Association of glutathione peroxidase-1 （GPx-1） rs1050450 Pro198Leu and Pro197Leu polymorphisms with cardiovascular risk：a meta-analysis of ob-servational studies

ObjectiveTo 由执行出版研究的元分析在谷胱甘肽 peroxidase-1 (GPx-1 ) 和心血管的疾病(CVD ) 的风险澄清在 rs1050450 多型性之间的协会。为 GPx-1 多型性和心血管的结果的一个协会从不同学习类型正在种证据，但是观察研究到目前为止证明了不一致的 results.MethodsRelevant 出版物通过 PubMed， Embase 数据库数据库和 Cochrane 被寻找图书馆。我们与 95% 信心间隔(CI ) 使用了机会比率(ORs ) 在最好的基因模型下面估计协会的力量。Q 统计数值和 I 2 被用来检查异质。元回归分析被执行探索异质来源。敏感分析，累积元分析分析和出版偏爱被用来测试 results.ResultsData 的可靠性从二队研究是可得到的， 8 盒子控制学习包含 1,430 个盒子和 3,767 控制。为全面 CVD 风险的分享的 ORs 与 95% CI 是 1.36：在一个 co 主导的模型下面的 1.08-1.70，并且为东方，亚洲亚群是 1.84 (95% CI：1.39-2.43 ) 。为 ORs 的实质的异质在所有包括的研究之中被检测，主要由亚洲的东方和非东方亚洲人人口之间的种族差别引起了。尽管 Egger 的回归测试没建议统计重要出版偏爱， Begg 的漏斗阴谋展出了明显的不对称现象。统计意义消失在在全面研究为潜在的出版偏爱调整以后。然而，没有实质的出版偏爱在东方亚洲 subgroup.ConclusionsGPx-1 基因 Pro198Leu 被发现， Pro197Leu 多型性更加在东方亚洲人口增加了 CVD 的风险。大规模调查被需要在不同种族证实结果。

Silent information regulator sirtuin 1 ameliorates acute liver failure via the p53/glutathione peroxidase 4/gasdermin D axis

BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple biological processes,including cellular senescence,apoptosis,sugar and lipid metabolism,oxidative stress,and inflammation.AIM To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.METHODS This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)testing.C57BL/6 mice were also intraperitoneally pretreated with SIRT1,p53,or glutathione peroxidase 4(GPX4)inducers and inhibitors and injected with lipopolysaccharide(LPS)/D-galactosamine(D-GalN)to induce ALF.Gasdermin D(GSDMD)^(-/-)mice were used as an experimental group.Histological changes in liver tissue were monitored by hematoxylin and eosin staining.ALT,AST,glutathione,reactive oxygen species,and iron levels were measured using commercial kits.Ferroptosis-and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction.SIRT1,p53,and GSDMD were assessed by immunofluorescence analysis.RESULTS Serum AST and ALT levels were elevated in patients with ALF.SIRT1,solute carrier family 7a member 11(SLC7A11),and GPX4 protein expression was decreased and acetylated p5,p53,GSDMD,and acyl-CoA synthetase long-chain family member 4(ACSL4)protein levels were elevated in human ALF liver tissue.In the p53 and ferroptosis inhibitor-treated and GSDMD^(-/-)groups,serum interleukin(IL)-1β,tumour necrosis factor alpha,IL-6,IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated.In mice with GSDMD knockout,p53 was reduced,GPX4 was increased,and ferroptotic events(depletion of SLC7A11,elevation of ACSL4,and iron accumulation)were detected.In vitro,knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels,the cytostatic rate,and GSDMD expression,restoring SLC7A11 depletion.Moreover,SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group,accompanied by reduced p53,GSDMD,and ACSL4,and increased SLC7A11 and GPX4.Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalNinduced in vitro and in vivo models.CONCLUSION SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.

硫氢化钠增加高糖高脂条件下小鼠心房肌细胞系HL-1谷胱甘肽合成

目的研究硫氢化钠(NaHS)是否通过调节谷胱甘肽(GSH)的合成,降低活性氧自由基(ROS)产生,改善小鼠2型糖尿病心肌病(DCM)。方法将小鼠心房肌细胞系HL-1分为对照组、高葡萄糖(HG:40 mmol/L)和棕榈酸(Pal:500μmol/L)处理组;以及硫氢化钠(NaHS,100μmol/L)、DL-炔丙基甘氨酸[PPG,胱硫醚γ裂解酶(CSE)抑制剂,1 mmol/L]和N-乙酰-L-半胱氨酸(NAC,ROS抑制剂,5 mmol/L)处理72 h组。Western blot检测CSE和谷胱甘肽合成酶(GSS)的表达;二氢乙锭(DHE)和二氯氟甲烷(DCFH)检测ROS含量;免疫共沉淀检测核因子红细胞系2相关因子2(Nrf2)泛素化水平及Nrf2与肌肉特异性环指蛋白1(Murf1)的相互作用。结果与对照组比高糖高脂处理HL-1细胞后CSE、溶质载体家族7成员11(SLC7A11)、谷氨酸半胱氨酸连接酶催化亚基C(GCLC)、谷氨酸半胱氨酸连接酶修饰亚基M(GCLM)、谷胱甘肽合成酶(GSS)的表达水平下降,而NaHS能恢复其表达。高糖高脂组ROS含量高于NaHS组。与NaSH组比高糖高脂条件下Murf1与Nrf2的相互作用增加,Nrf2泛素化水平明显增加。结论硫氢化钠减轻Nrf2的泛素化,增加GSH合成关键酶的表达。

Increased oxidative damage of sperm and seminal plasma in men with idiopathic infertility is higher in patients with glutathione S-transferase Mu-1 null genotype

Aim： To examine whether a relationship exists between glutathione S-transferase Mu-1 （GSTM1） gene polymorphism and the susceptibility of sperm and seminal plasma from patients with idiopathic infertility to oxidative stress. Methods： Fifty-two men with idiopathic infertility and 60 healthy fertile men were recruited to this study. GSTM1 gene polymorphism was determined by polymerase chain reaction （PCR） and both the infertile and control individuals were divided into GSTM1 null and GSTM1 positive groups according to their GSTM1 gene structure. We compared reactive oxygen species （ROS） generation, malondialdehyde （MDA）, protein carbonyls and glutathione （GSH） concentrations, and glutathione S-transferase （GST） activity in seminal plasma and spermatozoa from infertile patients and controls with respect to GSTM1 genotype. Results： Significantly higher levels of oxidative stress and damage markers were found in idiopathic infertile men with the GSTM1 null genotype compared with those with the GSTM1 positive genotype. There was no significant difference in genotype distribution for theGSTM1 variant between the idiopathic infertile subjects and fertile subjects. Patients with the GSTM1 null genotype also had lower sperm concentrations than those with GSTM1 positive genotype. Conclusion： Our results suggest that the susceptibility of sperm and seminal plasma to oxidative stress is significantly greater in idiopathic infertile men with the GSTM1 null genotype compared with those possessing the gene. Therefore, in patients with idiopathic infertility, GSTM1 polymorphism might be an important source of variation in susceptibility of spermatozoa to oxidative damage.

Glutathione S-transferase M1 polymorphism and esophagealcancer risk:An updated meta-analysis based on 37 studies

AIM: To evaluate the relationship between glutathione S-transferase M1(GSTM1) polymorphism and susceptibility to esophageal cancer(EC).METHODS: A comprehensive search of the United States National Library of Medicine Pub Med database and the Elsevier, Springer, and China National Knowledge Infrastructure databases for all relevant studies was conducted using combinations of the following terms: "glutathione S-transferase M1", "GSTM1", "polymorphism", and "EC"(until November 1, 2014). The statistical analysis was performed using the SAS software(v.9.1.3; SAS Institute, Cary, NC, United States) and the Review Manager software(v.5.0; Oxford, England); crude odds ratios(ORs) with 95% confidence intervals(CIs) were used to assess the association between the GSTM1 null genotype and the risk of EC.RESULTS: A total of 37 studies involving 2236 EC cases and 3243 controls were included in this metaanalysis. We observed that the GSTM1 null genotype was a significant risk factor for EC in most populations(OR = 1.33, 95%CI: 1.12-1.57, P_(heterogeneity) < 0.000001, and I2 = 77.0%), particularly in the Asian population(OR = 1.53, 95%CI: 1.26-1.86, P_(heterogeneity)< 0.000001, and I2 = 77.0%), but not in the Caucasian population(OR = 1.02, 95%CI: 0.87-1.19, P_(heterogeneity) = 0.97, and I2 = 0%).CONCLUSION: The GSTM1 null polymorphism may be associated with an increased risk for EC in Asian but not Caucasian populations.

Polymorphism of glutathione S-transferase mu 1 and theta 1 genes and hepatocellular carcinoma in southern Guangxi, China

AIM: Glutathione S-transferase mu 1 (GSTM1) and theta 1(GSTT1) genes are involved in the metabolism of a wide range of carcinogens, but deletions of the genes are commonly found in the population. The present study was undertaken to evaluate the association between GSTM1 and GSTT1 gene polymorphisms and hepatocellular carcinoma (HCC) risk.METHODS: The genetic polymorphisms were studied at an aflatoxin highly contaminated region in Guangxi, China.Polymerase chain reaction (PCR) technique was used to detect the presence or absence of the GSTM1 and GSTT1 genes in blood samples. The case group was composed of 181 patients of HCC identified by the pathologists and the control group was composed of 360 adults without any tumor.RFSULTS: The frequencies of GSTM1 and GSTT1 null genotypes in the control were 47.8% and 42.7%, while those in the HCC group were 64.6% and 59.7%, respectively. The differences between HCC group and control group were very significant (P＜0.01). GSTM1 and GSTT1 combined null genotypes in HCC group and control group were 38.2% and 18.5%respectively, and the difference was significant (P＜0.05).CONCLUSION: The GSTM1 and GSTT1 null genotypes are associated with an increased risk of HCC in a special geographic environment. Combination of the two null genotypes in an individual is substantially increased twice the risk of HCC.

Genetic polymorphism of glutathione S-transferase T1 gene and susceptibility to idiopathic azoospermia or oligospermia in northwestern China

Aim： To investigate the association of glutathione S-transferase T1 （GSTT1） gene polymorphism in patients with idiopathic azoospermia or oligospermia in the northwestern China population. Methods： In the case-control study, GSTT1 genotypes were identified by multiplex polymerase chain reaction （PCR） with peripheral blood DNA samples from 78 patients with idiopathic azoospermia, 103 patients with idiopathic oligospermia and 156 age-matched controls with normal sperm concentration and motility, according to the criteria adapted from World Health Organization guidelines. All of the patients and controls were from northwestern China. Results： There is a significant association between GSTT1 null genotype with idiopathic azoospermia risk （odds ratio [OR]： 2.36, 95% confidence interval [CI]： 1.33-4.20, P = 0.003） or idiopathic oligospermia risk （OR： 2.00, 95% CI： 1.17-3.27, P = 0.010）. Conclusion： GSTT1 null genotype is a predisposing risk factor for sporadic idiopathic azoospermia or oligospermia in northwestern China. （Asian J Androl 2008 Mar; 10： 266-270）

A systemic review of glutathione S-transferase P1 Ile105Val polymorphism and colorectal cancer risk

Objectives： To investigate the correlation between glutathione S-transferase P1 （GSTP1） Ilel05Val polymorphism and colorectal cancer （CRC） risk. Methods： Studies were identified to investigate the association between GSTP1 Ilel05Val polymorphism and CRC risk. Systematic computerized searches of the PubMed, Chinese National Knowledge Infrastructure, WANFANG and SinoMed were performed. Summary odds ratios （OR） and 95% confidence intervals （95 % CI） were used to measure GSTP 1 Ile 105Val polymorphisms and CRC risk. Results： A total of 23 retrospective studies were included in the meta-analysis. During all studies including 6,981 cases and 8,977 controls, sample sizes ranged from 146 to 2,144. Overall, the pooled results revealed that lie 105Val polymorphism was not associated with CRC risk and confused results were found in subgroup analyses. Further meta-analyses were conducted after excluding low-quality studies. GSTP1 Ilel05Val is associated with increased risk of CRC limited in studies with matched control. There was no significant heterogeneity in all genetic comparisons, but heterogeneity existed in subgroup analyses of heterozygous and dominant comparisons. The meta-regression analyses indicated that matched controls were the significant factor influencing between-study heterogeneity in all possible influential factors including published year, ethnicity, source of control, sample size, Hardy-Weinberg equilibrium （HWE） in control and matched controls. Sensitivity analysis revealed the pooled ORs were not changed before and after removal of each single study in all genetic comparisons, indicating the robustness of the results. Conclusions： GSTP1 Ilel05Val might be associated with increased risk of CRC. However, more high- quality case-control studies should be performed to confirm the authenticity of our conclusion.

敲低结肠癌转移相关基因1促进RSL3诱导的结直肠癌细胞铁死亡

目的探讨结肠癌转移相关基因1(MACC1)对RAS选择性致死化合物3(RSL3)诱导的结直肠癌细胞铁死亡的影响及其分子机制。方法体外培养结直肠癌细胞SW620,HCT116,LOVO及RKO细胞,Western blot实验检测细胞中MACC1表达;以SW620细胞为实验材料,MTT法检测不同浓度(0、2.5、5、10、20、40μmol/L)铁死亡诱导剂RSL3以及不同浓度(0、5、10、20μmol/L)铁死亡抑制剂Fer-1对SW620细胞存活率的影响,分析单独使用10μmol/L RLS3以及10μmol/L RLS3和10μmol/LFer-1联合作用对SW620细胞存活率的影响,并检测干扰MACC1后不同浓度RSL3对SW620细胞存活率的影响;实时定量RT-PCR和Western blot法检测不同浓度RSL3(0、2.5、5、10μmol/L)对MACC1在mRNA和蛋白水平的影响,并检测干扰MACC1后GPX4在mRNA和蛋白水平的表达;流式细胞仪及激光共聚焦实验检测干扰MACC1后,SW620细胞中脂质过氧化Lipid ROS水平的变化。结果4种结直肠癌细胞中SW620细胞MACC1表达量最高;铁死亡诱导剂RSL3抑制SW620细胞的存活率,细胞存活率随RSL3浓度升高而降低,呈剂量依赖性;不同浓度的铁死亡抑制剂Fer-1对SW620细胞的存活率没有影响;与对照Ctrl组细胞存活率相比,单独使用RSL3细胞存活率降低了50%(P<0.01),而联合使用RSL3与Fer-1处理SW620细胞,细胞的存活率得到恢复(P>0.05);不同浓度的RSL3作用于SW620细胞后,细胞中MACC1基因在mRNA和蛋白水平被显著抑制(P<0.01),具有一定的药物浓度依赖性。siRNA干扰MACC1基因表达后,增强RSL3对SW620细胞毒作用,并抑制细胞中GPX4的表达(P<0.01),增加细胞中Lipid ROS水平(P<0.05)。结论MACC1通过调控GPX4影响RSL3诱导的结直肠癌细胞铁死亡。

STUDY OF THE DELETION MUTATION OF GLUTATHIONE S TRANSFERASE M1 GENE AND ITS ROLE IN SUSCEPTIBILITYTO HEPATOCELLULAR CARCINOMA

Objection: To investigate the glutathione S transferase M1 (GSTM1) gene inherent deletion and its relation to prevalence of hepatocellular carcinoma (HCC) in Guangxi, China. Methods: The GSTM1 gene polymorphism of 120 HCC patients and 100 healthy subjects both from the same high aflatoxin B1 (AFB1) contaminated area were detected using PCR technique with special primers. Another 40 patients from AFB1 low risk area were also tested. Results: In HCC high risk area, it was found that the frequencies of GSTM1 null genotype in HCC patients and healthy subjects were 59% and 51% respectively, with no significant difference. However, the frequency of GSTM1-null genotype in control group from AFB1 low risk area was lower than those from high risk area (P<0.01). Conclusion: Populations in this HCC endemic region show a higher rate of GSTM1-null genotype, which may be partially responsible for the susceptibility to AFB1 induced HCC. But the detoxification effect of GSTM1 alone is not sufficient to resist the genetic toxicity of AFB1, especially in those people who expose to excess AFB1. The GSTM1 gene deletion would not be suitable as an independent predictor of susceptibility to HCC.

Association of glutathione S-transferase T1 and M1 gene polymorphisms with ischemic stroke risk in the Chinese Han population

Atherosclerosis plays an important role in ischemic stroke, and oxidative stress participates in the entire process of atherosclerosis. Glutathione S-transferase （GST） acting with other antioxidant enzymes can eliminate reactive oxygen species and protect cells against oxidative damage. To assess the association of glutathione S-transferase （GSTT1 and GSTM1） gene polymorphisms with ischemic stroke in the Chinese Han population, the present study selected 315 patients with ischemic stroke and 210 healthy controls for comparison. GSTT1 and GSTM1 genotypes were determined using polymerase chain reactions, electrophoresis and imaging analysis. No obvious evidence of GSTTI-nulI, GSTMI-null and GSTTI/GSTMI-double null genotype distribution differences was found between case and control groups or between genders. Subgroup analysis showed that the risk of stroke was increased when hypertension was accompanied by GSTTl-null （odds ratio （OR） = 2.996, P 〈 0.001） and GSTMl-null （OR = 3.680, P 〈 0.001 ） genotypes; diabetes mellitus was accompanied by GSTTI-null （OR = 1.860, P = 0.031） and GSTMI-null （OR = 2.444, P = 0.002） genotypes, and smokers showed a GSTTl-null genotype （OR = 2.276, P = 0.003）. GSTT1- and GSTMl-null genotypes may interact synergistically with hypertension, diabetes mellitus and smoking to increase the incidence risk of ischemic stroke.

褪黑素通过SIRT1-BMAL1通路减轻神经病理性疼痛的机制研究

目的评价褪黑素对神经病理性疼痛夜间加重的影响,并通过特异性沉默信息调节因子1(SIRT1)-脑和肌肉ARNT样蛋白1(BMAL1)通路探讨其机制。方法96只SPF级雄性C57/B6小鼠,随机分为3组:假手术(S)组、神经病理性疼痛模型(NP)组和NP模型+褪黑素治疗(NP+M)组;术前试验小鼠置于指定光照模式环境中;采用12 h光照与12 h黑暗交替环境,持续至少两周,将自然时间转换为授时时间(ZT),光照起点定为ZT0;S组小鼠仅分离坐骨神经,NP组和NP+M组采用坐骨神经慢性缩窄性损伤制备小鼠NP模型,NP+M组术后注射10 mg/kg褪黑素;Western blot法检测术后14 d各时点脊髓的SIRT1、BMAL1和谷胱甘肽过氧化酶1(Gpx1)表达量的变化;术后通过免疫荧光技术对脊髓背角SIRT1和脊髓神经元标志物神经元特异性核蛋白(NeuN)、小胶质细胞激活标记物离子钙结合适配器分子1(iba-1)、星形胶质细胞标记物胶质纤维酸性蛋白(GFAP)进行共染色,并检测各时点iba-1以确定小胶质细胞激活状态。结果与NP组ZT10时点相比,NP组小鼠术后14 d ZT22时点SIRT1、BMAL1和Gpx1降低(P<0.05);与NP组ZT14时点相比,NP+M组ZT14时点SIRT1与BMAL1升高(P<0.05),而Gpx1于ZT18时点升高(P<0.05)。SIRT1在脊髓背角与小胶质细胞共表达;与ZT10时点相比,NP组小鼠术后14 d ZT22时点小胶质细胞表达降低(P<0.05);与ZT10时点相比,NP+M组小鼠术后14 d ZT22时点小胶质细胞表达差异无统计学意义。结论褪黑素可以减轻神经病理性疼痛夜间加重,其机制可能与激活小胶质细胞SIRT1-BMAL1通路蛋白表达有关。

Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion

ATP-binding cassette（ABC） transporters ABCC1（MRP1）,ABCB1（P-gp）,and ABCG2（BCRP） contribute to chemotherapy failure.The primary goals of this study were to characterize the efficacy and mechanism of the nonsteroidal anti-inflammatory drug（NSAID）,sulindac sulfide,to reverse ABCC1 mediated resistance to chemotherapeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux.Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxorubicin and other chemotherapeutic drugs.NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines,as well as a large panel of standard tumor cell lines.Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate（GSH） transport in isolated membrane vesicles and intact cells.Selective reversal of multi-drug resistance（MDR）,decreased efflux of doxorubicin,and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID,indomethacin,in resistance selected and engineered cell lines expressing ABCC 1,but not ABCB 1 or ABCG2.Sulindac sulfide also inhibited transport of leukotriene C_4 into membrane vesicles.Sulindac sulfide enhanced the sensitivity to doxorubicin in 24 of 47 tumor cell lines,including all melanoma lines tested（7-7）.Sulindac sulfide also decreased intracellular GSH in ABCC1 expressing cells,while the glutathione synthesis inhibitor,BSO,selectively increased sensitivity to sulindac sulfide induced cytotoxicity.Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations.ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide,and in combination with chemotherapeutic drugs that induce oxidative stress.

微粒体谷胱甘肽S-转移酶1在恶性肿瘤中的研究进展

微粒体谷胱甘肽S-转移酶1(microsomal glutathione S-transferase 1,MGST1)是谷胱甘肽S-转移酶(glutathione S-transferase,GST)超家族和花生四烯酸与谷胱甘肽代谢中的膜相关蛋白(membrane-associated proteins in eicosanoid and glutathione metabolism,MAPEG)超家族的共同成员,它通过催化外源性物质的II相解毒过程,从而保护细胞膜免受氧化应激的损伤。众多研究发现MGST1与恶性肿瘤的发生发展密切相关,有望成为癌症治疗的新型分子靶点。本文就MGST1在恶性肿瘤中的研究进展予以综述。

Integrative Modeling of Oxidative Stress and C1 Metabolism Reveals Upregulation of Formaldehyde and Downregulation of Glutathione

This research provides, to the authors’ knowledge, the first integrative model of oxidative stress and C1 metabolism in plants. Increased oxidative stress can cause irreversible damage to photosynthetic components and is harmful to plants. Perturbations at the genetic level may increase oxidative stress and upregulate antioxidant systems in plants. One of the key mechanisms involved in oxidative stress regulation is the ascorbate-glutathione cycle which operates in chloroplasts as well as the mitochondria and is responsible for removal of reactive oxygen species (ROS) generated during photosynthetic operations and respiration. In this research, the complexity of molecular pathway systems of oxidative stress is modeled and then integrated with a previously developed in silico model of C1 metabolism system. This molecular systems integration provides two important results: 1) demonstration of the scalability of the CytoSolve&#174?Collaboratory&#153, a computational systems biology platform that allows for modular integration of molecular pathway models, by coupling the in silico model of oxidative stress with the in silico model of C1 metabolism, and 2) derivation of new insights on the effects of oxidative stress on C1 metabolism relative to formaldehyde (HCHO), a toxic molecule, and glutathione (GSH), an important indicator of oxidative homeostasis in living systems. Previous in silico modeling of C1 metabolism, without oxidative stress, observed complete removal of formaldehyde via formaldehyde detoxification pathway and no change in glutathione concentrations. The results from this research of integrative oxidative stress with C1 metabolism, however, demonstrate significant upregulation of formaldehyde concentrations, with concomitant downregulation and depletion of glutathione. Sensitivity analysis indicates that kGSH-HCHO, the rate constant of GSH-HCHO binding, VSHMT, the rate of formation of sarcosine from glycine, and , the rate of superoxide formation significantly affect formaldehyde homeostasis in the C1 metabolism. Future research may employ this integrative model to explore which conditions initiate oxidative stress and the resultant upregulation and downregulation of formaldehyde and glutathione.

Rethinking de novo immune hepatitis,an old concept for liver allograft rejection:relevance of glutathione S-transferase T1 mismatch

Antibody-mediated rejection(AMR) in liver transplantation has long been underestimated. The concept of the liver as an organ susceptible to AMR has emerged in recent years, not only in the context of the major histocompatibility complex with the presence of HLA donor-specific antibodies, but also with antigens regarded as "minor", whose role in AMR has been demonstrated. Among them, antibodies against glutathione S-transferase T1 have been found in 100% of patients with de novo autoimmune hepatitis(dn AIH) when studied. In its latest update, the Banff Working Group for liver allograft pathology proposed replacing the term dn AIH with plasma cell(PC)-rich rejection. Antibodies to glutathione S-transferase T1(GSTT1) in null recipients of GSTT1 positive donors have been included as a contributory but nonessential feature of the diagnosis of PC-rich rejection. Also in this update, non-organ-specific anti-nuclear or smooth muscle autoantibodies are no longer included as diagnostic criteria. Although initially found in a proportion of patients with PC-rich rejection, the presence of autoantibodies is misleading since they are not diseasespecific and appear in many different contexts as bystanders. The cellular types and proportions of the inflammatory infiltrates in diagnostic biopsies have been studied in detail very recently. PC-rich rejection biopsies present a characteristic cellular profile with a predominance of T lymphocytes and a high proportion of PCs, close to 30%, of which 16.48% are Ig G4+. New data on the relevance of GSTT1-specific T lymphocytes to PC-rich rejection will be discussed in this review.

Oxidative stress regulated heme-oxygenase-1 and glutathione S-transferase-m1 gene expression changes in cell lines exposed to melanins

To investigate the effects of oxidative stress on substantia nigra neuronal degeneration and death in patients with Parkinson＇s disease, we treated neuroblastoma cells （SK-N-SH） and glioma cells with Fenton＇s reagent, iron chelating agent, neuromelanin and dopamine melanin. We investigated the changes in expression of nine oxidative stress-related genes and proteins. The levels of mRNAs for heme-oxygenase-1 and glutathione S-transferase-ml were significantly reduced in SK-N-SH cells exposed to oxidative stress, and increased in glial cells treated with deferoxamine. These results revealed that SK-N-SH neurons react sensitively to oxidative stress, which implies different outcomes between these two types of cells in the substantia nigra. Moreover, the influences of neuromelanin and dopamine melanin on cell function are varied, and dopamine melanin is not a good model for neuromelanin.

Metformin alleviates spinal cord injury by inhibiting nerve cell ferroptosis through upregulation of heme oxygenase-1 expression

Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox homeostasis.Metformin is a classic drug used to treat type 2 diabetes that can inhibit ferroptosis.Previous studies have shown that,when used to treat cardiovascular and digestive system diseases,metformin can also upregulate heme oxygenase-1 expression.Therefore,we hypothesized that heme oxygenase-1 plays a significant role in mediating the beneficial effects of metformin on neuronal ferroptosis after spinal cord injury.To test this,we first performed a bioinformatics analysis based on the GEO database and found that heme oxygenase-1 was upregulated in the lesion of rats with spinal cord injury.Next,we confirmed this finding in a rat model of T9 spinal cord compression injury that exhibited spinal cord nerve cell ferroptosis.Continuous intraperitoneal injection of metformin for 14 days was found to both upregulate heme oxygenase-1 expression and reduce neuronal ferroptosis in rats with spinal cord injury.Subsequently,we used a lentivirus vector to knock down heme oxygenase-1 expression in the spinal cord,and found that this significantly reduced the effect of metformin on ferroptosis after spinal cord injury.Taken together,these findings suggest that metformin inhibits neuronal ferroptosis after spinal cord injury,and that this effect is partially dependent on upregulation of heme oxygenase-1.

双路通脑方调节SIRT1/Nrf2/GPx4信号通路对缺血性脑卒中大鼠神经元铁死亡的影响

目的探讨双路通脑方对缺血性脑卒中大鼠神经元铁死亡的作用以及对沉默信息调节因子2同源物1(SIRT1)/核因子E2相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPx4)信号通路的调节机制。方法采用随机数字表法选取20只大鼠作为假手术组,剩余70只大鼠均利用大脑中动脉闭塞法制备缺血性脑卒中大鼠模型,将造模成功的大鼠随机分为模型对照组、双路通脑方组、双路通脑方+SIRT1抑制剂组(双路通脑方+EX527组),每组20只。14 d后,对大鼠进行神经功能损伤评分;TTC染色检测大鼠脑梗死面积;HE染色检测大鼠脑组织病理变化;尼氏染色检测大鼠脑组织神经元数量;试剂盒检测大鼠脑组织中铁离子(Fe^(2+))、超氧化物歧化酶(SOD)、谷胱甘肽(GSH)、丙二醛(MDA)的水平;免疫组化检测大鼠脑组织中酰基-辅酶a合成酶长链家族成员4(ACSL4)、转铁蛋白受体(TFR)、铁蛋白重链多肽1(FTH1)蛋白的阳性表达;Western blotting法检测大鼠脑组织中SIRT1、Nrf2、GPx4及胱氨酸/谷氨酸转运蛋白(SLC7A11)蛋白的表达。结果与假手术组比较,模型对照组大鼠的神经功能缺损评分、脑梗死面积、Fe^(2+)和MDA含量、ACSL4、TFR蛋白表达升高(P<0.05),神经元数量、SOD和GSH含量、FTH1、SIRT1、Nrf2、GPx4及SLC7A11蛋白表达均降低(P<0.05);与模型对照组比较,双路通脑方组大鼠神经功能缺损评分、脑梗死面积、Fe^(2+)和MDA含量、ACSL4、TFR蛋白表达降低(P<0.05),神经元数量、SOD和GSH含量、FTH1、SIRT1、Nrf2、GPx4及SLC7A11蛋白表达均升高(P<0.05);采用SIRT1抑制剂进行回补实验,结果显示SIRT1抑制剂逆转了双路通脑方对神经元铁死亡的抑制作用,同时也抑制了Nrf2和GPx4的表达(P<0.05)。结论双路通脑方可能通过激活SIRT1/Nrf2/GPx4信号通路来抑制缺血性脑卒中大鼠神经元铁死亡。

T-cell allorecognition of donor glutathione S-transferase T1 in plasma cell-rich rejection

AIM To investigate the role of glutathione S-transferase T1 donor-specific T lymphocytes in plasma cell-rich rejection of liver allografts.METHODS The study group included 22 liver transplant patients. Among them, 18 patients were mismatched for the glutathione S-transferase T1(GSTT1) alleles(don+/rec-), and 4 were matched(don+/rec+). Seven of the mismatched patients produced anti-GSTT1 antibodies and developed plasma cell-rich rejection(former de novo immune hepatitis). For the detection of specific Tlymphocytes, peripheral blood mononuclear cells were collected and stored in liquid nitrogen. The memory T cell response was studied by adding to the cell cultures to a mix of 39 custom-made, 15-mer overlapping peptides, which covered the entire GSTT1 amino acid sequence. The specific cellular response to peptides was analyzed by flow cytometry using the markers CD8, CD4, IL-4 and IFNγ.RESULTS Activation of CD8^+ T cells with different peptides was observed exclusively in the group of patients with plasma-cell rich rejection(3 out of 7), with production of IL-4 and/or IFNγ at a rate of 1%-4.92% depending on the peptides. The CD4^+ response was most common and not exclusive for patients with the disease, where 5 out of 7 showed percentages of activated cells from 1.24% to 31.34%. Additionally, two patients without the disease but with the mismatch had cells that became stimulated with some peptides(1.45%-5.18%). Highly unexpected was the finding of a double positive CD4^+CD8^(low) T cell population that showed the highest degree of activation with some of the peptides in 7 patients with the mismatch, in 4 patients with plasma cell-rich rejection and in 3 patients without the disease. Unfortunately, CD4^+CD8^(low) cells represent 1% of the total number of lymphocytes, and stimulation could not be analyzed in 9 patients due to the low number of gated cells. Cells from the 4 patients included as controls did not show activation with any of the peptides. CONCLUSION Patients with GSTT1 mismatch can develop a specific T-cell response, but the potential role of this response in the pathogenesis of plasma cell-rich rejection is unknown.