Activation of Nrf2/HO-1/NQO1 Signaling Pathway by Shenqi Tangluo Pill Improves Oxidative Stress Injury of Skeletal Muscle of Type 2 Diabetes Mellitus Mice / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of Shenqi Tangluo pill （SQTLP） on oxidative stress injury of skeletal muscle of type 2 diabetes mellitus （T2DM） mice based on nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1）/NAD（P）H quinone oxidoreductase 1 （NQO1） pathway. MethodA total of 60 7-week-old male db/db mice ［specific pathogen-free （SPF） grade］ were selected and fed for one week for adaption. They were divided into the model control group， SQTLP low-， medium- and high-dose （19， 38， and 76 g·kg-1） groups and metformin group （0.26 g·kg-1） by gavage. Each group consisted of 12 mice. Twelve male db/m mice of the same age were selected as the blank group. The intervention was implemented continuously for 8 weeks. Fasting blood glucose （FBG） was detected. Fasting serum insulin （FINS） levels were detected by enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment-insulin resistance （HOMA-IR） index and the homeostasis model assessment-insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） and the contents of malondialdehyde （MDA） and reduced nicotinamide adenine dinucleotide phosphate （NADPH） in skeletal muscle tissues were detected by biochemical kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in skeletal muscle tissues. The levels of reactive oxygen species （ROS） and 4-hydroxynonenal （4-HNE） in skeletal muscle tissue were detected by immunofluorescence （IF）. The expression levels of Nrf2， HO-1， NQO1 and glutamate-cysteine ligase catalytic subunit （GCLC） proteins in skeletal muscle tissues were detected by Western blot. ResultCompared with those in the blank group， FBG， FINS and HOMA-IR in the model group were significantly increased （P<0.05）， while HOMA-ISI was decreased （P<0.05）. The results of OGTT and ITT showed that blood glucose was significantly increased at all time points （P<0.05）， and glucose tolerance and insulin tolerance were significantly impaired. SOD and GSH-Px activities in skeletal muscle tissues were significantly decreased （P<0.05）， and MDA and NADPH contents were significantly increased （P<0.05）. In skeletal muscle tissues， the arrangement of muscle fibers was loose， the nucleus was disordered， and inflammatory cells were infiltrated. The expression levels of ROS and 4-HNE in skeletal muscle tissues were significantly increased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly decreased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the metformin group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that blood glucose in the metformin group was significantly decreased at all time points （P<0.05）. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue of the metformin group. The expressions of ROS and 4-HNE in skeletal muscle tissues were decreased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly increased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the SQTLP medium- and high-dose groups were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the glucose tolerance and insulin tolerance of mice were improved in each dose group of SQTLP. The GSH-Px activity in the SQTLP low-dose group was significantly increased （P<0.05）， and the NADPH content was decreased （P<0.05）. The activities of SOD and GSH-Px in the SQTLP medium- and high-dose groups were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. The skeletal muscle tissue injury of mice in each dose group of SQTLP was ameliorated to different degrees. In the SQTLP medium- and high-dose groups， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05）. Compared with those in the SQTLP low-dose group， FBG and HOMA-IR in the SQTLP high-dose group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the SQTLP high-dose group significantly improved the glucose tolerance and insulin tolerance of mice. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05） in the skeletal muscle tissue of the SQTLP high-dose group. ConclusionSQTLP can significantly improve IR in T2DM mice， and the mechanism is related to SQTLP activating the Nrf2/HO-1/NQO1 signaling pathway， promoting the expression of antioxidant enzymes， and thus improving the oxidative stress injury in the skeletal muscle.

Research progress on the relationship between diquat poisoning and nuclear factor E2-related factor 2 signaling pathway / 中华危重病急救医学

Since the production and use of paraquat was banned in China in 2016, the use of diquat (DQ) has been increasing and the clinical cases of DQ poisoning have also shown an increasing trend every year. The treatment of DQ poisoning is a worldwide medical problem, and there is no specific antidote. Studies have found that oxidative stress, lipid peroxidation, neurotoxicity, reproductive and developmental toxicity play an important role in DQ poisoning. Nuclear factor E2-related factor 2 (Nrf2) can inhibit oxidative stress, lipid peroxidation and inflammation by regulating the protein expression of upstream and downstream signaling molecules. Therefore, the role of Nrf2 signaling pathway in the poisoning and treatment of DQ has become a hot spot of attention for emergency critical care researchers in recent years. This paper reviews the relationship between Nrf2 signal pathway and DQ poisoning, in order to provide a theoretical basis for improving the treatment strategy for DQ poisoning.

Expression and role of anti-oxidative damage factors in the placenta of preterm infants with premature rupture of membranes / 中国当代儿科杂志

OBJECTIVES@#To study the association of the anti-oxidative damage factors nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H:quinone oxidoreductase-1 (NQO1) with preterm premature rupture of membranes (PPROM).@*METHODS@#A prospective study was conducted. The neonates who were hospitalized in Yanbian Hospital from 2019 to 2020 were enrolled as subjects, among whom there were 30 infants with PPROM, 32 infants with term premature rupture of membranes (TPROM), and 35 full-term infants without premature rupture of membranes (PROM). Hematoxylin and eosin staining was used to observe the inflammatory changes of placental tissue. Immunohistochemical staining was used to measure the expression of Nrf2, HO-1, and NQO1 in placental tissue. Western blot was used to measure the protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue.@*RESULTS@#Compared with the PPROM group, the TPROM group and the non-PROM full-term group had significantly higher positive expression rates and relative protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue (P<0.05). There were no significant differences in the positive expression rates and relative protein expression levels of Nrf2, HO-1, and NQO1 in placental tissue between the TPROM and non-PROM full-term groups (P>0.05).@*CONCLUSIONS@#The low expression levels of Nrf2, HO-1, and NQO1 in placental tissue may be associated with PPROM, suggesting that anti-oxidative damage is one of the directions to prevent PPROM.

Effect and Mechanism of Banxia Xiexintang on Rats with Chronic Atrophic Gastritis Based on Keap1/Nrf2/ARE Signaling Pathway / 中国实验方剂学杂志

Objective:To explore the mechanism of Banxia Xiexintang （BXXX） in preventing and treating chronic atrophic gastritis （CAG） through Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor erythroid 2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway. Method:SD rats were divided into a normal group （<italic>n</italic>=12） and an experimental group for CAG model induction. The model rats were then randomly divided into a model group， a vatacoenayme （VG） group （60 mg·kg^-1）， and high- （280 mg·kg^-1）， medium- （140 mg·kg^-1）， and low-dose （70 mg·kg^-1） BXXX groups. The doses in the BXXX groups were equivalent to 28， 14， and 7 g·kg^-1 crude drugs. The rats in the normal group and the model group received distilled water at an equal volume， and those in the VG group and the BXXX groups were treated correspondingly by gavage. After 12 weeks of treatment， hematoxylin-eosin （HE） staining was carried out to observe pathological changes in the gastric mucosa of CAG rats. Western blot and real-time fluorescence-based quantitative PCR was used to detect the protein and mRNA expression levels of Nrf2， glutathione S-transferase （GST）， and NAD （P）H：quinone oxidoreductase 1 （NQO1） in the gastric mucosa of CAG rats. Result:Compared with the normal group， the model group showed increased protein and mRNA expression levels of Nrf2， NQO1， and GST in the gastric mucosa of the rats （<italic>P</italic><0.05）， atrophic gastric mucosa， and even intestinal metaplasia. The protein and mRNA expression levels of Nrf2， NQO1， and GST in the VG group and the high- and medium-dose BXXX groups were lower than those in the model group （<italic>P</italic><0.05）， and gastric mucosa atrophy and intestinal metaplasia were significantly improved， especially in the high-dose BXXX group. However， the effect in the low-dose BXXX group was not significant. Conclusion:BXXX can blunt the transcriptional activity of Nrf2， shut down Nrf2 signaling pathway， and reduce the expression levels of NQO1 and GST to achieve normal oxidation-anti-oxidation balance， which may be one of its action mechanisms in the treatment of CAG.

Naringenin increases Nrf2/phase II detoxifying enzymes to reduce vascular inflammation / 中国药理学通报

Aim To investigate the role of naringenin in nuclear factor erythroid 2-related factor 2 (Nrf2)/ phase II detoxifying enzyme activities and evaluate its effects on vascular inflammation. Methods Western blot, immunofluorescence and reverse transcription- qPCR were used to detect the protein expression. The activities of phase II detoxifying enzymes were measured by commercial kits. Immunoprecipitation technology was used to detect the interaction between Nrf2 and kelch-like ECH-associated protein 1 ( Keap-1). Results Naringenin promoted the dislocation of Nr£2 from Keap-1 and increased Nrf2 nuclear accumulation in RAW264. 7 macrophages. Naringenin up-regulated expressions of phase II detoxifying enzymes such as NAD(P)H quinone oxidoreductase ( NQO-1), gluta thione S-transferase (GST) and glutamate-cysteine lig- ase (GCL). It also reduced the levels of cytokines in macrophages. Moreover, the Nrf2 inhibitor ML385 reduced phase II detoxifying enzyme expressions and increased cytokine levels. In addition, we found naringenin increased the expressions and activities of liver phase II detoxifying enzymes ( NQO-1, GST and GCL) and reduced aortic inflammation in atherosclerotic model mice. The effects were dependent on Nr£2 activity. Conclusions Naringenin activates Nrf2 and promotes phase II detoxifying enzyme activities, which leads to the inhibition of vascular inflammation.

A new quinone and a new phenolic glycoside from Thymus quinquecostatus / 中草药

Objective: To study the chemical components of Thymus quinquecostatus in order to find new compounds. Methods: The constituents were separated by column chromatographic methods of silica gel, AB-8 resin, Sephadex LH-20 and ODS column. The structures were elucidated by MS and NMR analyses. Results: Two compounds were isolated and identified as 6-hydroxy-11-methyl-12-hydroxymethyl naphtho [2,3-β] furan-1,4-dione (1) and 2-hydroxy-4-isopropyl-5-methylbenzene-O-β-D- glucopyranoside (2). Conclusion: Compounds 1 and 2 are new compounds, named quinquequinone A and quinqueside A, respectively.

Synthesis of pyrroloquinoline quinone by recombinant Gluconobacter oxydans / 生物工程学报

Pyrroloquinoline quinone (PQQ), an important redox enzyme cofactor, has many physiological and biochemical functions, and is widely used in food, medicine, health and agriculture industry. In this study, PQQ production by recombinant Gluconobacter oxydans was investigated. First, to reduce the by-product of acetic acid, the recombinant strain G. oxydans T1 was constructed, in which the pyruvate decarboxylase (GOX1081) was knocked out. Then the pqqABCDE gene cluster and tldD gene were fused under the control of endogenous constitutive promoter P0169, to generate the recombinant strain G. oxydans T2. Finally, the medium composition and fermentation conditions were optimized. The biomass of G. oxydans T1 and G. oxydans T2 were increased by 43.02% and 38.76% respectively, and the PQQ production was 4.82 and 20.5 times higher than that of the wild strain, respectively. Furthermore, the carbon sources and culture conditions of G. oxydans T2 were optimized, resulting in a final PQQ yield of (51.32±0.899 7 mg/L), 345.6 times higher than that of the wild strain. In all, the biomass of G. oxydans and the yield of PQQ can be effectively increased by genetic engineering.

Breeding of Hyphomicrobium denitrificans for high production of pyrroloquinoline quinone by adaptive directed domestication / 生物工程学报

Pyrroloquinoline quinone (PQQ) is widely distributed in organisms and has physiological functions such as boosting body growth, maintaining mitochondrial function, promoting synthesis of nerve growth factor and regulating free radical levels in the body. It has broad application prospects in the fields of medicine, food and cosmetics. In order to improve the PQQ production of Hyphamicrobium denitrificans FJNU-6, the high-concentration methanol was used as the antagonistic factor for laboratory adaptive domestication. The PQQ positive mutants were selected using rapid screening system by spectroscopy. After 6 rounds of adaptive domestication, about 10% mutants were acquired with a doubled yield, and over 90% positive mutation rate of each round of domestication was reached. Subsequently, the mutant strain FJNU-R8 was fermented by 5 L fermenter. Compared with the original strain, the expression of pqq and moxF gene clusters were higher at different methanol concentrations and similar to each other. Meanwhile, the methanol consumption rate and growth rate were slower than the original strain. Finally, the PQQ yield was increased by 1.42 times to 1 087.81 mg/L (143 h), indicating good industrial application potential. The adaptive domestication combined with rapid screening system described in this study can easily and rapidly obtain mutants with high yield of PQQ, which can be used as reference for high-throughput screening of other high-yield PQQ mutants of methylotrophic bacteria.

Ajoene, a Major Organosulfide Found in Crushed Garlic, Induces NAD(P)H:quinone Oxidoreductase Expression Through Nuclear Factor E2-related Factor-2 Activation in Human Breast Epithelial Cells

BACKGROUND: NAD(P)H:quinone oxidoreductase-1 (NQO1) is a widely-distributed flavin adenine dinucleotide-dependent flavoprotein that promotes obligatory 2-electron reductions of quinones, quinoneimines, nitroaromatics, and azo dyes. This reduces quinone levels and thereby minimizes generation of excess reactive oxygen species (ROS) formed by redox cycling, and concurrent depletion of intracellular thiol pools. Ajoene is derived from crushed garlic. It is formed by a reaction involving two allicin molecules, and is composed of allyl sulfide and vinyl disulfide. Ajoene is present in two isomers, E- and Z-form. METHODS: Expression of antioxidant enzymes and nuclear factor E2-related factor-2 (Nrf2) was measured by Western blot analysis. NQO1 promoter activity was assessed by the luciferase reporter gene assay. ROS accumulation was monitored by using the fluorescence-generating probe 2′,7′-dichlorofluorescein diacetate. The intracellular glutathione levels were measured by using a commercially available kit. RESULTS: Z-ajoene significantly up-regulated the expression of representative antioxidant enzyme NQO1 in non-tumorigenic breast epithelial MCF-10A cells at non-toxic concentrations. Z-ajoene enhanced up-regulation and nuclear translocation of Nrf2, which plays a pivotal role in the induction of many genes encoding antioxidant enzymes and other cytoprotective proteins. Z-ajoene treatment also increased the activity of nqo1-promoter harboring antioxidant response element consensus sequences in MCF-10A cells. Silencing of Nrf2 by small interfering RNA abrogated ajoene-induced expression of NQO1. Z-ajoene activated extracellular signal-regulated kinase (ERK). Inhibition of ERK activation by U0126 abrogated ability of Z-ajoene to activate Nrf2 and to induce NQO1 expression. Intracellular ROS accumulation was observed after treatment with Z-ajoene, whereas the E-isoform was not effective. The inhibition of ROS by treatment with N-acetylcysteine, a radical scavenger, abrogated Z-ajoene-induced expression of NQO1 as well as activation of ERK and Nrf2, suggesting that Z-ajoene augments the Nrf2-dependent antioxidant defense via ROS generation and ERK activation. CONCLUSIONS: Z-ajoene induces NQO1 expression in MCF-10A cells through ROS-mediated activation of Nrf2.

Current research on the influence of genetic factors on warfarin maintenance dose / 中国胸心血管外科临床杂志

@#Warfarin is one of the most frequently prescribed oral anticoagulant. Many researches have shown that the genotypes have been strongly associated with warfarin maintenance doses. Especially, it has been accepted in academia that cytochrome P450 2C9 (CYP2C9) and vitamin K epoxide reductase complex 1 subunit (VKORC1) could affect the warfarin maintenance doses. There are also many other genotypes that were reported to be related to warfarin doses, but the results have been in controversial so far. The studies found that the dose formula which contained the genetic factors and clinical information could accurately predict the maintenance dose of warfarin, however, its usefulness is suspected due to the inconsistent results of clinical trials. Large-sample and multi-center studies are necessary to verify the specific effects of gene and non-gene factors to warfarin dose; at the same time, testing constructed models or building new models help to improve the explained percentages of individual differences.

Optimization of Extraction Process for Walnut Quinone from Juglans Green Peel by Box-Behnken Response Surface / 中国中医药信息杂志

Objective To optimize extraction process of walnut quinone from Juglans green peel. Methods On the basis of single factor tests, taking material-liquid ratio, extracting temperature and ethanol concentration as independent variables, yield of walnut quinone in response to as a value, according to Box-Behnken experiment design principle, extraction process of walnut quinone from Juglans green peel was optimized by response surface analysis. Results The optimum extraction process of walnut quinone was: 14.30 times the amount of 89.81% ethanol;30.28 ℃ constant temperature. The extracting amount of walnut quinone was 2.034 mg/g, which was close to the experimental results of 1.957 mg/g. Conclusion The optimized extraction process is reasonable and feasible, which can provide reference for the extraction of walnut quinone from Juglans green peel.

Expression and significance of NAD (P) H: quinone oxidoreductase 1 and heme oxygen-ase-1 proteins in T-cell lymphoma / 中国肿瘤临床

Objective: To investigate the expression of NAD (P) H: quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) in T-cell lymphoma (TCL), and investigate the correlation between these two indicators and other clinicopathological parameters in TCL. Methods: Clinical data of 61 patients with TCL who were initially diagnosed in Gansu Provincial Hospital were analyzed retrospectively. Immunohistochemical examination was performed to detect NQO1 and HO-1 expression levels in 61 TCL tissues (TCL group) and 20 lymph node reactive hyperplasia tissues (control group). Results: Positive expression rates of NQO1 and HO-1 were significantly higher in TCL tissues than in lymph node reactive hyperplasia tissues (P<0.05). NQO1 expression was closely related with Ann-Arbor clinical stage and B symptoms (P<0.05); HO-1 expression was correlated with clinical stage, bone marrow invasion, and B symptoms (P<0.05). NQO1 and HO-1 expression levels were not related to age, sex, lactate dehydrogenase level, and pathological type (P>0.05); there was a correlation between NQO1 and HO-1 expression (r=0.264; P=0.040). Conclusions: NQO1 and HO-1 are highly expressed in TCL and may interact and contribute to the occurrence and development of TCL.

High-throughput screening of Methylobacterium extorquens for high production of pyrroloquinoline quinone / 生物工程学报

Pyrroloquinoline quinone (PQQ) is a bacterial dehydrogenase coenzyme. PQQ can promote body growth and regulate the function of free radical level of the body. It could be applied in food, medicine and other fields. Due to the extremely high cost of chemical synthesis, the production of PQQ by microbial fermentation attracted more and more attention. At present, the production titer of PQQ by fermentation method is too low to achieve industrial application. Due to the lack of a thorough understanding of the PQQ biosynthesis and its regulation mechanisms, and the lack of necessary genetic engineering modification methods for wild type strains, metabolic engineering of microorganisms to enhance PQQ production still lacks essential requirements. In this study, a PQQ-producing bacterium, Methylobacterium extorquens I-F2, was employed as a model strain. By integration of Atmospheric and room temperature plasma (ARTP) mutagenesis, flow cytometry sorting and high-throughput screening strategies, optimization of sample preparation and flow sorting process, a high-titer PQQ mutant strain was obtained. The titer of PQQ was increased by 98.02% compared with that of M. extorqunens I-F2. The process described here showed that the combination of the flow cytometry with high-throughput screening method can be used to obtain high-titer mutants more simply and rapidly, compared with genetic engineering and traditional screening methods.

Evaluación mecanística matemática del desempeño de electrodo polimérico conductor, modificado por fragmentos de safranina, en la detección de compuestos hidroquinónicos. Posible ejemplo de galato de propilo / Mechanistic mechanism evaluation of the performance of polymeric conductor electrode, modified by fragments of safranin, in the detection of hydroquinonic compounds. Possible example of propyl gallate

RESUMEN Se evaluó teóricamente el desempeño electroanalítico de un electrodo polimérico conductor, modificado por fragmentos de safranina, en la cuantificación electroquímica de compuestos hidroquinónicos (con el ejemplo de galato de propilo). El modelo matemático correspondiente se evaluó mediante la teoría de estabilidad lineal y de análisis de bifurcaciones. El desempeño de safranina como modificadora de electrodo se comparó con el de las otras sustancias modificadoras. La presencia de inestabilidades electroquímicas también se averiguó.

SUMMARY The electroanalytical performance of a conducting polymer electrode, modified by safranin fragments, was theoretically evaluated in the electrochemical quantification of hydroquinone compounds (with the example of propyl gallate). The corresponding mathematical model was evaluated using linear stability theory and bifiir-cation analysis. The performance of safranin as an electrode modifier was compared to that of the other modifying substances. The presence of electrochemical instabilities was also investigated.

Effect of pyrroloquinoline quinone on learning and memory ability of apolexis rats / 中国食品卫生杂志

Objective This study aimed to investigate the role of pyrroloquinoline quinone (PQQ) in repairing oxidative nerve cells,and to study the antioxidant capacity of PQQ on the oxidative damage of rats caused by apolexis,as well as the effects on learning and memory abilities of apolexis rats.Methods Oxidative damage of PC12 was induced by H2O2,and the repairing rate of PQQ on oxidative PC12 cells was tested by methylthiazolyldiphenyl-tetrazolium bromide assay kit.The 18-month-old male SD rats were administered PQQ (0,10,20,40 mg/kg).After 4 weeks,Morris water maze test was used to test the learning and memory ability.After 6 weeks,serum and brain tissue related indicators and antioxidant capacity were recorded.Results The survival rate of PC12 cells increased from 59.1％ to 90.5％ with 200 nmol/L PQQ.Compared with the apolexis model group,the latency of the PQQ group (20,40 mg/kg) was shortened in the Morris water maze experiment,the swimming distance was reduced,pass-through counts were increased,and the first secure platform pass-through was reduced.Meanwhile,the levels of malondialdehyde and lipofuscin in serum and brain tissue of PQQ group decreased,the levels of superoxide dismutase,glutathione peroxidase vitality,antioxidant capacity of PQQ group (20,40 mg/kg) were enhanced.Conclusion PQQ could repair the oxidative damage of nerve cells,and it was confirmed that PQQ could play the same antioxidant effect in body and brain,and increase the learning and memory ability of apolexis rats.

Early events of norcantharidin reactive oxygen species and NF-E2-related factor 2/antioxidant response element pathway of HepG2 cells / 中国药理学与毒理学杂志

OBJECTIVE To investigate the early events of norcantharidin (NCTD) induced cell apoptosis and cell cycle arrest, the variation of reactive oxygen species (ROS) and the NF-E2-relate? dactor 2/antioxidant response element(Nrf2/ARE) pathway in human HepG2 cells. METHODS The cyto?toxicity was measured by MTT assay. Apoptosis and cell cycle was analyzed by flow cytometry. The intra toxicity ROS production was evaluated by flow cytometry analysis with DCFH-DA probe and the effect of NCTD on Nrf2/ARE pathway was detected by luciferase assay in HepG2C8 cells under the same condition. The mRNA expression of heme oxygenase-1(HO-1) and NAD(P)H: quinone oxidoreductase 1(NQO1) antioxidase gene in Nrf2/ARE pathway downstream was evaluated by quantitative real-time PCR. RESULTS No significant cytotoxicity was detected after HepG2 cells were treated with NCTD 30, 60 and 120 μmol · L- 1 for 3 and 6 h, but cellular viability was inhibited significantly by NCTD 30, 60 and 120μmol·L-1 for 24, 48 and 72 h(P<0.01). Cell apoptosis and G2/M phase arrest occurred after HepG2 cells were treated with NCTD 60μmol · L-1 for 12, 24 and 48 h. The percentage of apoptosis increased from (4.00 ± 1.98)%to (12.10 ± 1.70)%for 12 h, from (4.05 ± 0.21)%to (31.8 ± 6.50)%for 24 h, and from (3.90 ± 0.85)% to (33.30 ± 1.41)% for 48 h, respectively. The percentage of G2/M phase increased from (16.51 ± 1.58)% to (40.89 ± 0.18)% for 12 h, from (16.99 ± 1.32)% to (55.29 ± 3.99)% for 24 h, and from (14.45 ± 0.59)% to (50.66 ± 5.88)% for 48 h, respectively. Compared with cell control group, the percentage of G1 phase had a significant decrease in the group with NCTD treated at different time points(P<0.01). No significant change in ROS in HepG2 cells was detected after the treatment with NCTD 30, 60 and 120μmol · L-1 for 3, 6 and 12 h. Nrf2/ARE pathway in HepG2C8 cells was activated by NCTD 30, 60 and 120μmol·L-1 for 6 and 12 h. mRNA expression of HO-1 and NQO1 had a signifi?cant activation in HepG2 cells after treatment with NCTD 30, 60 and 120 μmol · L-1 for 6 and 12 h (P<0.05). CONCLUSION NCTD can activate Nrf2/ARE pathway in the early stage in HepG2 cells, which may inhibit the intracellular ROS production in the early stage. Activation of ROS may not be the main event in NCTD induced HepG2 cell apoptosis and G2/M phase arrest.

Effect of NQO1 and NQO2 expression in clinical prognosis of ovarian carcinoma / 重庆医学

Objective To investigate the effect of quinone oxidoreductase 1 (NQO1) and quinone oxidoreductase 2 (NQO2) expression in the prognosis of ovarian carcinoma.Methods The two online databases were used to perform the online analysis on the NQO1 and NQO2 mRNA levels and prognosis of ovarian cancer patients,1 306 cases of ovarian cancer were performed the Kaplan-Meier analysis by using the KaplanMeier plotter (K-M plotter);578 cases of ovarian cancer in the TCGA database were performed the univariate COX regression survival analysis.Results The K-M plotter analysis showed that the NQO1 expression level had no obvious correlation with the prognosis of ovarian cancer (P>0.05),the higher the NQO2 level,the better the prognosis (HR=0.83,P=0.006 2).The COX regression survival analysis showed that the NQO1 expression level had no obvious correlation with the prognosis of ovarian cancer(P>0.05),the higher the NQO2 level,the better the prognosis (P=0.038 29).Conclusion NQO2 expression level has no obvious correlation with the prognosis of ovarian cancer,moreover the higher the NQO2 expression level,the better the clinical prognosis of ovarian cancer.

Biased activity of soluble guanylyl cyclase: the Janus face of thymoquinone

The natural compound thymoquinone, extracted from(black cumin), is widely used in humans for its anti-oxidative properties. Thymoquinone is known for its acute endothelium-independent vasodilator effects in isolated rat aortae and pulmonary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium channels and inhibition of voltage-dependent calcium channels. The compound also improves endothelial dysfunction in mesenteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously, thymoquinone was found to augment contractions in isolated arteries with endothelium of both rats and pigs. The endothelium-dependent augmentation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase (sGC) producing inosine 3',5'-cyclic monophosphate (cyclic IMP) rather than guanosine 3',5'-cyclic monophosphate. This phenomenon shows a striking mechanistic similarity to the hypoxic augmentation previously observed in porcine coronary arteries. The cyclic IMP preferentially produced under thymoquinone exposure causes an increased contractility of arterial smooth muscle by interfering with calcium homeostasis. This brief review summarizes the vascular pharmacology of thymoquinone, focussing in particular on how the compound causes endothelium-dependent contractions by biasing the activity of sGC.

Isocartormin, a novel quinochalcone-glycoside from

A new semi-quinonechalcone-glycoside isocartormin along with cartormin and safflomin C were isolated from the water extract ofL. The structure of isocartormin was determined by extensive analysis of HR-MS, 1D- and 2D NMR data, and by comparison with those of cartormin reported previously by our group. Isocartormin was identified as a diastereoisomer of cartormin with a reverse configuration at C-18.

Pyrroloquinoline quinone inhibited oxidative stress induced-apoptosis of Schwann cells via mitochondrial apoptotic signaling pathway in vitro / 中华整形外科杂志

Objective@#To investigate the mechanisms of Pyrroloquinoline quinone (PQQ) against oxidative stress induced apoptosis in Schwann cells (SCs).@*Methods@#SCs were cultured in vitro, identified by S-100 immunofluorence staining. SCs were divided into control group, H2O2 induced group, H2O2 + PQQ treated group. CCK-8 assay was used to detect cell proliferation. Apoptosis was detected by flow cytometry with Annecin V-FITC/PI staining, mitochondrial transmembrane potential was detected by flow cytometry with JC-1 labeled staining, cytochrome C (CytC), Bax and Caspase-9 protein levels was detected by Western blot analysis.@*Results@#In this study, the S-100 positive cells were more than 95%, cell proliferation was decreased in H2O2 induced SCs, apoptotic rate was increased, mitochondrial transmembrane potential was decreased, CytC, Bax and Caspase-9 protein levels were increased. After PQQ added, cell proliferation was increased, apoptotic rate decreased, mitochondrial transmembrane potential increased, CytC, Bax and Caspase-9 protein levels decreased.@*Conclusions@#PQQ protects SCs from oxidative induced apoptosis by inhibiting mitochondrial signaling pathway.