HCV)related hepatocellular carcinoma(HCC).METHODS:Sixty-four consecutive patients who were admitted to Kagoshima University Medical and Dental Hospital were enrolled in this retrospective study.All patients had chronic liver disease(CLD) due to infection with HCV.Thirty patients with HCV-related HCC,34 with HCV-related CLD without HCC(non-HCC),and 20 healthy volunteers(HVs) were enrolled.Possible associations between serum manganese superoxide dismutase(MnSOD) and thioredoxin(TRX) levels and clinical parameters or patient prognosis were analyzed over a mean follow-up period of 31.7 mo.RESULTS:The serum MnSOD levels were significantly higher in patients with HCV-related HCC than in patients without HCC(P = 0.03) or HVs(P < 0.001).Similarly,serum TRX levels were also significantly higher in patients with HCV-related HCC than in patients without HCC(P = 0.04) or HVs(P < 0.01).However,serum levels of MnSOD and TRX were not correlated in patients with HCC.Among patients with HCC,the overall survival rate(OSR) was lower in patients with MnSOD levels ≥ 110 ng/mL than in patients with levels < 110 ng/mL(P = 0.01),and the OSR tended to be lower in patients with TRX levels < 80 ng/mL(P = 0.05).In addition,patient prognosis with HCC was poorest with serum MnSOD levels ≥ 110 ng/mL and serum TRX levels < 80 ng/mL.Furthermore,a multivariate analysis using a Cox proportional hazard model and serum levels of five factors(MnSOD,prothrombin time,serum albumin,serum α-fetoprotein(AFP),and serum des-γ-carboxy prothrombin) revealed that MnSOD levels ≥ 110 ng/mL(risk ratio:4.12,95% confidential interval:1.22-13.88,P = 0.02) and AFP levels ≥ 40 ng/mL(risk ratio:6.75;95% confidential interval:1.70-26.85,P < 0.01) were independent risk factors associated with a poor patient prognosis.CONCLUSION:Serum MnSOD and TRX levels are potential clinical biomarkers that predict patient prognosis in HCV-related HCC.

Observation on Clinical Effect of Acupuncture on Superoxide Dismutase,Lipid Peroxide and Nitric Oxide in Vascular Dementia Patients

Objective: To observe the clinical effect of electroacupuncture and acupuncture on superoxide dismutase (SOD), lipid peroxide (LPO) and nitric oxide (NO) in vascular dementia (VaD) patients. Methods: Forty-six cases of VaD were randomly divided into two groups, the electroacupuncture group (EA group) and the acupuncture group (AP group). Assessment of Hasgawa's Dementia Scale (HDS), Functional activities Questionnaire (FAQ) and neurologic deficit scoring (NDS) were determined before and after treatment, and the changes in SOD, LPO and NO levels were observed. Results: After treatment, in the EA group, HDS of patients got elevated, FAQ lowered, SOD increased and LPO and NO decreased. The changes were significant as compared with pretreatment, P <0.01. But these parameters underwent no significant changes in the AP group after treatment. The clinical symptoms were improved in both groups, but the reduction in NDS was not significant. The total effective rate of the EA group was higher than that of the AP group. Conclusion:The immediate effect of electroacupuncture was superior to that of acupuncture, suggesting that electroacupuncture was more effective in promoting the intelligence recovery than acupuncture.

The changes of serum nitric oxide, angiotensin Ⅱ and superoxide anion in renal artery hypertension rat

Objectives To study the changes of nitric oxide, angiotensin Ⅱ and superoxide anion in renal artery hypertension pathogenesis. Methods Male Wistar rats weighing 256 -285g were divided into 5 groups randomly, 10 rats of each group. Control group: false operation was made and routine diet was given; Ligature group: left renal artery was ligatured uncompletely and routine diet was given; Ligature + Losartan group: left renal artery was ligatured uneompletely and Losartan 20mg · kg^(-1) · d^(-1) was added in the drinking water; Ligature + L -Arg group: left renal artery was ligatured uncompletely and L -Arg 2g · kg^(-1) · d^(-1) was added in the drinking water; Ligature + L - Arg + Losartan group: left renal artery was ligatured uncompletely and L - Arg 2g· kg^(-1)· d^(-1) and Losartan 20mg · kg^(-1)· d^(-1) was added in the drinking water. Blood pressure and heart rate were measured before and at the end of the experiment. One week after ligature, blood was drawn to determine angiotensin Ⅱ, cGMP, nitric oxide, nitric oxide synthase (NOS), O_2^-, superoxide dismutase (SOD). Results Systolic blood pressure was higher in ligature group than that in control group (p <0.05), systolic blood pressure was much lower in ligature + Losartan group than that in ligature group. Heart rate did not change significantly after experiment (p > 0. 05). AngⅡ was higher in ligature group than that in control group, even much higher in ligature + Losartan group (p < 0. 01 ). There was no difference of cGMP in each group (p >. 05). The concentration of NO was lower in ligature group (p <0.05), NO was higher in ligature + L - Arg + Losartan group than that in ligature group (p <0.05). O_2^- was higher in ligature group and ligature + L - Arg group than that in control group (p < 0. 05), O_2^- was lower in ligature + Losartan group than that in ligature group (p <0. 05). The level of SOD was lower in ligature group than that in control group (p <0.05), higher in ligature + L- Arg group and ligature + L - Arg + Losartan group than that in ligature group (p <0. 05). Conclusions AngⅡ,O_2^- and NO imbalance play an important role in hypertension pathogenesis, LArg and losartan may have protective effect.

Glutathione peroxidase, superoxide dismutase and catalase activities in children with chronic hepatitis

The advantages of measuring hepatic oxidative status in liver biopsy are that it helps in diagnosis of hepatic dysfunction, reflects the degree of deterioration in the liver tissues, and helps to determine the severity of hepatic injury. We aimed to study the oxidative stress state in children with chronic hepatitis by using indirect approach in which antioxidant enzymes such as glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) are determined in the liver tissue. The present study included 21 children and adolescents (12 males, 9 females) suffering from chronic hepatitis. Patients were selected from the Hepatology Clinic, New Children’s Hospital, Cairo University from November 2006 till 2009 and compared with a group of 7 children who happened to have incidental normal liver biopsy. Children with chronic hepatitis had mean age 8.12 ± 1.15 years. It was further subdivided into 2 subgroups: chronic viral heaptitis (n = 13) and cryptogenic hepatitis (n = 8). GPX, SOD and CAT levels were measured in fresh liver tissue (cell free homogenates) using ELISA. In chronic hepatitis group;there was a significant increase in the hepatic GPX activity (38.59 ± 35.82 nmol/min/ml) as compared to the control group (10.62 ± 6.68 nmol/min/ml). Also a significant correlation was observed between SOD and both ALT (r = 0.87, p < 0.05) and AST (r = 0.74, p < 0.05). GPX correlated with ALT (r = 0.80, p < 0.05) level in the chronic viral hepatitis subgroup. Our findings suggest that oxidative stress could play a role in the pathogenesis of chronic hepatitis. These preliminary results are encouraging to conduct more extensive clinical studies combining antioxidant therapy with various treatments.

Thai pigmented rice bran extracts inhibit production of superoxide, nitric oxide radicals and inducible nitric oxide synthase in cellular models

Objective:To study the inhibitory effect of rice bran extracts of Thai black Kam Muang and red Hawm Dawk Mali Deang on oxidative stress factors including superoxide(O2·-),nitric oxide(NO·),and inducible nitric oxide synthase(iNOS).Methods:Bran extracts(40%ethanol)of Kam Muang and Hawm Dawk Mali Deang were obtained and evaluated for in vitro 2-2′-azino-di-(3-ethylbenzthiazoline sulfonate)(ABTS)and NO·scavenging activity.Their inhibitory effects on cellular O2·-and NO·were measured in phorbol 12-myristate 13-acetate-stimulated neutrophil-like HL-60 cells and lipopolysaccharidestimulated RAW264.7 macrophages,respectively,and their viability was monitored using the MTT assay.The effect on iNOS expression was also assessed by the Western blotting assay.Total contents of phenolics,flavonoids,and subtypes were also determined.Results:Hawm Dawk Mali Deang exhibited about 3.5-fold greater cellular O2·-inhibitory activity than Kam Muang[EC50 values of(23.57±4.54)and(81.98±1.45)μg/mL,respectively]in phorbol 12-myristate 13-acetate-stimulated HL-60 cells.Hawm Dawk Mali Deang exhibited about 2-fold higher in vitro ABTS·+and NO·scavenging activity than Kam Muang,but it exerted cellular NO·inhibitory activity of only about 26%(undetermined EC50 value)in lipopolysaccharide-stimulated RAW264.7 cells.Conversely,Kam Muang exerted potent cellular NO·inhibitory activity[EC50 value:(281.13±59.18)μg/mL]and dose-dependently decreased iNOS levels.No cytotoxicity of both extracts was detected in both cell types.As for corresponding contents,Hawm Dawk Mali Deang contained higher contents of phenolics and flavonoids than Kam Muang.Moreover,Kam Muang and Hawm Dawk Mali Deang had a high content of total anthocyanins[(14.73±0.52)mg C3GE/g of extract]and total proanthocyanidins[(115.13±1.47)mg CE/g of extract],respectively.Conclusions:Based on these data,bran extracts of Thai black Kam Muang and red rice Hawm Dawk Mali Deang can help lower oxidative stress and inflammation attributed partly to O2·-and NO·.

Superoxide Dismutase: Therapeutic Targets in SOD Related Pathology

There are growing evidences on the role of adaptive mechanisms of all cell types in pathological processes: atherosclerosis, ischemic attack, bacterial infections, etc. All kinds of these processes involve as main mechanism oxidative stress. Aerobic organisms use oxygen in processes that accidentally or deliberately generate aggressive species for the biologic components in the form of radicals. Radicals were looked initially as “harmful” molecules and this is true for large quantities but in small or even moderate amounts these molecules prove to have a physiological role. Reactive species are highly reactive and as a consequence are short living species. Their impact is supposed to be limited in the proximity area of their formation. Instead recent evidences indicate their implications in cellular signaling suggesting that individual chemical properties of reactive species make a difference in their biological role. This paper presents superoxide, nitric oxide and peroxide radical generation under cellular changing conditions, the adapting behavior of the enzymes that synthesize and remove them as well as some therapeutic target in superoxide related pathology.

GroESL protects superoxide dismutase (SOD)— Deficient cells against oxidative stress and is a chaperone for SOD

Superoxide dismutase (SOD)-deficient Escherichia coli OX326Acells are protected against chemically-induced oxidative stress by expression of the chaperonin GroESL. This protection is equivalent to expression of superoxide dismutase even though GroESL has no inherent SOD activity. Co-overexpression of GroESL and SOD in the same cells results in higher protein yields of SOD and greater metallation of SOD when compared with expression of SOD alone. Greater metallation results in the higher specific activity of SOD that is observed in heat shock, and is not due to increased synthesis of SOD mRNA or protein.

Experience of Using the Recombinant Human Superoxide Dismutase Drug in Neurological and Ophthalmological Practice

Recsod? has been used for treating epilepsy and ophthalmological disease. Oxidative stress has been demonstrated to be a pathogenic chain of these diseases. Parameters of pro- and antioxidant systems were studied in all the patients treated. Recsod? drug was shown to produce positive effect in all the patients. Improvement of patients’ clinical condition correlated with an increase in antioxidant activities. Antioxidants, in particular, the recombinant human SOD drug, proved to be effective in treatment of some neurological and ophthalmological diseases.

Effect of Nitric Oxide on Esophageal Cancer Cell Line TE-1

Objective To investigate the radiosensitizing effect of nitric oxide(NO) combined with radiation on esophageal cancer cell line TE-1.Methods Methyl thiazolyl tetrazolium(MTT) assay was used to assess the effects of NO and radiation on TE-1 cells regarding inhibition of cell proliferation.Flow cytometry was used to examine the effect of NO and radiation on cell apoptosis and cycle.Reverse transcription polymerase chine reaction and Western blot were used to evaluete the effect of NO on mRNA and protein expression of manganese superoxide dismutase(MnSOD).Results NO inhibited the proliferation of TE-1 cells while significantly enhancing their radiosensitivity.The application of NO combined with radiation significantly increased the apoptosis rate and G2/M phase proportion of TE-1 cells,with substantial decreases in the MnSOD mRNA and protein expression levels.Conclusions NO reduces the MnSOD mRNA and protein expression levels by affecting TE-1 cell cycle,further inhibiting the apoptosis of esophageal cancer cells and enhancing the killing effect of radiation on esophageal cancer cells.

Effects of endothelial nitric oxide synthase uncoupling on pulmonary endothelial dysfunction in rats with decompression sickness

Background: To investigate the effects of unsafe decompression on rat pulmonary endothelial function and its relevant mechanisms.Methods: Sixty male Sprague-Dawley(SD) rats were randomly divided into a control group(n=30) and a decompression sickness(DCS) group(n=30). The DCS model was established by placing the rats in the DCS group in a pressurized cabin where they were exposed to a 600 k Pa compressed air environment for 60 min, and the pressure was then reduced by 100 k Pa/min until it reached atmospheric pressure. After the surviving rats in the DCS group and the rats in the control group were anesthetized, their pulmonary arteries were stripped to test the in vitro pulmonary artery endothelium-dependent vasodilation capacity. Western blotting was used to measure the expression and dissociation of endothelial nitric oxide synthase(e NOS) in pulmonary artery tissues and all protein nitration levels in pulmonary artery tissues; reactive oxygen species(ROS) formation was measured via in vitro pulmonary artery superoxide anion probe dihydroethidium(DHE) staining.Results: After experiencing unsafe decompression, 10 of the 30 rats in the DCS group died. The pulmonary artery endothelium-dependent vasodilation capacity in the surviving rats decreased significantly(P<0.05). The difference in e NOS expression between the DCS group and the control group was statistically insignificant(P>0.05), but the ratio of e NOS monomer/dimer in the DCS group was significantly higher than that in the control group(P<0.05). All protein tyrosine nitration levels in the pulmonary artery tissues of the DCS group were significantly higher than those of the control group(P<0.05). The results of DHE staining showed that the amount of ROS formation in the pulmonary arteries of the DCS group was significantly higher than that of the control group(P<0.05).Conclusion: Unsafe decompression during a simulated submarine escape process can lead to e NOS dimer uncoupling in the pulmonary artery endothelium. The dissociated e NOS monomer cannot synthesize nitric oxide(NO) and thus affect the endothelium-dependent vasodilation capacity. The e NOS monomer can promote peroxynitrite(ONOO–) synthesis, leading to an increase in protein tyrosine nitration levels in pulmonary artery tissues and causing disorder in cell cycle regulation. The e NOS monomer can also cause an increase in the formation of ROS and thus mediate peroxidation damage.

Action of Gaseous Nitric Oxide on Some Physical and Chemical Parameters of Human Blood Samples

We studied the metabolic changes induced by gaseous nitric oxide in whole blood samples in vitro. Blood samples were collected from healthy donors (Nizhny Novgorod station of blood transfusion). We carried out the direct bubbling of blood samples (n = 14) with gaseous flow with NO in a special appliance. We modeled standard conditions using the apparatus “Plazon” (concentration NO 800 mcg/l). Middle power of gas flow was used. The blood sparging time was 2 min, and exposition time lasted 3 min. Every blood sample volume was 5 ml. All the parameters were controlled before and after blood processing with NO. We tested lactate dehydrogenase activity in direct and reverse reactions spectrometrically by G. A. Kochetov’s method. Aldehyde dehydrogenase activity was examined by B. M. Kershnhots’s and E. V. Serkina’s methods, superoxide dismutase—by T. V. Sirota’s technology. Total protein level was examined by modified Louri’s method. The concentration of lactate was tested with the automatic analyzer “SuperGL Ambulance”. The indices of acidbase balance and blood gases partial pressure were estimated with special analyzer “ABL-77”. Additional control of energy metabolism changes was accomplished with derivative parameters, such as coefficient of energy reaction balance and coefficient of substrate provision. Different changes of blood physical and chemical parameters are induced by NO-processing which was fixed in our experiments. There is an inhibition of erythrocytes energy metabolism, decreasing of plasma antioxidant reserves, moderate ionic disorders and of acid-base misbalance in blood samples in vitro. Besides, according to the indirect signs, the used regimen of NO-processing mainly affected erythrocytes, and stipulated methemoglobin formation. These data testify that the used dose of gaseous nitric oxide is too high for investigated human blood. In our opinion, registered negative effects of free NO may be eliminated by bound nitric oxide use (first of all in its natural form—dinitrosyl-iron complexes).

Multiscale structural design of MnO_(2)@GO superoxide dismutase nanozyme for protection against antioxidant damage

Rational design of metallic active sites and its microenvironment is critical for constructing superoxide dismutase(SOD)nanozymes.Here,we reported a novel SOD nanozyme design,with employing graphene oxide(GO)as the framework,andδ-MnO_(2)as the active sites,to mimic the natural Mn-SOD.This MnO_(2)@GO nanozyme exhibited multiscale laminated structures with honeycomb-like morphology,providing highly specific surface area for·O_(2)−adsorption and confined spaces for subsequent catalytic reactions.Thus,the nanozyme achieved superlative SOD-like catalytic performance with inhibition rate of 95.5%,which is 222.6%and 1605.4%amplification over GO and MnO_(2)nanoparticles,respectively.Additionally,such unique hierarchical structural design endows MnO_(2)@GO with catalytic specificity,which was not present in the individual component(GO or MnO_(2)).This multiscale structural design provides new strategies for developing highly active and specific SOD nanozymes.

Cloning of a putative extracellular Cu/Zn superoxide dismutase and functional differences of superoxide dismutases in invasive and indigenous whiteflies

Superoxide dismutases （SODs） are a group of important antioxidant defense enzymes. In this study, a putative extracellular Cu/Zn superoxide dismutase （ecCuZnSOD） complementary DNA was cloned and characterized from the whitefly, Bemisia tabaci. Quantitative polymerase chain reaction analysis showed that the expression level of BtecCuZnSOD was more than 10-fold higher in the invasive Middle East Asia Minor 1 （MEAM1） than in the native Asia II 3 species of the B. tabaci species complex. After exposure to low temperature （4 ℃）, the expression of Bt-ecCuZnSOD gene was significantly up-regulated in MEAM1 but not in Asia II 3. Furthermore, the expression level ofB. tabaci intracellular CuZnSOD （Bt-icCuZnSOD）, Bt-ecCuZnSOD and mitochondrial MnSOD （Bt-mMnSOD） was compared after transferring MEAM1 and Asia II 3 whiteflies from favorable （cotton） to unfavorable host plants （tobacco）. On cotton, both CuZnSOD genes were expressed at a higher level in MEAM1 compared with Asia II 3. Interestingly, after transferring onto tobacco, the expression of Bt-ecCuZnSOD was significantly induced in Asia II 3 but not in MEAM1. On the other hand, while Bt-mMnSOD was expressed equally in both species on cotton, Bt-mMnSOD messenger RNA was up-regulated in MEAM 1 on tobacco. Consistently, enzymatic activity assays of CuZnSOD and MnSOD demonstrated that CuZnSOD might play an important protective role against oxidative stress in Asia II 3, whereas MnSOD activation was critical for MEAM1 whiteflies during host adaptation. Taken together, our results suggest that the successful invasion ofMEAM 1 is correlated with its constitutive high activity of CuZnSOD and inducible expression of MnSOD under stress conditions.

Shielding of the geomagnetic field reduces hydrogen peroxide production in human neuroblastoma cell and inhibits the activity of CuZn superoxide dismutase

Accumulative evidence has shown the adverse effects of a geomagnetic field shielded condition, so called a hypomagnetic field （HMF）, on the metabolic processes and oxidative stress in animals and cells. However, the underlying mechanism remains unclear. In this study, we evaluate the role of HMF on the regulation of cellular reactive oxygen species （ROS） in human neuroblastoma SH-SY5Y cells. We found that HMF exposure led to ROS decrease, and that restoring the decrease by additional H2O2 rescued the HMF-enhanced cell proliferation. The measurements on ROS related indexes, including total anti-oxidant capacity, H2O2 and superoxide anion levels, and superoxide dismutase （SOD） activity and expres- sion, indicated that the HMF reduced H2O2 production and inhibited the activity of CuZn-SOD. Moreover, the HMF accelerated the denaturation of CuZn-SOD as well as enhanced aggregation of CuZn-SOD protein, in vitro. Our findings indicate that CuZn-SOD is able to response to the HMF stress and suggest it a mediator of the HMF effect.

Keap1/Nrf2信号通路在非小细胞肺癌氧化应激机制中的作用

目的检测非小细胞肺癌(NSCLC)组织中Kelch样环氧氯丙烷相关蛋白-1(Keap1)、核因子E2相关因子2(Nrf2)蛋白表达水平,分析其与临床病理参数、氧化应激指标的相关性,为临床治疗提供潜在靶点。方法选取2017年4月至2020年4月郑州市第三人民医院收治的100例NSCLC患者为研究对象,免疫组化法检测并比较癌组织、癌旁组织中Keap1、Nrf2蛋白表达水平;比较不同临床病理参数患者Keap1、Nrf2蛋白表达水平;比较不同Keap1、Nrf2蛋白表达患者血清超氧化物歧化酶(SOD)、诱导型一氧化氮合酶(iNOS)、丙二醛(MDA)水平,并采用Spearman法分析SOD、i NOS、MDA与临床病理参数的相关性,采用Pearson法分析SOD、iNOS、MDA与Keap1、Nrf2蛋白水平的的相关性;比较不同Keap1、Nrf2蛋白表达患者的生存率。结果癌组织、癌旁组织Keap1蛋白阳性率分别为77.00%、53.00%,Nrf2蛋白阳性率分别为74.00%、45.00%,Keap1蛋白OD值分别为0.41±0.07、0.33±0.05,Nrf2蛋白OD值分别为0.39±0.06、0.31±0.06,癌组织Keap1、Nrf2蛋白阳性率及OD值明显高于癌旁组织,差异均有统计学意义(P<0.05);Keap1蛋白阳性表达与病理分级、T分期呈正相关(r=0.569、0.574,P<0.01),Nrf2蛋白阳性表达与病理分级、T分期呈正相关(r=0.527、0.539,P<0.01);Keap1蛋白阳性者、阴性者的血清SOD水平分别为(86.78±9.14)U/m L、(115.07±12.13)U/m L,MDA水平分别为(4.42±0.82)mmol/L、(3.24±0.56)mmol/L,i NOS水平分别为(22.74±4.31)U/m L、(15.59±3.02)U/mL,Nrf2蛋白阳性者、阴性者血清SOD水平分别为(84.94±9.12)U/mL、(117.06±12.37)U/mL,MDA水平分别为(4.48±0.85)mmol/L、(3.21±0.52)mmol/L,iNOS水平分别为(23.02±4.28)U/mL、(15.64±3.10)U/mL,Keap1、Nrf2蛋白阳性者血清SOD水平明显低于阴性者,MDA、iNOS水平明显高于阴性者,差异均有统计学意义(P<0.05);Keap1、Nrf2蛋白表达与SOD呈负相关(r=-0.612、-0.614,P<0.01),与MDA、iNOS呈正相关(r_(Keap1)=0.609、0.614,P<0.01;r_(Nrf2)=0.610、0.608,P<0.01);Keap1、Nrf2蛋白阳性表达者3年生存率为85.71%、83.78%,明显低于阴性表达者的95.65%、100.00%,差异均有统计学意义(P<0.05)。结论NSCLC组织中Keap1、Nrf2蛋白表达水平升高,且与病理分级、T分期密切相关,该信号通路活化可参与氧化应激反应过程,且对预判患者预后具有一定临床意义。

血清超氧化物歧化酶、一氧化氮、内皮素1在妊娠高血压综合征中的临床应用价值

目的探索超氧化物歧化酶(SOD)、一氧化氮(NO)、内皮素1(ET-1)在妊娠高血压综合征患者血清中的临床应用价值。方法选择2022年9月至2023年9月在中日友好医院妇产科就诊并确诊为妊娠高血压综合征的孕妇110例为妊高征组,根据高血压的分级标准分为轻度妊高征组80例和重度妊高征组30例,同时选取90名健康孕妇为对照组。使用全自动生化仪检测上述三组孕产妇的SOD、NO及常规生化及血脂指标,采用酶联免疫吸附试验检测上述两组孕产妇ET-1水平,采用SPSS19.0统计学软件对受试者的检测结果进行统计分析,进一步采用多因素logistic回归模型分析妊高征的影响因素。结果妊高征组ET-1、总胆固醇、甘油三酯、低密度脂蛋白均高于对照组,而SOD、NO、HDL低于对照组,差异有统计学意义(P<0.05);轻度妊高征组、重度妊高征组SOD、NO水平低于对照组,ET-1水平高于对照组,差异有统计学意义(P<0.05);重度高血压组血清SOD、NO水平低于轻度妊高征组,ET-1水平高于轻度妊高征组,差异有统计学意义(P<0.05);logistic回归分析结果显示:血清SOD、NO、ET-1、HDL均为孕妇发生妊高征的独立影响因素。结论SOD、NO、ET-1作为妊娠高血压疾病的血清学生物标志物具有良好的临床应用价值。

芒果苷对大鼠骨髓间充质干细胞氧化应激损伤的保护作用

背景:间充质干细胞移植治疗脊髓损伤有一定效果,但仍存在局部氧化应激环境导致移植细胞存活率低、细胞移植效率不佳等问题。目的:探究芒果苷在氧化应激状态下对骨髓间充质干细胞的保护作用。方法:取第3代大鼠骨髓间充质干细胞,按浓度梯度0,20,40,80,160μmol/L加入芒果苷孵育2 h,然后加入含400μmol/L H_(2)O_(2)的无血清L-DMEM培养基及相应浓度的芒果苷继续培养12 h及24 h,以常规培养的大鼠骨髓间充质干细胞为正常对照组。MTT法检测各组细胞存活情况,按照试剂盒操作方法检测细胞培养液中超氧化物歧化酶、丙二醛及过氧化氢酶水平。结果与结论:与正常对照组相比,H_(2)O_(2)组细胞的存活能力显著降低(P<0.01),超氧化物歧化酶、过氧化氢酶水平显著降低(P<0.01),丙二醛水平显著升高(P<0.01);与H_(2)O_(2)组相比,芒果苷组细胞的存活能力显著升高(P<0.01),超氧化物歧化酶、过氧化氢酶水平显著升高(P<0.01),丙二醛水平显著降低(P<0.01)。芒果苷在20μmol/L浓度以上表现出浓度依赖性的抗氧化应激保护活性,且在160μmol/L以下无细胞毒性。结果表明,抗氧化剂芒果苷可增加骨髓间充质干细胞的抗氧化活性,为骨髓间充质干细胞移植提供一种新的预处理策略。

NRF2 signaling cascade in amyotrophic lateral sclerosis:bridging the gap between promise and reality

Amyotrophic lateral sclerosis is a very disabling disease due to the degeneration of motor neurons.Symptoms include muscle weakness and atrophy,spasticity,and progressive paralysis.Currently,there is no treatment to reverse damage to motor neurons and cure amyotrophic lateral sclerosis.The only two treatments actually approved,riluzole and edaravone,have shown mitigated beneficial effects.The difficulty to find a cure lies in the complexity and multifaceted pattern of amyotrophic lateral sclerosis pathogenesis.Among mechanisms,abnormal RNA metabolism,nucleocytoplasmic transport defects,accumulation of unfolded protein,and mitochondrial dysfunction would in fine induce oxidative damage and vice versa.A potent therapeutic strategy will be to find molecules that break this vicious circle.Sharpening the nuclear factor erythroid-2 related factor 2 signaling may fulfill this objective since nuclear factor erythroid-2 related factor 2 has a multitarget profile controlling antioxidant defense,mitochondrial functioning,and inflammation.We here discuss the interest of developing nuclear factor erythroid-2 related factor 2-based therapy in regard to the pathophysiological mechanisms and we provide a general overview of the attempted clinical assays in amyotrophic lateral sclerosis.