Prenatal antioxidant-enriched and pro-oxidant-contained food, IL4 and IL13 pathway genes, and cord blood IgE.

Prenatal oxidative balance might influence cord blood IgE (cIgE) levels. We aimed to explore if certain prenatal dietary sources of antioxidants and pro-oxidants are associated with cIgE elevation and if they interact with IL4 and IL13 pathway genes. A structured questionnaire was completed during the third trimester of pregnancy for 1107 full-term newborns. Surveyed antioxidant-enriched food included fish, shellfish, and fruit, whereas surveyed pro-oxidant-contained food included fried fish sticks and canned fish. Cord blood was collected for measuring cIgE levels and genotyping IL13 rs1800925, rs20541, rs848, IL4 rs2243250, and STAT6 rs324011. Fairly lean fish consumption showed protection against cIgE elevation (odds ratio [OR] 0.66; 95% CI 0.49-0.90) in the whole sample, while daily fruit (OR 0.46; 95% CI 0.27-0.79) and ≥ monthly canned fish (OR 2.81; 95% CI 1.24-6.36) exhibited associations only in genetically susceptible babies. A prenatal food protective index, comprising any fairly lean fish, daily fruit, and the absence of any canned fish, exerted dose-response protection against cIgE elevation in babies carrying the IL13 rs20541 GA or AA genotype (P for trend < 0.0001; P for interaction = 0.004). We concluded that prenatal antioxidant-enriched and pro-oxidant-contained food consumption may influence cIgE, especially in genetically susceptible babies.

ROS-Induced Oxidative Damage and Mitochondrial Dysfunction Mediated by Inhibition of SIRT3 in Cultured Cochlear Cells.

Sensorineural hearing loss (SNHL) is one of the most common causes of disability worldwide. Previous evidence suggests that reactive oxygen species (ROS) may play an important role in the occurrence and development of SNHL, while its mechanism remains unclear. We cultured dissected organs of Corti in medium containing different concentrations (0, 0.25, 0.5, 0.75, 1, and 1.25 mM) of hydrogen peroxide (H2O2) and established a four-concentration model of 0, 0.5, 0.75, and 1 mM to study different degrees of damage. We examined ROS-induced mitochondrial damage and the role of sirtuin 3 (SIRT3). Our results revealed that the number of ribbon synapses and hair cells appeared significantly concentration-dependent decrease with exposure to H2O2. Outer hair cells (OHCs) and inner hair cells (IHCs) began to be lost, and activation of apoptosis of hair cells (HCs) was observed at 0.75 mM and 1 mM H2O2, respectively. In contrast with the control group, the accumulation of ROS was significantly higher, and the mitochondrial membrane potential (MMP) was lower in the H2O2-treated groups. Furthermore, the expression of SIRT3, FOXO3A, and SOD2 proteins declined, except for an initial elevation of SIRT3 between 0 and 0.75 mM H2O2. Administration of the selective SIRT3 inhibitor 3-(1H-1,2,3-triazol-4-yl) pyridine resulted in increased damage to the cochlea, including loss of ribbon synapses and hair cells, apoptosis of hair cells, more production of ROS, and reduced mitochondrial membrane potential. Thoroughly, our results highlight that ROS-induced mitochondrial oxidative damage drives hair cell degeneration and apoptosis. Furthermore, SIRT3 is crucial for preserving mitochondrial function and protecting the cochlea from oxidative damage and may represent a possible therapeutic target for SNHL.

An In Situ FTIR Study of DBD Plasma Parameters for Accelerated Germination of Arabidopsis thaliana Seeds.

Current agricultural practices are not sustainable; however, the non-thermal plasma treatment of seeds may be an eco-friendly alternative to alter macroscopic plant growth parameters. Despite numerous successful results of plasma-seed treatments reported in the literature, the plasma-treatment parameters required to improve plant growth remain elusive due to the plethora of physical, chemical, and biological variables. In this study, we investigate the optimal conditions in our surface dielectric barrier discharge (SDBD) setup, using a parametric study, and attempt to understand relevant species in the plasma treatment using in situ Fourier transform infrared (FTIR) absorption spectroscopy. Our results suggest that treatment time and voltage are key parameters for accelerated germination; however, no clear conclusion on causative agents can be drawn.

Redox nanomedicine ameliorates chronic kidney disease (CKD) by mitochondrial reconditioning in mice.

Targeting reactive oxygen species (ROS) while maintaining cellular redox signaling is crucial in the development of redox medicine as the origin of several prevailing diseases including chronic kidney disease (CKD) is linked to ROS imbalance and associated mitochondrial dysfunction. Here, we have shown that a potential nanomedicine comprising of Mn3O4 nanoparticles duly functionalized with biocompatible ligand citrate (C-Mn3O4 NPs) can maintain cellular redox balance in an animal model of oxidative injury. We developed a cisplatin-induced CKD model in C57BL/6j mice with severe mitochondrial dysfunction and oxidative distress leading to the pathogenesis. Four weeks of treatment with C-Mn3O4 NPs restored renal function, preserved normal kidney architecture, ameliorated overexpression of pro-inflammatory cytokines, and arrested glomerulosclerosis and interstitial fibrosis. A detailed study involving human embryonic kidney (HEK 293) cells and isolated mitochondria from experimental animals revealed that the molecular mechanism behind the pharmacological action of the nanomedicine involves protection of structural and functional integrity of mitochondria from oxidative damage, subsequent reduction in intracellular ROS, and maintenance of cellular redox homeostasis. To the best of our knowledge, such studies that efficiently treated a multifaceted disease like CKD using a biocompatible redox nanomedicine are sparse in the literature. Successful clinical translation of this nanomedicine may open a new avenue in redox-mediated therapeutics of several other diseases (e.g., diabetic nephropathy, neurodegeneration, and cardiovascular disease) where oxidative distress plays a central role in pathogenesis.

Antioxidant Supplements versus Health Benefits of Brief/Intermittent Exposure to Potentially Toxic Physical or Chemical Agents.

Although antioxidants can act locally to react with an oxidant, oral administration of "antioxidants" is quite useless in treating oxidative stress in tissues. Furthermore, it does not make sense to consider a vitamin as an antioxidant, but vitamin B3 leads to the in vivo formation of compounds that are essential for reducing this stress. A rigorous treatment of the subject indicates that to deal with oxidative stress, the most direct approach is to enhance the innate antioxidant mechanisms. The question is whether this is possible through daily activities. Diets can contain the necessary components for these mechanisms or may induce the expression of the genes involved in them. Another possibility is that pro-oxidant molecules in food increase the sensitivity and power of the detoxification pathways. This option is based on well-known DNA repair mechanisms after exposure to radiation (even from the Sun), or strong evidence of induction of antioxidant capacity after exposure to powerful pro-oxidants such as H2O2. More experimental work is required to test whether some molecules in food can increase the expression of antioxidant enzymes and/or improve antioxidant mechanisms. Identifying effective molecules to achieve such antioxidant power is critical to the food and nutraceutical industries. The potential of diet-based interventions to combat oxidative stress must be viewed from a new perspective.

Photosynthesis is sensitive to nitric oxide and respiration sensitive to hydrogen peroxide: Studies with pea mesophyll protoplasts.

Reports on the effect of nitric oxide (NO) or reactive oxygen species (ROS) on photosynthesis and respiration in leaf tissues are intriguing; therefore, the effects of exogenous addition of sodium nitroprusside (SNP, releases NO) or H2O2 on the photosynthetic O2 evolution and respiratory O2 uptake by mesophyll protoplasts in pea (Pisum sativum) were evaluated in the present study. Low concentrations of SNP or H2O2 were used to minimize nonspecific effects. The effects of NO or H2O2 on respiration and photosynthesis were different. The presence of NO decreased the rate of photosynthesis but caused a marginal stimulation of dark respiration. Conversely, externally administered H2O2 drastically decreased the rate of respiration but only slightly decreased photosynthesis. The PS I activity was more sensitive to NO than PS II. On the other hand, 100 µM H2O2 had no effect on the photochemical reactions of either PS I or PS II. The sensitivity of photosynthesis to antimycin A or SHAM (reflecting the interplay between chloroplasts and mitochondria) was not affected by NO. By contrast, H2O2 markedly decreased the sensitivity of photosynthesis to antimycin A and SHAM. It can be concluded that chloroplasts are the primary targets of NO, while mitochondria are the primary targets of ROS in plant cells. We propose that H2O2 can be an important signal to modulate the crosstalk between chloroplasts and mitochondria.

Programmed ROS/CO-releasing nanomedicine for synergetic chemodynamic-gas therapy of cancer.

BACKGROUND: To improve the outcome of cancer treatment, the combination of multiple therapy models has proved to be effective and promising. Gas therapy (GT) and chemodynamic therapy (CDT), mainly targeting the mitochondrion and nucleus, respectively, are two emerging strategy for anti-cancer. The development of novel nanomedicine for integrating these new therapy models is greatly significant and highly desired. METHODS: A new nanomedicine is programmed by successive encapsulation of MnO2 nanoparticles and iron carbonyl (FeCO) into mesoporous silica nanoparticle. By decoding the nanomedicine, acidity in the lysosome drives MnO2 to generate ROS, ·OH among which further triggers the decomposition of FeCO into CO, realizing the effective combination of chemodynamic therapy with gas therapy for the first time. RESULTS: Acidity in the TEM drives MnO2 to generate ROS, ∙OH among which further triggers the decomposition of FeCO into CO, realizing the effective combination of CDT and CDGT. The co-released ROS and CO do damage to DNA and mitochondria of various cancer cells, respectively. The mitochondrial damage can effectively cut off the ATP source required for DNA repair, causing a synergetic anti-cancer effect in vitro and in vivo. CONCLUSIONS: The combination of CDT and CDGT causing a synergetic anti-cancer effect in vitro and in vivo. The proposed therapy concept and nanomedicine designing strategy might open a new window for engineering high-performance anti-cancer nanomedicine.

Mesoporous Silica-Based Nanoparticles for Light-Actuated Biomedical Applications via Near-Infrared Two-Photon Absorption.

In this review, we highlight the design of nanomaterials for two-photon excitation, in order to treat tumors with a high accuracy. Indeed two-photon excitation allows remote control of the nanoparticles with a spatio-temporal resolution. The nanomaterials are based on mesoporous silica-organosilica nanoparticles including core-shell systems. The therapeutic treatments include drug delivery, photodynamic therapy, gene silencing, and their combinations. At first, the nanosystems designed for two-photon-triggered cytotoxic drug delivery are reviewed. Then the nanomaterials prepared for two-photon photodynamic therapy and reactive oxygen species delivery are discussed. Finally, the nanosystems combining drug delivery or gene silencing with two-photon photodynamic therapy are presented. Due to the rapid progresses concerning two-photon-excited nanomaterials and the interest of near-infrared light to treat deep tumors, we believe this technology could be of high interest for the personalized medicine of the future.

The use of reduced glutathione (GSH) as antioxidant for cryopreserved sperm in dogs / O uso da glutationa reduzida (GSH) como antioxidante na criopreservação seminal em cães

The aim of this study was to evaluate the effect of supplementation with different concentrations of reduced glutathione GSH (0; 5; 7.5; 10mM) in the extender for cryopreservation in dogs with evaluations performed after glycerolization (chilled) and thawing (thawed). For this purpose, we used 8 dogs and two semen collections were performed in a weekly interval, totaling 16 semen samples. The sperm were analyzed by automatic sperm motility (CASA) and flow cytometry analysis of mitochondrial potential (JC1 dye) and membrane/acrosome integrity (FITC-PI dyes). We evaluated subjectively the membrane and acrosome integrity, mitochondrial activity and DNA integrity. Seminal plasma was evaluated for lipid peroxidation (TBARS concentration). Chilled and thawed samples supplemented with 7.5 and 10mM of GSH had lower percentage of sperm with high (DAB - Class I) and medium (DAB - Class II) mitochondrial activity. And 10mM of GSH had higher percentage of low mitochondrial activity (DAB - Class III). Moreover, thawed samples of 10mM of GSH had high DNA fragmentation rates. Probably by a reductive stress effect on mitochondria which lead to an increase in reactive oxygen species, and a mitochondrial malfunction.(AU)

O objetivo deste estudo foi avaliar o efeito da suplementação com diferentes concentrações de glutationa reduzida (GSH - 0; 5; 7,5; 10mM) para criopreservação em cães com avaliações realizadas após glicerolização (refrigeração) e descongelação. Para tal, foram utilizados oito cães e foram realizadas duas coletas de sêmen em intervalo semanal, totalizando 16 amostras de sêmen. Foram avaliadas a motilidade espermática computadorizada (CASA) e a análise de citometria de fluxo do potencial mitocondrial (sonda JC-1) e integridade da membrana/acrossomal (sonda FITC-PI). Subjetivamente foi avaliada a integridade da membrana plasmática e do acrossomal, atividade mitocondrial e integridade do DNA. O plasma seminal foi avaliado quanto à peroxidação lipídica (concentração de TBARS). As amostras refrigeradas e descongeladas suplementadas com 7,5 e 10mM de GSH apresentaram menor porcentagem de espermatozoides com alta atividade mitocondrial (DAB - Classe I) e média (DAB - Classe II). Na concentração de 10mM de GSH, apresentaram maior porcentagem de baixa atividade mitocondrial (DAB - Classe III). Além disso, amostras descongeladas de 10mM de GSH apresentaram taxas de fragmentação de DNA elevadas, provavelmente por efeito de estresse redutivo sobre as mitocôndrias que elevam as espécies reativas de oxigênio e disfunção mitocondrial.(AU)

Negative correlation between presence of reactive oxygen species and Sperm Motility Index in whole semen samples of infertile males / Correlación negativa entre la presencia de especies reactivas del oxígeno y el índice de movilidad espermática en muestras completas de semen de varones estériles

Objective. To investigate the relationship between the Sperm Motility Index and the presence of reactive oxygen species in semen. Methods. We retrospectively analyzed Sperm Motility Index measured by the Sperm Quality Analyzer and reactive oxygen species levels in 92 semen samples of infertile male patients who visited the Ebina Ladies’ Clinic between September 2011 and June 2012. Using the same semen samples, we also analyzed 8 sperm parameters measured by computer-assisted semen analysis and validated the relationship with the Sperm Motility Index. Results. The presence of reactive oxygen species in semen was positive in 19 samples and negative in 73 samples. In the reactive oxygen species-positive group, there was a significant negative correlation between the logarithm of reactive oxygen species level and Sperm Motility Index (p = 0.039). Conclusions. This is the first study to find a significant negative correlation between Sperm Motility Index and reactive oxygen species level. This result indicates that the presence of reactive oxygen species in semen may inhibit the fertilization ability of spermatazoa as measured by the Sperm Motility Index (AU)

Objetivo. Investigar la relación entre el índice de movilidad espermática y la presencia de especies reactivas del oxígeno en el semen. Métodos. Analizamos retrospectivamente el índice de movilidad espermática medido por el analizador de calidad del esperma y los niveles de especies reactivas del oxígeno en 92 muestras de semen de varones estériles que visitaron Ebina Ladies’ Clinic entre septiembre de 2011 y junio de 2012. Con las mismas muestras de semen también analizamos 8 parámetros del esperma medidos mediante un análisis de semen asistido por ordenador y validamos la relación con el índice de movilidad espermática. Resultados. La presencia de especies reactivas del oxígeno en el semen dio positivo en 19 muestras y negativo en 73. En el grupo positivo para especies reactivas del oxígeno hubo una correlación negativa significativa entre el logaritmo de nivel de especies reactivas del oxígeno y el índice de movilidad espermática (p = 0,039). Conclusiones. Este es el primer estudio que encuentra una correlación negativa significativa entre el índice de movilidad espermática y el nivel de especies reactivas del oxígeno. Este resultado indica que la presencia de especies reactivas del oxígeno en el semen podría inhibir la capacidad de fecundación de los espermatozoides según la medición del índice de movilidad espermática (AU)

Pro-oxidant and pro-apoptotic activity of polyphenol extract from Annurca apple and its underlying mechanisms in human breast cancer cells.

Among nutraceuticals, polyphenols represent the most intriguing and studied class of compounds that can be therapeutics for a large spectrum of the most common diseases, including cancer. Although polyphenols are well known as potent antioxidants, a pro-oxidant effect has been associated with a pro-apoptotic function of these compounds in various types of tumor cells. Annurca apple, a southern Italian variety, is characterized by an extremely high content of polyphenols and displays a stronger antioxidant activity compared with other varieties. In the present study we explored the antiproliferative effect of Annurca apple polyphenol extract (APE) in human breast cancer MCF-7 cells and we investigated the underlying mechanisms. Results showed that at 500 µM catechin equivalent (EqC) APE acts as a pro-oxidant increasing thiobarbituric acid-reactive species cell content of approximately 6-fold more than the untreated cells. We found that APE strongly inhibits the proliferation of MCF-7 cells by inducing G2/M cell cycle arrest and apoptosis. Immunoblot analysis demonstrated that APE treatment increases the levels of p53 and p21, downregulates the expression of the cell cycle regulatory protein cyclin D1, and inhibits ERK1/2 phosphorylation. Moreover, APE treatment caused a marked increase of pro-apoptotic Bax/Bcl-2 ratio paralleled by caspase-9, -6, -7, and poly(ADP ribose) polymerase cleavage. Altogether our data indicate that APE, at elevated concentrations, acts as a potent pro-oxidant and antiproliferative agent able to downregulate ERK1/2 pathway leading to cell cycle inhibition and apoptosis and provides a rationale for its potential use in the development of novel therapeutics towards breast cancer.

Targeting Photochemical Scalpels or Lancets in the Photodynamic Therapy Field-The Photochemist's Role.

This review covers photochemical approaches aimed at supplementing surgical instruments with handheld photodynamic therapy (PDT) instruments. PDT is not widely used in hospitals, because of the laser equipment and expertise needed, and because insurance policies often do not cover the procedure. Accordingly, this review focuses on advances in photochemistry, photophysics, nanotechnology and miniaturization techniques that may likely inspire the use of handheld instruments in PDT. A takeaway point is that the advent of photochemical scalpels or lancets that deliver reactive oxygen species (ROS) on site may better equip medical practitioners and allow for eradication of tumors or infections in general. Specifically, the review is divided into several sections: sensitizer types, multiphoton and plasmonic topics, sensitizer delivery, light delivery, dosimetry, fiber optics and handheld implements in PDT.

Spotlight on the relevance of mtDNA in cancer

The potential role of the mitochondrial genome has recently attracted interest because of its high mutation frequency in tumors. Different aspects of mtDNA make it relevant for cancer‘s biology, such as it encodes a limited but essential number of genes for OXPHOS biogenesis, it is particularly susceptible to mutations, and its copy number can vary. Moreover, most ROS in mitochondria are produced by the electron transport chain. These characteristics place the mtDNA in the center of multiple signaling pathways, known as mitochondrial retrograde signaling, which modifies numerous key processes in cancer. Cybrid studies support that mtDNA mutations are relevant and exert their effect through a modification of OXPHOS function and ROS production. However, there is still much controversy regarding the clinical relevance of mtDNA mutations. New studies should focus more on OXPHOS dysfunction associated with a specific mutational signature rather than the presence of mutations in the mtDNA (AU)

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Tumor cell specific and lysosome-targeted delivery of nitric oxide for enhanced photodynamic therapy triggered by 808 nm near-infrared light.

A novel cancer cell lysosome-targetable multifunctional NO-delivery nanoplatform (Lyso-Ru-NO@FA@C-TiO2) (1) was developed. It selectively targets folate-receptor overexpressed cancer cells and specifically locates within the lysosome organelle to which NO and reactive oxygen species are simultaneously released upon 808 nm NIR light irradiation. The dual-targeted nanoplatform (1) demonstrated the highest anticancer efficacy compared with nontargeted counterparts under NIR light sensitization.

Ants medicate to fight disease.

Parasites are ubiquitous, and the ability to defend against these is of paramount importance. One way to fight diseases is self-medication, which occurs when an organism consumes biologically active compounds to clear, inhibit, or alleviate disease symptoms. Here, we show for the first time that ants selectively consume harmful substances (reactive oxygen species, ROS) upon exposure to a fungal pathogen, yet avoid these in the absence of infection. This increased intake of ROS, while harmful to healthy ants, leads to higher survival of exposed ants. The fact that ingestion of this substance carries a fitness cost in the absence of pathogens rules out compensatory diet choice as the mechanism, and provides evidence that social insects medicate themselves against fungal infection, using a substance that carries a fitness cost to uninfected individuals.

Targeting increased copper levels in diethylnitrosamine induced hepatocellular carcinoma cells in rats by epigallocatechin-3-gallate.

We have earlier elucidated a pathway for the anticancer action of plant polyphenolic compounds against malignant cells involving mobilisation of endogenous copper ions and the consequent prooxidant action. To further confirm our hypothesis in vivo, we induced hepatocellular carcinoma (HCC) in rats by diethylnitrosamine (DEN). We show that in such carcinoma cells, there is a progressive elevation in copper levels at various intervals after DEN administration. Concurrently with increasing copper levels, epigallocatechin-3-gallate (EGCG; a potent anticancer plant polyphenol found in green tea) mediated DNA breakage in malignant cells is also increased. The cell membrane permeable copper chelator neocuproine inhibited the EGCG-mediated cellular DNA degradation, whereas the membrane impermeable chelator bathocuproine was ineffective. Iron and zinc specific chelators desferoxamine mesylate and histidine, respectively, were also ineffective in inhibiting EGCG mediated DNA breakage. Through the use of specific scavengers, the mechanism of DNA breakage was determined to be mediated by reactive oxygen species. In summary, we provide an in vivo evidence of accumulating copper in hepatocellular carcinoma that is targeted by EGCG, leading to its anticancer role in a prooxidant manner. Our findings confirm a novel mechanism of anticancer activity of EGCG in particular and plant derived nutraceuticals in general.

Reactive oxygen species and vascular remodeling in cardiovascular diseases / Especies reactivas de oxígeno y remodelado vascular en enfermedades cardiovasculares

Reactive oxygen species (ROS) are reactive derivatives of O2 metabolism produced by all types of vascular cells. ROS play an important role in both physiological and pathological situations by acting as intracellular signaling molecules which regulate vascular function and structure. Accordingly, oxidative stress is implicated among other processes in inflammation, hypertrophy, migration, growth/apoptosis and extracellular matrix protein turnover which are important processes involved in vascular remodeling in cardiovascular diseases. In the cardiovascular system, the major source of ROS is the NADPH oxidase family of enzymes composed by seven members where NOX-1 and NOX-4 are the main isoforms in vascular smooth muscle cells. This review highlights the importance of NOX-derived ROS in vascular biology and focuses on the potential role of oxidative stress in vascular remodeling

Las especies reactivas de oxígeno son derivados reactivos del metabolismo del O2 producido por todos los tipos celulares a nivel vascular. Las especies reactivas de oxígeno juegan un papel importante en situaciones tanto fisiológicas como patológicas mediante su actuación como moléculas de señalización intracelular que regulan la función y estructura vascular. De esta manera, el estrés oxidativo está implicado, entre otros procesos, en la inflamación, hipertrofia, migración, proliferación/apoptosis y reciclaje de proteínas de matriz extracelular, los cuales son procesos importantes implicados en el remodelado vascular durante enfermedades cardiovasculares. En el sistema cardiovascular, la mayor fuente de especies reactivas de oxígeno es la familia de enzimas NADPH oxidase formadas por siete miembros donde NOX-1 y NOX-4 son las principales isoformas en células musculares lisas vasculares. Esta revisión destaca la importancia de las especies reactivas de oxígeno derivadas de NOX en la biología vascular y se centra en el papel potencial del estrés oxidativo en el remodelado vascular

Nitration of protein without allergenic potential triggers modulation of antioxidant response in type II pneumocytes.

Inhalation of nitrogen and reactive oxygen species (ROS) is known to induce lung inflammation, which is prevented by enzymatic and nonenzymatic antioxidant systems. These agents form nitrated allergens that were shown to enhance allergenicity. The aim of this study was to examine the influence of nitrated proteins on inflammation and antioxidant status of the lung. Ovalbumin (OVA) in nitrated form (nOVA) was intraperitoneally (ip) injected in mice for sensitization and in nitrated or unmodified form for challenge to induce allergic bronchial inflammation. To study the allergen potential of unrelated protein and verify cross-reactivity, nitrated and unmodified keyhole limpet hemocyanin (nKLH, KLH) was used for challenge. Challenge with OVA or nOVA reduced lung function and increased eosinophilia and protein content in bronchoalveolar lavage fluid (BALF). Challenge with nitrated or native OVA or KLH elevated glutathione (GSH) ratio in type II pneumocytes. Reduced mRNA expression of glutathione peroxidase (GPX) 3, glutathione reductase (GR), superoxide dismutase (SOD) 2, and catalase (CAT) was most prominent after challenge with nitrated OVA and nitrated KLH, respectively. Challenge with nOVA enhanced SOD1 mRNA reduction. Immunostaining of GPX 3 and SOD2 increased after challenge with OVA or nOVA, while reactivity of GR and reactivity of SOD2 were reduced after challenge with KLH or nKLH. SOD1 immunostaining was diminished after challenge with nonnitrated OVA or KLH. CAT immunoreaction was similar in all groups. Nitrated proteins without allergenic potential triggered mRNA reduction of antioxidants in type II cells after sensitization with a nitrated allergen but did not induce bronchial inflammation.

Ascorbic acid modulation of iron homeostasis and lysosomal function in trabecular meshwork cells.

PURPOSE: To investigate the antioxidant properties and biological functions of ascorbic acid (AA) on trabecular meshwork (TM) cells. METHODS: Primary cultures of porcine TM cells were supplemented for 10 days with increasing concentrations of AA. Antioxidant properties against cytotoxic effect of H2O2 were evaluated by monitoring cell viability. Redox-active iron was quantified using calcein-AM. Intracellular reactive oxygen species (iROS) production was quantified using H2DCFDA. Ferritin and cathepsin protein levels were analyzed by Western blot. Autophagy was evaluated by monitoring lipidation of LC3-I to LC3-II. Lysosomal proteolysis and cathepsins activities were quantified using specific fluorogenic substrates. RESULTS: AA exerts a dual effect against oxidative stress in TM cells, acting as an anti-oxidant or a pro-oxidant, depending on the concentration used. The pro-oxidant effect of AA was mediated by free intracellular iron and correlated with increased protein levels of ferritin and elevated iROS. In contrast, antioxidant properties correlated with lower ferritin and basal iROS content. Ascorbic acid supplementation also caused induction of autophagy, as well as increased lysosomal proteolysis, with the latter resulting from higher proteolytic activation of lysosomal cathepsins in treated cultures. CONCLUSIONS: Our results suggest that the reported decrease of AA levels in plasma and aqueous humor can compromise lysosomal degradation in the outflow pathway cells with aging and contribute to the pathogenesis of glaucoma. Restoration of physiological levels of vitamin C inside the cells might improve their ability to degrade proteins within the lysosomal compartment and recover tissue function.

Thioredoxin interacting protein and its association with clinical outcome in gastro-oesophageal adenocarcinoma.

The overall prognosis for operable gastro-oesophageal adenocarcinoma remains poor and therefore neoadjuvant chemotherapy has become the standard of care, in addition to radical surgery. Certain anticancer agents (e.g. anthracyclines and cisplatin) generate damaging reactive oxygen species as by-products of their mechanism of action. Drug effectiveness can therefore depend upon the presence of cellular redox buffering systems that are often deregulated in cancer. The expression of the redox protein, thioredoxin interacting protein, was assessed in gastro-oesophageal adenocarcinomas. Thioredoxin interacting protein expression was assessed using conventional immunohistochemistry on a tissue microarray of 140 adenocarcinoma patients treated by primary surgery alone and 88 operable cases treated with neoadjuvant chemotherapy. In the primary surgery cases, high thioredoxin interacting protein expression associated with a lack of lymph node involvement (p=0.005), no perineural invasion (p=0.030) and well/moderate tumour differentiation (p=0.033). In the neoadjuvant tumours, high thioredoxin interacting protein expression was an independent marker for improved disease specific survival (p=0.002) especially in cases with anthracycline-based regimes (p=0.008). This study highlights the potential of thioredoxin interacting protein as a biomarker for response in neoadjuvant treated gastro-oesophageal adenocarcinoma and may represent a useful therapeutic target due to its association with tumour progression.