Rb1 protects endothelial cells from hydrogen peroxide-induced cell senescence by modulating redox status

Objectives Endothelial senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study investigates the effects of ginsenoside Rbl, a major constituent of ginseng,on H2O2-induced endothelial senescence.Methods Primary human umbilical vein endothelial cells（HUVECs） senescence was induced by H2O2 as judged by senescence-associated P-galactosidase assay （SA-P-gal）.Fntracellur superoxide dismutase（S0D1） activity and malondialdehyde（MDA） level were determined by commercial kit.S0D1 mRNA and protein expression were analyzed by real time PCR and Western blot.Reactive oxygen species（ROS） were determined by flow cytometry.Results Rb1 was found to reverse endothelial senescence,as witnessed by a significant decrease of senescent cell numbers. Rbl could markedly increase intracellular SOD activity, decrease the MDA level,and suppress the generation of intracellular ROS in H2O2-treated HUVECs.Consistent with these findings,Rbl can effectively restore SOD1 mRNA and protein expression which decreased in H2O2 treated cells. Conclusions Our report demonstrates thatRbl can exert reversal effects on H2O2-induced cellular senescence through modulating cellular redox status.

Effect of Potassium Nutrition of Different Varieties of Rice on the Redox Status in Microzone Rhizosphere Soils

Being divided into three groups-strong, moderate and weak-according to the different kinetic parameters (Fmax, km, Cmin) of potassium uptake by crops, 21 cultivars of rice have been studied to find out the relationships between their potassium nutrition and the oxidation-reduction status in the rhizosphere soils.Results show that, with no application of K fertilizer, there were higher contents of active reducing substances and ferrous iron in rhizosphere soils planted with cultivars, such as Zhongguo 91, week in absorbing potassium than in soils cropped with cultivars, Shanyou 64, stronger in absorbing potassium. As a result of K application, however, these toxic substances were decreased appreciably in the soil, particularly in the root zone where weakly K-absorbing cultivars were growing, and the parameter of soil redox (pH +pE) was increased, the most striking example of this being found in the rhizosphere soil where the more strongly K-absorbing cultivars were growing. On and close to the root surface in soils where rice plants were supplied with potassium fertilizer, rather more iron oxide had been accumulated compared with rice receiving no potash, and even greater amounts of red iron oxide precipitated on the rice root in neutral paddy soils. As shown by the concentration distribution of active reducing substances and ferrous iron in a microzone of the profile, the redox range of rice roots supplied with potassium may extend as far as several centimeters from the root surface. It can thus be seen that potassium nutrition exerts its effect first on the morphological properties of rice roots and their exudation of oxygen, then on the content of soluble oxygen and the count and species of oxygen-consuming microbes in the rhizosphere soil, and finally on the redox status of the soil.

3-56 Role of Redox Status in Radiosenisization

Generally, ROS are regarded as host defense molecules that are released by neutrophils to destroy exogenous pathogens such as bacteria and to act as secondary messengers in signal transduction. However, increased production of ROS is also involved in inducing pathophysiological changes such as apoptosis, cell cycle disruption, and necrosis. For this reason, induction of ROS-mediated damage in cancer cells by pharmacological agents that either promote ROS generation or disable the cellular antioxidant system is considered a potential therapeutic strategy for preferentially killing cancer cells[1].

Relation of tea ingestion to salivary redox and flow rate in healthy subjects

The biochemistry of human saliva can be altered by food intake.The benefits of tea drinking were extensively studied but the influence of tea ingestion on human saliva has not been revealed.The work aimed to investigate the immediate and delayed effect of vine tea,oolong tea and black tea intake on certain salivary biochemistry and flow rate.The saliva samples of healthy subjects were collected before,after and 30 min after tea ingestion.The chemical compositions and antioxidant capacity of tea samples were analyzed to correlate with salivary parameters.Principal component analysis indicated that the effects of vine tea consumption were dominated by increasing salivary flow rate(SFR),production rate of total protein(TPC),thiol(SH),malondialdehyde,catalase activity and antioxidant capacity(FRAP)in saliva.The antioxidant profile of studied tea samples(FRAP,polyphenols,flavonoids)was positively correlated with salivary SFR,TPC,SH and FRAP but negatively correlated with salivary uric acid concentration in saliva.

High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation

High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1.

How Schisandrae Fructus Benefits the Body: Mechanisms in Traditional Chinese Medicine and Modern Medicine

Schisandrae chinensis Fructus (SF) is a commonly used herb in Traditional Chinese Medicine (TCM). According to TCM theory, SF can invigorate Qi in the liver and other visceral organs through the meridian system. Furthermore, the liver’s pivotal role in regulating the functions of various visceral organs helps explain how SF can promote holistic health benefits. The main active ingredient of SF, schisandrin B (Sch B), has been found to improve mitochondrial ATP production and enhance glutathione redox status in multiple organs. This could account for the overall protective effects of Sch B on organs. Due to its stronger impact on liver function, the positive influence of Sch B on different organs may be facilitated by signal molecules originating from the liver.

Changes of the glutathione redox system during the weaning transition in piglets, in relation to small intestinal morphology and barrier function

Background: Weaning is known to result in barrier dysfunction and villus atrophy in the immediate post-weaning phase, and the magnitude of these responses is hypothesized to correlate with changes in the glutathione(GSH)redox system. Therefore, these parameters were simultaneously measured throughout the weaning phase, in piglets differing in birth weight category and weaning age, as these pre-weaning factors are important determinants for the weaning transition. Low birth weight(LBW) and normal birth weight(NBW) littermates were assigned to one of three weaning treatments;i.e. weaning at 3 weeks of age(3 w), weaning at 4 weeks of age(4 w) and removal from the sow at 3 d of age and fed a milk replacer until weaning at 3 weeks of age(3 d3 w). For each of these treatments, six LBW and six NBW piglets were euthanized at 0, 2, 5, 12 or 28 d post-weaning piglets, adding up 180 piglets.Results: Weaning increased the glutathione peroxidase activity on d 5 post-weaning in plasma, and duodenal and jejunal mucosa. Small intestinal glutathione-S-transferase activity gradually increased until d 12 post-weaning, and this was combined with a progressive rise of mucosal GSH up till d 12 post-weaning. Oxidation of the GSH redox status(GSH/GSSG Eh) was only observed in the small intestinal mucosa of 3 d3 w weaned piglets at d 5 postweaning. These piglets also demonstrated increased fluorescein isothiocyanate dextran(FD4) and horseradish peroxidase fluxes in the duodenum and distal jejunum during the experiment, and specifically demonstrated increased FD4 fluxes at d 2 to d 5 post-weaning. On the other hand, profound villus atrophy was observed during the weaning transition for all weaning treatments. Finally, LBW and NBW piglets did not demonstrate notable differences in GSH redox status, small intestinal barrier function and histo-morphology throughout the experiment.Conclusion: Although moderate changes in the GSH redox system were observed upon weaning, the GSH redox status remained at a steady state level in 3 w and 4 w weaned piglets and was therefore not associated with weaning induced villus atrophy. Conversely, 3 d3 w weaned piglets demonstrated GSH redox imbalance in the small intestinal mucosa, and this co-occurred with a temporal malfunction of their intestinal barrier function.

Red onion extract(Allium cepa L.)supplementation improves redox balance in oxidatively stressed rats

Onions,consumed worldwide,are a good source of dietary phytochemicals with proven antioxidant properties.Catechin and quercetin are the most common and widely consumed flavonoids.The present study aimed to investigate the possible protective effect of onion extract as well as flavonoids(catechin and quercetin)on rats subjected to oxidative stress by mercuric chloride(HgCl2)treatment.Experiments were conducted on rat erythrocytes,which are a good model system to study oxidative stress.Results show that the oxidative stress induced by HgCl2 in Wistar rats resulted in substantially increased erythrocyte lipid peroxidation and higher activity of red cell plasma membrane redox system(PMRS)along with corresponding decrease in the intracellular reduced glutathione and antioxidant activity.Onion extract supplementation significantly(P<0.05)attenuated these adverse effects of HgCl2.Flavonoid supplementation resulted in a slightly higher antioxidant response compared to onion extract.We conclude that supplementation of these flavonoids results in normalization of erythrocyte PMRS activity which provides onion(rich in quercetin),a novel mechanism to exert its antioxidant effect against HgCl2-induced oxidative stress in rat erythrocytes in vivo.©2013 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved.

Groundwater Level Effect on Redox Potential, on Cadmium Uptake and Yield of Soybean

In this greenhouse experiment, we investigated the effects of two constant groundwater levels: 10 cm groundwater level (GW-10) and 40 cm groundwater level (GW-40) and one change groundwater level, which was 40-10-40 cm (GW-40-10-40) on Cadmium (Cd) uptake and seed yield of Soybean plant in Cd contaminated soils (1.57 mg·kg-1). The experimental soil layer was made with gravel layer (14 cm), non-polluted soil (15 cm) and polluted soil (25 cm). The redox potential of every soil layer was measured from sowing to harvesting. The soil layer (10 – 40 cm) of GW-10 was always in reduction condition and that of GW-40 was always in oxidation condition. First 50 days of GW 40-10-40 were in oxidation and next 50 days in reduction and final 20 days again returned in oxidation condition. Soybean seed Cd concentration was significantly highest in GW-40-10-40 (1.16 ± 0.13 mg·kg-1) and lowest in GW-40 (0.81 ± 0.12 mg·kg-1). Cd concentration of stem was found significantly higher in GW-40 (1.7 ± 0.2 mg·kg-1) than GW-10 (0.91 ± 0.08 mg·kg-1) and GW-40-10-40 (1.28 ± 0.13 mg·kg-1). There was no significant difference in root Cd concentration among these 3 treatments. Main stem height of soybean plant and 100 seed weight of GW-40 were significantly higher than those of GW-10. The result revealed that, soil redox condition is an important factor for Cd uptake in soybean plant and seed yield of soybean. This study will help to manage the farming process more appropriately with the aim of minimizing uptake of Cd and other toxic metals in grain crops.

养殖长茎葡萄蕨藻(Caulerpa lentillifera)污损微藻群落结构与水体pH和Eh变化的相关性

为探讨水体的pH和氧化还原电位(Eh)与长茎葡萄蕨藻(Caulerpa lentillifera)养殖过程中污损微藻群落变化的相关性,在养殖池中安装酸度计和氧化还原电位仪,在夹苗板处放置微藻附着试验塑料挂板45块,试验90 d。每隔10 d提取5板,合并分析微藻种群结构,记录同期pH和Eh。结果表明,共检出硅藻门4属4种,蓝藻门4属4种;pH前50 d呈上升趋势,后40 d趋于稳定,Eh在90 d内一直呈上升趋势;在前期pH和Eh较低的状态下硅藻类种群为优势群落,后期较高时则以蓝藻类种群为优势群落。pH和Eh与污损微藻种群结构具有显著相关性,与蓝藻种群呈正相关,与硅藻种群呈负相关。

强化栽培条件下干湿灌溉对水稻生长的影响

在中国水稻研究所试验场研究了强化栽培条件下干湿灌溉对水稻生长的影响。结果表明：在强化栽培条件下采取干湿灌溉处理，在返青期、分蘖期、孕穗期和抽穗开花期比对照分别节水1．4％、12．4％、9．0％和11．2％；水分生产效率达0．93kg/m^3，比CK处理提高34．2％；干4～5d之后，再复水4～5d，土壤氧化还原电位循环变化，有利于提高土壤氧化还原电位，改善土壤的通气状况，提高根系活力，促进大穗，穗粒数明显增加，单产平均提高6．9％。

氧化还原电位和pH对生物滞留系统硝酸盐异化还原为氨作用的影响

试验以模拟生物滞留系统为研究对象,运用^(15)N同位素示踪技术研究土壤不同氧化还原电位(Eh)和p H条件下硝酸盐异化还原为氨(DNRA)作用对氮的去除效果。结果表明:在土壤Eh为225~100 m V、0^-120 m V和-225^-340 m V条件下,随着Eh的降低,硝酸盐异化还原为氨(DNRA)作用增强;生物滞留系统中同时存在反硝化反应和DNRA作用,在0^-120 m V区间,更有利于反硝化作用的发生;在-225^-340 m V区间,更有利于DNRA作用的发生;生物滞留系统土壤p H为5~7的条件下,DNRA作用效果随着p H的增加而增强;在p H为7~9时,DNRA作用效果随着p H的增加而减弱;表明DNRA作用易在中性偏碱性的环境下发生。

禾本科秸秆对植烟土氧化还原电位和营养效率的影响研究

选择3种植烟土壤(酸性、中性及偏碱性),设置禾本科秸秆与化肥配施,单施化肥等处理,通过对植烟土壤根区氧化还原电位(Eh)的原位测定,研究施用有机物对植烟土壤根区Eh、烤烟吸收矿质营养效率和烟叶质量等的影响。结果表明:配施秸秆能提高土壤根区的Eh,显著增加烤烟的营养效率吸收以及增加烟叶的产量和产值。

砂岩型铀矿床层间氧化带前锋区稀有元素富集机制

在深入研究砂岩型铀矿床层间氧化带各地球化学分带中铀及其伴生元素的分布规律时,发现一些单价态(不变价)元素也常常富集在层间氧化带前锋区,其典型代表是钪(Sc)、钇(Y)和稀土元素(REE)等。作者在综合分析前苏联众多砂岩型铀矿床各地球化学分带中各种元素大量测试数据的基础上,论述了层间氧化带前锋区Eh值和pH值的变化规律以及它们所导致的变价元素(U、Se、Mo和V)和不变价元素(Sc、Y和REE)的分布规律和富集机制。实际上,层间氧化带前锋区既是氧化-还原电位(Eh值)又是酸碱度(pH值)的急剧变化区,两者大致同步消长。层间氧化带前锋区有两类地球化学障:单纯的还原障和还原-碱性综合障。两种地球化学障的发育与强度取决于原始未氧化岩石中硫化物、有机质和碳酸盐的含量。

HPLC法同时检测血浆中半胱氨酸/胱氨酸和还原型谷胱甘肽/氧化型谷胱甘肽的氧化还原电势

目的本研究拟探讨一种比较敏感、能同时检测血浆中半胱氨酸(cysteine,Cys)/胱氨酸(cystine,CySS)和还原型谷胱甘肽(reduced glutathione,GSH)/氧化型谷胱甘肽(oxidized glutathione,GSSG)含量及相应的氧化还原电势(Eh)的方法。方法取大鼠全血,去除红细胞及蛋白后用碘乙酸封闭自由的巯基,通过丹磺酰氯衍生化后,利用高效液相色谱(highperformance liquid chromatography,HPLC)进行分离,根据能斯特方程计算相应的氧化还原电势。结果本方法可同时测定体内GSH/GSSG和Cys/CySS的含量及相应的氧化还原电势,灵敏度高、准确性强。结论本研究提供了一种简便有效地检测血浆中氧化还原状态的方法,可能为诊断与氧化应激相关疾病提供新的依据。

Investigation of the redox status in H22 hepatocellular carcinoma xenografts treated by a novel anticancer drug-ethaselen

We investigated the redox status of H22 hepatocellular carcinoma xenografts treated with various doses of ethaselen, a novel anticancer drug targeting thioredoxin reductase （TrxR）. The concentrations of low molecular weight antioxidant g!utathione （GSH） and malondialdehyde （MDA）, a product of lipid peroxidation, as well as the activities of important antioxidant enzymes were measured for elucidating the redox status of H22 tumor tissues. We found that the decreased GSH level, decreased thioredoxin reductase and superoxide dismutase （SOD） activities as well as increased MDA content were closely related to the tumor growth inhibition and ethaselen doses. Glutathione peroxidase （GPx） and glutathinne reductase （GR） activities are also affected by ethaselen treatment. However, the catalase （CAT） activity remains unchanged. Finally, we studied the relationship of tumor growth inhibition caused by ethaselen with these redox factors. This study showed that ethaselen could elevate the oxidative stress to suppress the H22 tumor growth in mice model.

Synchronous detection of glutathione/hydrogen peroxide for monitoring redox status in vivo with a ratiometric upconverting nanoprobe

Cellular redox status presents broad implications with diverse physiological and pathological processes. Simultaneous detection of both the oxidative and reductive species of redox couples, especially the most representative pair glutathione/hydrogen peroxide (GSH/H2O2), is crucial to accurately map the cellular redox status. However, it still remains challenging to synchronously detect GSH/H2O2 in vivo due to lack of a reliable measuring tool. Herein, a ratiometric nanoprobe (UCNP-TB) possessing simultaneous delectability of GSH/H2O2 is established based on a multi-spectral upconverti ng nano phosphor (UCNP-OA) as the lumin esce nee res onance energy tran sfer (LRET) donor and two dye molecules as the acceptors, including a GSH-sensitive dye (TCG) and a H2O2-sensitive dye (BCH). With the as-prepared UCNP-TB, real-time and synchronous monitoring the variation of GSH and H2O2 in vitro and in living mice can be achieved using the ratio of the upcon versi on lumin esce nee (UCL) at 540 and 650 nm to that at 800 nm as the detecti on sign al, respectively, providi ng highly inhere nt reliability of the sensing results by self-calibrati on. Moreover, the nan oprobe is capable of mappi ng the redox status within the drug-resista nt tumor and the drug-induced hepatotoxic liver via ratiometric UCL imaging. Thus, this nan oprobe would provide a reliable tool to elucidate the redox state in vivo.

水分调控对水稻根际土壤及产量的影响

通过盆栽试验,分析了不同水分调控处理下水稻产量及水稻根际土壤氧化还原电位(Eh)和微生物的变化。结果表明,干湿交替处理下土壤Eh升高,提高了土壤的通气性,细菌、放线菌活性和数量都呈增加趋势,促进水稻根系生长;其中W2处理水稻各生育期的干物质累积量、收获指数、产量及其构成(穗粒数、结实率和千粒质量)均最高。W2处理是获得高产稳产的最佳水分调控方式。

Dietary N-carbamylglutamate and L-arginine supplementation improves redox status and suppresses apoptosis in the colon of intrauterine growth-retarded suckling lambs

Previous studies have revealed that dietary N-carbamylglutamate(NCG)or L-arginine(Arg)improves small intestinal integrity and immune function in suckling Hu lambs that have experienced intrauterine growth retardation(IUGR).Whether these nutrients alter redox status and apoptosis in the colon of IUGR lambs is still unknown.This study,therefore,aimed at investigating whether dietary supplementation of Arg or NCG alters colonic redox status,apoptosis and endoplasmic reticulum(ER)stress and the underlying mechanism of these alterations in IUGR suckling Hu lambs.Forty-eight 7-d old Hu lambs,including 12 with normal birth weight(4.25±0.14 kg)and 36 with IUGR(3.01±0.12 kg),were assigned to 4 treatment groups(n=12 each;6 males and 6 females)for 3 weeks.The treatment groups were control(CON),IUGR,IUGR+Arg and IUGR+NCG.Relative to IUGR lambs,superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)content,as well as proliferation index,were higher(P<0.05)whereas reactive oxygen species(ROS),malondialdehyde(MDA)levels and apoptotic cell numbers were lower(P<0.05)in colonic tissue for both IUGR+Arg and NCG lambs.Both m RNA and protein levels of C/EBP homologous protein 10(CHOP10),B-cell lymphoma/leukaemia 2(Bcl-2)-associated X protein(Bax),apoptosis antigen 1(Fas),activating transcription factor 6(ATF6),caspase 3,and glucose-regulated protein 78(GRP78)were lower(P<0.05)while glutathione peroxidase 1(GPx1),Bcl-2 and catalase(CAT)levels were higher(P<0.05)in colonic tissue for IUGR+Arg and IUGR+NCG lambs compared with IUGR lambs.Based on our results,dietary NCG or Arg supplementation can improve colonic redox status and suppress apoptosis via death receptor-dependent,mitochondrial and ER stress pathways in IUGR suckling lambs.

Elevated peroxidative glutathione redox status in atherosclerotic patients with increased thickness of carotid intima media

Background Atherosclerosis is a chronic inflammatory disease. Accumulated evidences suggest a deep involvement of oxidative damage in the development of atherosclerosis, but little is discussed over the relationship between plasma glutathione redox status as the most important intrinsic antioxidant defensive mechanism and the atherosclerosis. Methods A total of 132 patients suspected with atherosclerosis were assigned to three groups by high frequency ultrasonic examination of the carotid artery. With the thickness of intima of the carotid artery as an index of degree of atherosclerosis progression, 56 were included in plaque-forming group （A）, 42 in carotid artery intima-thickening group （B）, and 34 in normal carotid artery intima-thickness group （C）. All patients were subjected to the measurement of plasma glutathione （GSH） （reduced form GSH and oxidized form GSSG）, nicotinamide adenine dinucleotide phosphate （NADP） （reduced form NADPH and oxidized form NADP^＋）, oxidized low density lipoprotein （oxLDL）, and malondialdehyde （MDA） The GSH/GSSG and NADPH/NADP^＋ redox potentials were calculated according to the Nernst equation, and their correlation with intima thickness and oxLDL was analyzed. Results With the thickening of artery intima （from group C to A）, GSH concentration and the ratio of GSH/GSSG gradually reduced, and GSSG and GSH/GSSG redox potential gradually increased （more positive） （P 〈0.05）. The NADPH and NADPH/NADP^＋ redox status also showed similar but milder changes. The products of oxidative stress oxLDL and MDA increased significantly along with the thickening of artery intima （P 〈0.05）. The analysis of the relationship between GSH/GSSG redox potential, intima thickness, and oxLDL showed positive correlations （P 〈0.05）. The plasma GSH/GSSG redox status was positively correlated with the intima thickness of the carotid artery and the oxidized injury of LDL. The redox status shifted to oxidizing direction along with the intima thickening and plaque-forming. Conclusion Elevated peroxidative glutathione redox status was deeply implicated in atherosclerosis progressing, and it may be a sensitive and reliable index for monitoring oxidative status in atherosclerosis.