Effect of H2O2 on Secondary Metabolism in Atractylodes chinensis and Its Mechanism / 中国实验方剂学杂志

ObjectiveTo investigate the effect of exogenous H2O2 on secondary metabolism in Atractylodes chinensis and its mechanism. MethodFresh rhizomes of A. chinensis were treated with 5.0， 1.0， 0.2， 0.04 mmol·L-1 H2O2 solution and clean water， and the relationships between the contents of reactive oxygen species， activities of antioxidant enzymes， activities of key enzymes of secondary metabolites， and contents of secondary metabolites in A. chinensis were compared. ResultUnder treatment with exogenous H2O2， the content of reactive oxygen species and malondialdehyde （MDA） in the fresh rhizomes of A. chinensis were significantly elevated on the 4th day， and returned to normal level on the 6th-8th day. The activities of superoxide dismutase （SOD）， catalase （CAT） and peroxidase （POD） were all increased first and then decreased， and reached the peak on the 4th， 4th-6th and 2th-4th day， respectively. The activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase （HMGR） and acetyl CoA carboxylase （ACC）， key enzymes of the secondary metabolites， were remarkably enhanced， and under treatments with different concentrations of H2O2， the activities of key synthetic enzymes of the secondary metabolites in 0.2 mmol·L-1 H2O2 group were increased most， with the highest biosynthesis of secondary metabolites. The contents of atractylodin， β-eudesmol， atractylone， atractylenolide Ⅱ， and atractylenolide Ⅲ on the 6th day of 0.2 mmol·L-1 H2O2 treatment were 89.5%， 108.7%， 308.8%， 64.7% and 9.3%， respectively higher than those in the control. ConclusionThe antioxidant enzymes and secondary metabolites in A. chinensis synergistically maintain the balance of reactive oxygen species， and exogenous H2O2 can improve the medicinal quality of A. chinensis remarkably.

Highly sensitive H2O2-scavenging nano-bionic system for precise treatment of atherosclerosis

In atherosclerosis, chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species (ROS). In this study, we devised a highly sensitive H2O2-scavenging nano-bionic system loaded with probucol (RPP-PU), to treat atherosclerosis more effectively. The RPP material had high sensitivity to H2O2, and the response sensitivity could be reduced from 40 to 10 μmol/L which was close to the lowest concentration of H2O2 levels of the pathological environment. RPP-PU delayed the release and prolonged the duration of PU in vivo. In Apolipoprotein E deficient (ApoE‒/‒) mice, RPP-PU effectively eliminated pathological ROS, reduced the level of lipids and related metabolic enzymes, and significantly decreased the area of vascular plaques and fibers. Our study demonstrated that the H2O2-scavenging nano-bionic system could scavenge the abundant ROS in the atherosclerosis lesion, thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.

Genetic regulation of the ompX porin of Salmonella Typhimurium in response to hydrogen peroxide stress

BACKGROUND: Salmonella Typhimurium is a Gram negative pathogen that causes a systemic disease in mice resembling typhoid fever. During its infective cycle, S. Typhimurium is phagocytized by macrophages and proliferates inside a Salmonella containing vacuole where Salmonella is exposed and survives oxidative stress induced by H2O2 through modulation of gene expression. After exposure of Salmonella to H2O2, the expression of the porin encoding gene ompX increases, as previously shown by microarray analysis. Expression of ompX mRNA is regulated at a post transcriptional level by MicA and CyaR sRNAs in aerobiosis. In addition, sequence analysis predicts a site for OxyS sRNA in ompX mRNA. RESULTS: In this work we sought to evaluate the transcriptional and post transcriptional regulation of ompX under H2O2 stress. We demonstrate that ompX expression is induced at the transcriptional level in S . Typhimurium under such conditions. Unexpectedly, an increase in ompX gene transcript and promoter activity after challenges with H2O2 does not translate into increased protein levels in the wild type strain, suggesting that ompX mRNA is also regulated at a post transcriptional level, at least under oxidative stress. In silico gene sequence analysis predicted that sRNAs CyaR, MicA, and OxyS could regulate ompX mRNA levels. Using rifampicin to inhibit mRNA expression, we show that the sRNAs (MicA, CyaR and OxyS) and the sRNA:mRNA chaperone Hfq positively modulate ompX mRNA levels under H2O2 induced stress in Salmonella during the exponential growth phase in Lennox broth. CONCLUSIONS: Our results demonstrate that ompX mRNA is regulated in response to H2O2 by the sRNAs CyaR, MicA and OxyS is Salmonella Typhimurium.

Preparation and characterization of fenugreek leaf flavonoids and their protective effects against oxidative damage to hepatocytes / 中国中药杂志

The present study investigated the main components of fenugreek(Trigonella foenum-graecum L.) leaf flavonoids(FLFs) and their antioxidant activity. FLFs were prepared and enriched by solvent extraction, and the flavonoids were characterized by high-performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry(HPLC-Q-TOF-MS/MS). The protective effect of FLFs against H_2O_2-induced stress damage to L02 hepatocytes was also investigated. Firstly, the cell viability was measured by MTT assay. The oxidative stress injury model was induced by H_2O_2 in L02 cells. The release of lactate dehydrogenase(LDH), the content of reduced glutathione(GSH) and malondialdehyde(MDA), and the activities of superoxide dismutase(SOD) and catalase(CAT) were measured by assay kits. Hoechst fluorescence staining was performed to observe the cell apoptosis. The expression levels of c-Jun N-terminal kinase(JNK), extracellular signal-regulated kinase 1/2(ERK1/2), nuclear factor erythroid-2 related factor 2(Nrf2), heme oxygenase 1(HO-1), and their phosphorylated proteins were detected by Western blot. Based on the MS fragment ion information and data in databases, FLFs contained eight flavonoids with quercetin and kaempferol as the main aglycons. The cell viabi-lity assay revealed that as compared with the conditions in the H_2O_2 treatment group, 3.125-25 μg·mL~(-1) FLFs could increase the viability of L02 cells, reduce LDH release and MDA content in a dose-dependent manner, potentiate the activities of SOD, CAT, and GSH, decrease the phosphorylation of JNK and ERK1/2 proteins, and up-regulate the expression of Nrf2 and HO-1. The results of fluorescence staining showed that the nucleus of the H_2O_2 treatment group showed concentrated and dense strong blue fluorescence, while the blue fluorescence intensity of the FLFs group decreased significantly. FLFs showed a protective effect against H_2O_2-induced oxidative damage in L02 cells, and the underlying mechanism is associated with the enhancement of cell capability in clearing oxygen free radicals and the inhibition of apoptosis by the activation of the MAPKs/Nrf2/HO-1 signaling pathway. The antioxidant effect of fenugreek leaf is related to its rich flavonoids.

A new method for isolating gas vesicles from Microcystis for ultrasound contrast / 生物工程学报

Gas vesicles are a unique class of gas-filled protein nanostructures which are commonly found in cyanobacteria and Halobacterium. The gas vesicles may scatter sound waves and generate harmonic signals, which enabled them to have the potential to become a novel ultrasound contrast agent. However, the current hypertonic cracking method for isolating gas vesicles contains tedious operational procedures and is of low yield, thus not suitable for large-scale application. To overcome these technical challenges, we developed a rapid and efficient method for isolating gas vesicles from Microcystis. The new H2O2-based method increased the yield by three times and shortened the operation time from 24 hours to 7 hours. The H2O2 method is not only suitable for isolation of gas vesicles from laboratory-cultured Microcystis, but also suitable for colonial Microcystis covered with gelatinous sheath. The gas vesicles isolated by H2O2 method showed good performance in ultrasound contrast imaging. In conclusion, this new method shows great potential for large-scale application due to its high efficiency and wide adaptability, and provides technical support for developing gas vesicles into a biosynthetic ultrasonic contrast agent.

Biological and Oxidative Effect of Ellagic Acid on Saccharomyces cerevisiae: A New Way for Culture Developing

Abstract In this study, the effects of Ellagic acid (EA) on protein expression in yeasts and cellular development were investigated. Four groups were formed. Groups: 1) Control group; yeast only cultivated group; 2) Ellagic Acid (EA) group: EA (10%) given group; 3) Hydrogen peroxide (H2O2) Group: The group given H2O2 (15 mM); 4) EA + H2O2 group: EA (10%) + H2O2 (15 mM) group. After sterilization, EA (10%) and H2O2 (15 mM) were added to the Saccharomyces cerevisiae (S. cerevisiae) cultures and the cultures were grown at 30 °C for 1 hour, 3 hours, 5 hours and 24 hours (overnight). S. cerevisiae cell growth, lipid peroxidation MDA (malondialdehyde) analysis and GSH (glutathione) level were analyzed by spectrophotometer. Total protein changes were determined by SDS-PAGE electrophoresis and measured by the Bradford method. According to the obtained results, compared with the H2O2 group, cell development (1, 3, 5 and 24 hours), GSH level and total protein synthesis (24 hours) were increased with EA, while MDA level (24 hours) decreased. These results show that EA reduces oxidative damage, increases cell growth and it has a protective effect to promote protein synthesis in S. cerevisiae culture.

Protective effect of recombinant / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

This study probed the protective effect of recombinant

Protective effect of paeoniflorin on H / 中国天然药物

This study was to investigate the protective effect of paeoniflorin (PF) on hydrogen peroxide-induced injury. Firstly, "SMILES" of PF was searched in Pubchem and further was used for reverse molecular docking in Swiss Target Prediction database to obtain potential targets. Injury-related molecules were obtained from GeenCards database, and the predicted targets of PF for injury treatment were selected by Wayne diagram. For mechanism analysis, the protein-protein interactions were constructed by String, and the KEGG analysis was conducted in Webgestalt. Then, cell viability and cytotoxicity assay were established by CCK8 assay. Also, the experimental cells were allocated to control, model (200 μmol·L

Effect of silencing SIAH1 gene on H2O2-induced apoptosis of human lens epithelial cells / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the effect of silencing SIAH1 gene on H2O2-induced apoptosis of human lens epithelial cells.<p>METHODS: The human lens epithelial cell line HLE-B3 was cultured and divided into normal group, H2O2 group(cultured with medium containing 400μmol/L H2O2)and H2O2+siR-SIAH1 group(transfected with SIAH1 interference sequence, followed by cultured with medium containing 400μmol/L H2O2)and siR-NC group(transfected with negative control sequence, followed by cultured with medium containing 400μmol/L H2O2). The expression of SIAH1 gene in cells was detected by real-time fluorescent quantitative PCR. The apoptosis rate was detected by flow cytometry. The expressions of p38 MAPK, p-p38 MAPK, Bcl-2 and Bax proteins were detected by Western blot.<p>RESULTS: The relative expression levels of SIAH1 mRNA in the H2O2 group, siR-NC group and H2O2+siR-SIAH1 group were higher than that in the normal group(<i>P</i><0.05). The relative expression level of SIAH1 mRNA in H2O2+siR-SIAH1 group was lower than those in the H2O2 group and siR-NC group(<i>P</i><0.05). The apoptosis rates in the H2O2 group, siR-NC group and H2O2+siR-SIAH1 group were higher than that in the normal group(<i>P</i><0.05). The apoptosis rate in the H2O2+siR-SIAH1 group was lower than those in the H2O2 group and siR-NC group(<i>P</i><0.05). The expression levels of p38 MAPK and Bcl-2 proteins in the H2O2 group, siR-NC group and H2O2+siR-SIAH1 group were lower than those in the normal group, while the expression levels of p-p38 MAPK and Bax proteins were higher than those in the normal group(<i>P</i><0.05). The expression levels of p38 MAPK and Bcl-2 proteins in the H2O2+siR-SIAH1 group were higher than those in the H2O2 group and siR-NC group, while the expression levels of p-p38 MAPK and Bax proteins were lower than those in the H2O2 group and siR-NC group(<i>P</i><0.05).<p>CONCLUSION: Down-regulation the expression of SIAH1 gene could inhibit H2O2-induced apoptosis of human lens epithelial cell line HLE-B3, which might be related to inhibition of p38 MAPK signaling pathway activation.

Establishment and significance of pyrolysis model of human trophoblast HTR-8/SVneo induced by hydrogen peroxide / 医学研究生学报

ObjectiveA good invasion ability of extravilloustrophoblas (EVTs) is the prerequisite for successful placental colonization and effective remodeling of the uterine spiral artery. This article aims to simulate the pathophysiological process of oxidative stress inducing trophoblasts to pyroptosis in vitro, exploring the correlation between trophoblasts pyroptosis and the pathogenesis of preeclampsia.MethodsTwenty-five patients with preeclampsia were selected from the Department of Obstetrics and Gynecology, Zhongda Hospital affiliated to Southeast University from September 2017 to January 2019. Among them, early-onset preeclampsia (gestational weeks<34) was early-onset group (n=17), late-onset preeclampsia (gestational weeks≥34) was late-onset group (n=8), and full-term pregnant women with normal blood pressure (39＜gestational weeks＞42) were selected as normal group (n=10). Human trophoblasts were cultured with HTR-8/SVneo for 12 hours, and then treated with H2O2 (100, 150, 200, 250μmol/L) (2, 4, 6, 12 h), to induce human trophoblast HTR-8/SVneo pyrolysis model; the control group was normal cultured cells of 1640+10% fetal bovine serum + 1% antibiotics. Placental specimens from 7 patients with preeclampsia were randomly selected, including 3 cases in early onset group, 4 cases in late onset group and 1 case in normal group. The total proteins of cells and placenta were extracted respectively, and the expression of scorch death-related molecular proteins was detected. The mRNA levels of pyroptosis related molecules in cells was detected by RT-qPCR, and the morphological changes of cells were observed by inverted phase contrast microscope.ResultsThe Western blot results showed that the activation of the key molecular activation form of the cell pyrogenesis pathway, Cleaved caspase1, could be detected in the placenta. When H2O2 was 150 mol/L for 2h, the mRNA levels of NLRP3 and IL-1, the key molecules of the upstream activation signal, were significantly up-regulated (8.680±0.481, 14.136±0.244) compared with the control group (1.00±0.00) (P<0.000). At 4h, mRNA levels of key molecule GSDMD and downstream inflammatory factor IL-18 (1.639±0.354 and 1.794±0.043) in the pyrogenesis pathway were significantly higher than those in the control group (1.00±0.00), with statistically significant differences (P<0.05). By reverse validation of the mRNA levels of the molecules associated with pyroptosis, the optimal conditions of the model induced by H2O2 were 150 mol/L and 4h, and the typical changes, such as cell swelling, fragmentation and plasma membrane bubble formation, could be seen under the light microscope.ConclusionThe pyroptosis model of trophoblast cells was successfully established, and the physiological process of oxidative stress inducing trophoblasts to pyroptosis in vitro was successfully simulated, providing new ideas and directions for the diagnosis and treatment of preeclampsia and the development of new drugs.

Protective effects of Rhein on cardiomyocyte induced with H2O2 / 医学研究生学报

ObjectiveThe effect of Rhein on myocardial cell injury and its possible mechanism of action remains unknown. This study aims to explore the effect and mechanism of rhein on cardiomyocyte injury induced by hydrogen peroxide (H2O2).MethodsRat cardiomyocyte H9c2 was stimulated using H2O2 to establish the myocardial cell injury model. The experiment was divided into three groups including a control group, H2O2 induced group, and Rhein treated group. Fluorescence probe and biochemical methods were used to detect the oxidative stress level of H9c2 cells. RT-qPCR and immunofluorescence tests were adapted to determine the apoptosis of H9c2 cells. Besides, RT-qPCR was carried out to evaluate the inflammatory response of H9c2 cells. Finally, western blot assay was performed to evaluate the expression of MAPK and NF-κB signaling pathways.ResultsThe results of fluorescence probe showed that the expression of ROS of H9c2 cells induced by H2O2 was decreased significantly after Rhein intervention. Besides, the biochemical test showed that the expressions of GSK-Px and CAT of H9c2 cells induced by H2O2 were increased significantly after Rhein treatment. RT-qPCR data suggested that Rhein could significantly decrease the mRNA expressions of Bax, caspase-3 and caspase-9, and upregulate the mRNA expression of Bcl-2 of H9c2 cells induced by H2O2. Moreover, immunofluorescence experiments showed that Rhein could significantly inhibit the expression of caspase-3 of H9c2 cells induced with H2O2. Further, the results of RT-qPCR indicated that the mRNA expressions of IL-6, TNF-α、IL-1β and IL-1α of H9c2 cells induced by H2O2 was decreased significantly after Rhein intervention. Finally, western blot showed that Rhein can significantly inhibit the expressions of MAPK and NF-κB signaling pathways.ConclusionRhein can reduce the injury of cardiomyocytes induced by H2O2, which may be achieved by inhibiting the expressions of MAPK and NF-κB signaling pathways.

Water extract of mangosteen suppresses H2O2-induced endothelial apoptosis by inhibiting oxidative stress

Excessive production of reactive oxygen species (ROS) is a major cause of endothelial apoptosis. Mangosteenextract has been shown to possess antioxidant properties. Mangosteen is commonly extracted either with semi-polarsolvent, yielding virtually pure α-mangostin, or with water, yielding a low α-mangostin concentration but includinga wide variety of other polyphenols present in the fruit. However, the effect of a water extract of mangosteen(ME) on ROS induced cell death is not yet known. This study evaluated whether ME suppresses H2O2-inducedendothelial cell death and ROS production in human endothelial cell lines. The concentrations of ME and H2O2were determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. IntracellularROS levels were determined by 2', 7' dichlorodihydrofluorescein diacetate assay, and cell death rates by MTT andTerminal deoxynucleotidyl transferase dUTP Nick-End Labeling assays. mitogen-activated protein kinase (MAPK)and apoptotic proteins were analyzed by western blot. Results showed that ME concentrations of 1, 5, and 10 µg/mlwere non-toxic. ME significantly attenuated ROS formation and cell death, both in a dose-dependent manner. MEalso reduced phosphorylation of p38 MAPK as well as cleavage of caspase 3 and poly(ADP-ribose) polymerase-1.In summary, ME demonstrates anti-apoptotic effects against H2O2-induced endothelial cell death by inhibiting ROSformation and suppressing p38 MAPK.

Tratamento de efluentes de lavanderia hospitalar por processo oxidativo avançado: UV/H2O2 / Wastewater treatment of hospital laundry by advanced oxidation process: UV/H 2 O 2

RESUMO O objetivo deste trabalho foi avaliar o tratamento de efluentes de lavanderia hospitalar por processo oxidativo avançado UV/H2O2. O planejamento fatorial 32 foi empregado de modo a avaliar a influência do pH e da dosagem de peróxido na eficiência do tratamento. Os experimentos de foto-oxidação foram realizados com efluentes coletados na lavanderia do Hospital Universitário Regional de Maringá (HUM). Resultados relativos à caracterização do efluente e às reduções de parâmetros físico-químicos: cor, turbidez, demanda biológica de oxigênio (DBO), surfactantes e a quantificação de coliformes totais e termotolerantes, também são apresentados neste trabalho. Foram testados três valores de pH - 5, 7 e 9 - e três dosagens de peróxido de hidrogênio nas razões de [DQO]:[H2O2] - 1:0,5, 1:2,5 e 1:5. Os melhores resultados foram alcançados com o tratamento realizado em pH 9 e razão [DQO]:[H2O2] de 1:2,5. As eficiências de remoção da demanda química de oxigênio (DQO) e de surfactantes foram, em média, de 60,3 e 98%, respectivamente, porém o tratamento não se mostrou eficiente na redução de cor e turbidez, demonstrando a necessidade de se acoplar tratamentos complementares para a redução de tais parâmetros.

ABSTRACT The objective of this work was to evaluate the treatment of hospital laundry effluents by advanced oxidation process UV/H2O2. Factorial design 32 was employed to investigate the influence of pH and peroxide dosage on treatment efficiency. The photo-oxidation experiments were performed with effluents collected in the laundry of the Regional University Hospital of Maringá (HUM). Physicochemical parameters of effluent color, turbidity, BOD, surfactants and quantification of total and thermotolerant coliforms are presented in this study. Three values ​​of pH - 5, 7 and 9 - and three dosages of hydrogen peroxide with [COD]:[H2O2] ratios of 1:0.5, 1:2.5 and 1:5 (w:w) were tested. The best results were achieved with the treatment performed at pH 9 and ratio [COD]:[H2O2] of 1:2.5. The average removal efficiencies of COD and surfactants were 60.3 and 98%, respectively. However, the treatment was not efficient in reducing color and turbidity, demonstrating the need to combine complementary treatments for the reduction of such parameters.

Hydrogen sulfide protects H9c2 cardiomyoblasts against H2O2-induced apoptosis

Reactive oxygen species (ROS) are highly reactive chemical species that may cause irreversible tissue damage, and play a critical role in cardiovascular diseases. Hydrogen sulfide (H2S) is a gasotransmitter that acts as a ROS scavenger with cardio-protective effects. In this study, we investigated the cytoprotective effect of H2S against H2O2-induced apoptosis in cardiomyocytes. H9c2 rat cardiomyoblasts were treated with H2S (100 μM) 24 h before challenging with H2O2 (100 μM). Apoptosis was then assessed by annexin V and PI, and mitochondrial membrane potential was measured using a fluorescent probe, JC-1. Our results revealed that H2S improved cell viability, reduced the apoptotic rate, and preserved mitochondrial membrane potential. An increased Bcl-2 to Bax ratio was also seen in myocytes treated with H2S after H2O2-induced stress. Our findings indicated a therapeutic potential for H2S in preventing myocyte death following ischemia/reperfusion.

Effect of Picroside Ⅱ on Expression of microRNA-1 in H2O2-induced H9c2 Cardiomyocytes Damage / 中国实验方剂学杂志

Objective: To study the effect of picroside Ⅱ on the expression of microRNA-1 (miR-1) in the H2O2-induced H9c2 cardiomyocytes damage, in order to explore the mechanism of picroside Ⅱ in protecting H9c2 cardiomyocytes from oxidative stress. Method: H9c2 cardiomyocytes were divided into 6 groups:control group, model group (H2O2 200 μmol·L-1), picroside Ⅱ (50, 100, 200 μmol·L-1)+H2O2 (200 μmol·L-1) group and picroside Ⅱ (200 μmol·L-1) group. Picroside Ⅱ group was incubated with picroside Ⅱ for 6 h and then cultured with H2O2 for 2 h. At the end of drugs treatment, the cell viability and the cellular damage of cardiomyocytes were respectively assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. 4',6-diamidino-2-phenylindole (DAPI) staining and cysteinyl aspartate specific proteinase-3 (Caspase-3) test were used to evaluate cell apoptosis. The mRNA expressions of Caspase-3,B-cell lymphoma-2 (Bcl-2) and miR-1 were measured by Real-time polymerase chain reaction (Real-time PCR). The protein expression of Bcl-2 was detected by Western blot. Result:Compared with the control group, H2O2 could significantly decrease the cell viability and increase the rate of apoptosis, up-regulate mRNA expression of Caspase-3 and miR-1, and down-regulate expression of Bcl-2 in H9c2 cells (PPPPPPPConclusion:Picroside Ⅱ has a protective effect on H9c2 cells from H2O2-induced cardiomyocyte injury by down-regulating mRNA-1 expression and up-regulating the expression of the downstream Bcl-2.

Effect of Hydrogen Peroxide (H2O2) on Content of Total Phenol Flavonoids and Activity of Related Enzymes in Polygala tenuifolia Callus / 中国实验方剂学杂志

Objective:To study the changes in total phenolic and flavonoid content and antioxidant enzyme activity of Polygala tenuifolia callus in MS medium with different concentrations of H2O2,in order to explore the physiological mechanism of Polygala tenuifolia callus in adapting to H2O2 environmental stress at the cellular level. Method:Five gradients of 0,5,10,15,20 mmol·L-1 were set for H2O2 concentration and added to MS medium, with P. tenuifolia callus as the experimental material. Total phenols,total flavonoids and antioxidant enzyme activities of callus were determined after 5,10,15,20,25 d of culture,respectively. Result:The contents of total phenols and flavonoids were the highest when the concentration of H2O2 was 5 mmol·L-1 for 15 d. The SOD activity was the highest when the callus was cultured for 5 d and the exogenous H2O2 concentration was 5 mmol·L-1. POD activity was the highest at 25 d and 5 mmol·L-1 concentration of exogenous H2O2.CAT activity was the highest at 25 d and 15 mmol·L-1 concentration of exogenous H2O2. Conclusion:P. tenuifolia callus has the ability to adapt to the environmental stress of H2O2 at a certain concentration. When it is subjected to the environmental stress of H2O2,P. tenuifolia callus can alleviate the damage by regulating its secondary metabolites and protecting enzyme system. It can significantly promote the content of total phenols and flavonoids in secondary metabolites at 5-10 mmol·L-1. SOD activity was significantly increased at 5 d and the concentration of exogenous H2O2 of 5 mmol·L-1. POD activity was significantly increased at 25 d and the concentration of exogenous H2O2 of 5 mmol·L-1. CAT activity was significantly increased at 25 d and concentration of exogenous H2O2 of 15 mmol·L-1.

Exogenous niacin treatment increases NADPH oxidase in kiwifruit / O tratamento com niacina exógena NADPH oxidase em kiwis

Abstract Kiwifruit are a popular fruit worldwide; however, plant growth is threatened by abiotic stresses such as drought and high temperatures. Niacin treatment in plants has been shown to increase NADPH levels, thus enhancing abiotic stresses tolerance. Here, we evaluate the effect of niacin solution spray treatment on NADPH levels in the kiwifruit cultivars Hayward and Xuxiang. We found that spray treatment with niacin solution promoted NADPH and NADP+ levels and decreased both O2·- production and H2O2 contents in leaves during a short period. In fruit, NADPH contents increased during early development, but decreased later. However, no effect on NADP+ levels has been observed throughout fruit development. In summary, this report suggests that niacin may be used to increase NADPH oxidases, thus increasing stress-tolerance in kiwifruit during encounter of short-term stressful conditions.

Resumo Kiwis são uma fruta popular em todo o mundo; No entanto, o crescimento das plantas é ameaçado por estresses abióticos como a seca e as altas temperaturas. O tratamento com niacina em plantas mostrou aumentar os níveis de NADPH, aumentando assim a tolerância a stress abiótico. Aqui, avaliamos o efeito do tratamento com spray de solução de niacina sobre os níveis de NADPH nos cultivares de kiwis Hayward e Xuxiang. Descobrimos que o tratamento por spray com solução de niacina promoveu níveis de NADPH e NADP + e diminuiu a produção de O2·- e os teores de H2O2 nas folhas durante um curto período. Nos frutos, os teores de NADPH aumentaram durante o desenvolvimento precoce, mas diminuíram mais tarde. No entanto, não se observou qualquer efeito nos níveis de NADP + ao longo do desenvolvimento do fruto. Em resumo, este relatório sugere que a niacina pode ser utilizada para aumentar NADPH oxidases, aumentando assim a tolerância ao estresse em kiwis durante o encontro de condições estressantes de curto prazo.

Pathological Overview and Antioxidant Status of Thyme on H2O2-induced Spleen Tissues Damage

Objectives: To study the preventive effect of Thymus algeriensis essential oil (TAS) against hydrogen peroxide (H2O2)-induced spleen toxicity in rats. Materials and Methods: Rats were treated with Hydrophobic fractions of Thymus algeriensis (180 mg/kg body weight, n=6), H2O2 (0.1, 1 mmol/L body weight, n=6) and the exposure to both drugs orally for 15 days. Histological examination was performed and the levels of biochemical parameters and lipid peroxides were determined. Results: In spleen tissue protein, catalase, superoxide dismutase, and glutathione (GST, GPx and GSH) levels were increased significantly (P<0.05) in the essential oil pretreated rats when compared to H2O2. TAS decreased the intracellular malondialdehyde (MDA) levels in spleen tissues. Vascular congestion was seen in spleen of high dose H2O2-treated rats and normal architecture of tissues was observed in other groups. Conclusion: The biochemical parameters and histopathology examination support the cytoprotective effect of Thyme which could be attributed to terpenes.

Protective effect and mechanism of Qishen Yiqi Formula on mitochondrial structure and function of cardiomyocytes injured by H2O2 / 中草药

Objective: To establish a cell-based multi-parameter mitochondrial structure and functional evaluation system for hydrogen peroxide (H2O2) injury in cardiomyocytes and investigate the protective effect of Qishen Yiqi Formula on H9c2 cells and its mechanism. Methods: For the in vitro myocardial cell injury model, H9c2 cells were divided into control, model (H2O2), positive control (carbonyl cyanide-cyanomethoxy basic hydrazine, 5 μmol/L), and Qishen Yiqi Formula (0.2 mg/mL) groups, with three duplicates in each group, and were cultured in triplicate for 24 h with corresponding drugs, followed by 2 h H2O2 induction. H2O2 injury model was established with H9c2 cell line. Mitochondrial function and morphological texture were evaluated by Operetta high content imaging system. Mitochondrial respiration and bioenergetic metabolism states were measured by Seahorse Bioscience XF extracellular flux analyzer. Cardiomyocyte apoptosis were quantified by flow cytometry. Results: Qishen Yiqi Formula prevented the decrease of mitochondrial membrane potential and the increase of mitochondrial mass and improved mitochondrial morphological integrity. Functionally, Qishen Yiqi Formula increased basic oxygen consumption rate, ATP-linked oxygen consumption rate, maximum oxygen consumption, and the reserve capacity. It also reduced the apoptotic rate at early and end stage and increased the myocyte survival. Conclusion: Based on the structure and functional evaluation of the mitochondria, results indicated that the compound Qishen Yiqi Formula protected the H9c2 cells by improving the mitochondrial function and energy metabolism as well as reducing the apoptosis.

Protective Effect of Water-soluble Total Flavonoids from Isodon Lophanthoides var.gerardianus ( Benth.) H.Hara on H2 O2-induced LO2 Cells Damage / 中国药师

Objective:To explore the protective effect of the water-soluble total flavonoids from Isodon lophanthoides var.gerardia-nus (Benth.) H.Hara on LO2 cells damage.Methods:The cytotoxicity was evaluated by MTT cell viability determination to confirm the concentration range .Hepatocyte damage model was established by H 2 O2 treatment.After the oxidative stress hepatocyte was coin-cubated with WSTF at different concentrations for various times , the protective effect of WSTF on H 2 O2-induced hepatocyte damage was evaluated by MTT cell viability determination and the content determination of ALT , AST and MDA in cell supernatant .The inhibition of WSTF against H 2 O2-induced LO2 cells apoptosis was evaluated by the quantitative determination of Rhodamine 123 fluorescence and intracellular ROS.Results:The LO2 cells injured by 0.3 mmol· L-1 H2 O2 treatment for 4 h were used as the hepatocyte damage model.The concentration range of WSTF was 0.0312-0.125 mg· ml-1.WSTF could inhibit H2O2-induced injury in LO2 cells and obviously reduce ALT, AST and MDA.Moreover, WSTF could reverse mitochondrial membrane potential depolarization and decrease the amount of intracellular ROS .Conclusion:WSTF exhibits notable protective and curative effects on hepatocyte damage in vitro.