Oxidative Stress Markers in Sputum

GC-MS and GC-MS/MS measurement of malondialdehyde (MDA) in clinical studies: Pre-analytical and clinical considerations

Malondialdehyde (MDA; 1,3-propanedial, OHC-CH2-CHO) is one of the most frequently measured biomarkers of oxidative stress in plasma and serum. L-Arginine (Arg) is the substrate of nitric oxide synthases (NOS), which convert L-arginine to nitric oxide (NO) and L-citrulline. The Arg/NO pathway comprises several members, including the endogenous NOS-activity inhibitor asymmetric dimethylarginine (ADMA) and its major metabolite dimethyl amine (DMA), and nitrite and nitrate, the major NO metabolites. Reliable measurement of MDA and members of the Arg/NO pathway in plasma, serum, urine and in other biological samples, such as saliva and cerebrospinal fluid, is highly challenging both for analytical and pre-analytical reasons. In our group, we use validated gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) methods for the quantitative determination in clinical studies of MDA as a biomarker of oxidative stress, and various Arg/NO metabolites that describe the status of this pathway. Here, the importance of pre-analytical issues, which has emerged from the use of GC-MS and GC-MS/MS in clinico-pharmacological studies, is discussed. Paradigmatically, two studies on the long-term oral administration of L-arginine dihydrochloride to patients suffering from peripheral arterial occlusive disease (PAOD) or coronary artery disease (CAD) were considered. Pre-analytical issues that were addressed include blood sampling, plasma or serum storage, study design (notably in long-term studies), and the alternative of measuring MDA in human urine.

The Role of Oxidative Stress and Antioxidants in Cardiovascular Comorbidities in COPD

Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in disease pathomechanisms. Unbalance between oxidants and antioxidant defense mechanisms amplifies the local inflammatory processes, worsens cardiovascular health, and contributes to COPD-related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures, with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced, with some suggestions for further research in the field.

Effect of breathing exercises on oxidative stress biomarkers in humans: A systematic review and meta-analysis

Background

Breathing exercises improve oxidative stress in healthy young adults and patients with diabetes, hypertension, and chronic obstructive pulmonary disease. Furthermore, the mechanism of respiratory intervention is controversial. Therefore, in this meta-analysis, we aimed to systematically evaluate the effects of breathing exercises on oxidative stress biomarkers in humans and provide evidence for the clinical application of breathing exercises.

Methods

The Embase, PubMed, Cochrane Library, Web of Science, CNKI, and WANFANG databases were searched for studies about the effects of breathing exercises on human oxidative stress levels, with no restraints regarding time, race, or language. The experimental group included various breathing exercises, and the outcome index included malondialdehyde, superoxide dismutase, and glutathione, nitric oxide, vitamin C, or total antioxidant capacity levels from a randomized controlled trial. Data were extracted by more than two authors and reviewed by one author.

Results

Ten studies were included from five countries. Data from patients with no disease, chronic obstructive pulmonary disease, hypertension, or diabetes were included. Participants who performed breathing exercises had greater changes in the included biomarkers than those who did not, suggesting that these biomarkers can be used to evaluate oxidative stress after respiratory interventions.

Conclusion

Breathing exercises increased SOD and GSH activities and decreased MDA content.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022337119, identifier CRD42022337119.

Alleviating the unwanted effects of oxidative stress on Aβ clearance: a review of related concepts and strategies for the development of computational modelling

Treatment for Alzheimer's disease (AD) can be more effective in the early stages. Although we do not completely understand the aetiology of the early stages of AD, potential pathological factors (amyloid beta [Aβ] and tau) and other co-factors have been identified as causes of AD, which may indicate some of the mechanism at work in the early stages of AD. Today, one of the primary techniques used to help delay or prevent AD in the early stages involves alleviating the unwanted effects of oxidative stress on Aβ clearance. 4-Hydroxynonenal (HNE), a product of lipid peroxidation caused by oxidative stress, plays a key role in the adduction of the degrading proteases. This HNE employs a mechanism which decreases catalytic activity. This process ultimately impairs Aβ clearance. The degradation of HNE-modified proteins helps to alleviate the unwanted effects of oxidative stress. Having a clear understanding of the mechanisms associated with the degradation of the HNE-modified proteins is essential for the development of strategies and for alleviating the unwanted effects of oxidative stress. The strategies which could be employed to decrease the effects of oxidative stress include enhancing antioxidant activity, as well as the use of nanozymes and/or specific inhibitors. One area which shows promise in reducing oxidative stress is protein design. However, more research is needed to improve the effectiveness and accuracy of this technique. This paper discusses the interplay of potential pathological factors and AD. In particular, it focuses on the effect of oxidative stress on the expression of the Aβ-degrading proteases through adduction of the degrading proteases caused by HNE. The paper also elucidates other strategies that can be used to alleviate the unwanted effects of oxidative stress on Aβ clearance. To improve the effectiveness and accuracy of protein design, we explain the application of quantum mechanical/molecular mechanical approach.

Airway Smooth Muscle Regulated by Oxidative Stress in COPD

Since COPD is a heterogeneous disease, a specific anti-inflammatory therapy for this disease has not been established yet. Oxidative stress is recognized as a major predisposing factor to COPD related inflammatory responses, resulting in pathological features of small airway fibrosis and emphysema. However, little is known about effects of oxidative stress on airway smooth muscle. Cigarette smoke increases intracellular Ca²⁺ concentration and enhances response to muscarinic agonists in human airway smooth muscle. Cigarette smoke also enhances proliferation of these cells with altered mitochondrial protein. Hydrogen peroxide and 8-isoprostans are increased in the exhaled breath condensate in COPD. These endogenous oxidants cause contraction of tracheal smooth muscle with Ca²⁺ dynamics through Ca²⁺ channels and with Ca²⁺ sensitization through Rho-kinase. TNF-α and growth factors potentiate proliferation of these cells by synthesis of ROS. Oxidative stress can alter the function of airway smooth muscle through Ca²⁺ signaling. These phenotype changes are associated with manifestations (dyspnea, wheezing) and pathophysiology (airflow limitation, airway remodeling, airway hyperresponsiveness). Therefore, airway smooth muscle is a therapeutic target against COPD; oxidative stress should be included in treatable traits for COPD to advance precision medicine. Research into Ca²⁺ signaling related to ROS may contribute to the development of a novel agent for COPD.

Phthalate Exposure and Oxidative/Nitrosative Stress in Childhood Asthma: A Nested Case-Control Study with Propensity Score Matching

Whether low-dose phthalate exposure triggers asthma among children, and its underlying mechanisms, remain debatable. Here, we evaluated the individual and mixed effects of low-dose phthalate exposure on children with asthma and five (oxidative/nitrosative stress/lipid peroxidation) mechanistic biomarkers—8-hydroxy-2′-deoxyguanosine (8-OHdG), 8-nitroguanine (8-NO₂Gua), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-isoprostaglandin F2α (8-isoPF2α), and malondialdehyde (MDA)—using a propensity score-matched case-control study (case vs. control = 41 vs. 111). The median monobenzyl phthalate (MBzP) concentrations in the case group were significantly higher than those in the control group (3.94 vs. 2.52 ng/mL, p = 0.02), indicating that dust could be an important source. After adjustment for confounders, the associations of high monomethyl phthalate (MMP) (75th percentile) with 8-NO₂Gua (adjusted odds ratio (aOR): 2.66, 95% confidence interval (CI): 1.03–6.92) and 8-isoPF2α (aOR: 4.04, 95% CI: 1.51–10.8) and the associations of mono-iso-butyl phthalate (MiBP) with 8-isoPF2α (aOR: 2.96, 95% CI: 1.13–7.79) were observed. Weighted quantile sum regression revealed that MBzP contributed more than half of the association (56.8%), followed by MiBP (26.6%) and mono-iso-nonyl phthalate (MiNP) (8.77%). Our findings supported the adjuvant effect of phthalates in enhancing the immune system response.

The Impact of Air Pollution on the Course of Cystic Fibrosis: A Review

Cystic fibrosis (CF) is a lethal and widespread autosomal recessive disorder affecting over 80,000 people worldwide. It is caused by mutations of the CFTR gene, which encodes an epithelial anion channel. CF is characterized by a great phenotypic variability which is currently not fully understood. Although CF is genetically determined, the course of the disease might also depend on multiple other factors. Air pollution, whose effects on health and contribution to respiratory diseases are well established, is one environmental factor suspected to modulate the disease severity and influence the lung phenotype of CF patients. This is of particular interest as pulmonary failure is the primary cause of death in CF. The present review discusses current knowledge on the impact of air pollution on CF pathogenesis and aims to explore the underlying cellular and biological mechanisms involved in these effects.

Astragaloside IV suppresses inflammatory response via suppression of NF-κB, and MAPK signalling in human bronchial epithelial cells

CONTEXT

Astragaloside IV isolated from Astragalus membranaceus (Fisch.), which was reported to have anti-tumor, anti-asthma, and suppressed cigarette smoke-induced lung inflammation in mice.

OBJECTIVES

This study investigated whether astragaloside IV reduced the expression of inflammatory mediators and oxidative stress in BEAS-2B cells.

METHODS

BEAS-2B cells treated with astragaloside IV, and then stimulated with TNF-α or TNF-α/IL-4. The levels of cytokine and chemokine were analysed with ELISA and real-time PCR.

RESULTS

Astragaloside IV significantly inhibited the levels of CCL5, MCP-1, IL-6 and IL-8. Astragaloside IV also reduced ICAM-1 expression for blocked THP-1 monocyte adhesion to BEAS-2B cells. Furthermore, astragaloside IV attenuated the phosphorylation of MAPK, and reduced the translocation of p65 into the nucleus. Astragaloside IV could increase the expression of HO-1 and Nrf2 for promoting the oxidant protective effect.

CONCLUSION

Aastragaloside IV has an anti-inflammatory and oxidative effect via regulated NF-κB, MAPK and HO-1/Nrf2 signalling pathways in human bronchial epithelial cells.

Stressed out - The role of oxidative stress in airway smooth muscle dysfunction in asthma and COPD

The airway smooth muscle (ASM) surrounding the airways is dysfunctional in both asthma and chronic obstructive pulmonary disease (COPD), exhibiting; increased contraction, increased mass, increased inflammatory mediator release and decreased corticosteroid responsiveness. Due to this dysfunction, ASM is a key contributor to symptoms in patients that remain symptomatic despite optimal provision of currently available treatments. There is a significant body of research investigating the effects of oxidative stress/ROS on ASM behaviour, falling into the following categories; cigarette smoke and associated compounds, air pollutants, aero-allergens, asthma and COPD relevant mediators, and the anti-oxidant Nrf2/HO-1 signalling pathway. However, despite a number of recent reviews addressing the role of oxidative stress/ROS in asthma and COPD, the potential contribution of oxidative stress/ROS-related ASM dysfunction to asthma and COPD pathophysiology has not been comprehensively reviewed. We provide a thorough review of studies that have used primary airway, bronchial or tracheal smooth muscle cells to investigate the role of oxidative stress/ROS in ASM dysfunction and consider how they could contribute to the pathophysiology of asthma and COPD. We summarise the current state of play with regards to clinical trials/development of agents targeting oxidative stress and associated limitations, and the adverse effects of oxidative stress on the efficacy of current therapies, with reference to ASM related studies where appropriate. We also identify limitations in the current knowledge of the role of oxidative stress/ROS in ASM dysfunction and identify areas for future research.

Incorporating Biomarkers in COPD Management: The Research Keeps Going

Globally, chronic obstructive pulmonary disease (COPD) remains a major cause of morbidity and mortality, having a significant socioeconomic effect. Several molecular mechanisms have been related to COPD including chronic inflammation, telomere shortening, and epigenetic modifications. Nowadays, there is an increasing need for novel therapeutic approaches for the management of COPD. These treatment strategies should be based on finding the source of acute exacerbation of COPD episodes and estimating the patient’s own risk. The use of biomarkers and the measurement of their levels in conjunction with COPD exacerbation risk and disease prognosis is considered an encouraging approach. Many types of COPD biomarkers have been identified which include blood protein biomarkers, cellular biomarkers, and protease enzymes. They have been isolated from different sources including peripheral blood, sputum, bronchoalveolar fluid, exhaled air, and genetic material. However, there is still not an exclusive biomarker that is used for the evaluation of COPD but rather a combination of them, and this is attributed to disease complexity. In this review, we summarize the clinical significance of COPD-related biomarkers, their association with disease outcomes, and COPD patients’ management. Finally, we depict the various samples that are used for identifying and measuring these biomarkers.

Alterations of serum and saliva oxidative markers in patients with bronchial asthma

BACKGROUNDS

The development of asthma is highly affected by exposure to exogenous and endogenous oxidative molecules, but the impact of this exposure on the pathophysiology of asthma has received little attention.

OBJECTIVES

Evaluating group of selective oxidative stress markers as a tool in the management of asthma disease.

METHODS

In comparison with matched healthy controls, levels of the oxidant and antioxidant markers: lipid peroxidation malondialdehyde (MDA), Total glutathione (tGSH), Uric acid (UA), Glutathione peroxidase (GPx), Catalase (CAT) superoxide dismutase (SOD), and Total antioxidant capacity (TAC) were assessed in serum and saliva of different asthma groups.

RESULTS

All oxidative markers in serum and saliva of asthma patients showed significant alterations from normal healthy controls (P < 0.05), except the salivary SOD (P = 0.441). Their levels in serum were significantly correlated with asthma severity (P < 0.05), and the distinguishing between childhood and adult asthma was significantly accomplished by GPx, SOD, TAC markers (P < 0.05). However, in patients with childhood asthma no significant differences were detected between the levels of GPx, CAT, UA, MDA in serum and saliva samples (P > 0.05).

CONCLUSION

Determination of the oxidative markers GPx, CAT, UA in serum or saliva can distinguish asthma from healthy states. The serum levels of UA and TAC are highly effective in monitoring asthma severity, while the salivary GPx, CAT, UA, MDA are beneficial in the management of childhood asthma. Discrimination of the age factor between asthma groups can be achieved by testing GPx, SOD, TAC in serum.

Ginsenoside Rg3 ameliorates allergic airway inflammation and oxidative stress in mice

Background

Ginsenoside Rg3, isolated from Panax ginseng, has anti-inflammatory and anti-tumor activities. It is known to reduce inflammation in acute lung injury in mice, and to reduce the expression of inflammatory cytokines and COX-2 in human asthmatic airway epithelium. In this study, we attempted to determine whether ginsenoside Rg3 inhibits airway inflammation, oxidative stress, and airway hyperresponsiveness (AHR) in the lungs of asthmatic mice. We also investigated its effects on oxidative stress and the inflammatory response in tracheal epithelial cells.

Methods

Asthma symptoms were induced in female BALB/c mice sensitized with ovalbumin (OVA). Mice were divided into five groups: normal controls, OVA-induced asthmatic controls, and asthmatic mice treated with ginsenoside Rg3 or prednisolone by intraperitoneal injection. Inflammatory BEAS-2B cells (human tracheal epithelial cells) treated with ginsenoside Rg3 to investigate its effects on inflammatory cytokines and oxidative responses.

Results

Ginsenoside Rg3 treatment significantly reduced eosinophil infiltration, oxidative responses, airway inflammation, and AHR in the lungs of asthmatic mice. Ginsenoside Rg3 reduced Th2 cytokine and chemokine levels in bronchoalveolar lavage fluids and lung. Inflammatory BEAS-2B cells treated with ginsenoside Rg3 reduced the eotaxin and pro-inflammatory cytokine expressions, and monocyte adherence to BEAS-2B cells was significantly reduced as a result of decreased ICAM-1 expression. Furthermore, ginsenoside Rg3 reduced the expression of reactive oxygen species in inflammatory BEAS-2B cells.

Conclusion

Ginsenoside Rg3 is a potential immunomodulator that can ameliorate pathological features of asthma by decreasing oxidative stress and inflammation

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Ginsenoside Rg3 reduced eosinophil infiltration, and airway hyperresponsiveness in the lungs of asthmatic mice.

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Ginsenoside Rg3 inhibited oxidative responses in the lungs.

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Ginsenoside Rg3 reduced the levels of Th2 cytokines in BALF and lung.

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Ginsenoside Rg3 inhibited monocyte cell adherence to tracheal epithelial cells.

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Ginsenoside Rg3 reduced the levels of pro-inflammatory cytokines in tracheal epithelial cells.

Rheological effects of hypertonic saline and sodium bicarbonate solutions on cystic fibrosis sputum in vitro

BACKGROUND

Cystic fibrosis (CF) is a life-threatening multiorgan genetic disease, particularly affecting the lungs, where recurrent infections are the main cause of reduced life expectancy. In CF, mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein impair transepithelial electrolyte and water transport, resulting in airway dehydration, and a thickening of the mucus associated with abnormal viscoelastic properties. Our aim was to develop a rheological method to assess the effects of hypertonic saline (NaCl) and NaHCO₃ on CF sputum viscoelasticity in vitro, and to identify the critical steps in sample preparation and in the rheological measurements.

METHODS

Sputum samples were mixed with hypertonic salt solutions in vitro in a ratio of either 10:4 or 10:1. Distilled water was applied as a reference treatment. The rheological properties of sputum from CF patients, and the effects of these in vitro treatments, were studied with a rheometer at constant frequency and strain, followed by frequency sweep tests, where storage modulus (G'), loss modulus (G″) and loss factor were determined.

RESULTS

We identified three distinct categories of sputum: (i) highly elastic (G' > 100,000 Pa), (ii) elastic (100,000 Pa > G' > 1000 Pa), and (iii) viscoelastic (G' < 1000). At the higher additive ratio (10:4), all of the added solutions were found to significantly reduce the gel strength of the sputum, but the most pronounced changes were observed with NaHCO₃ (p < 0.001). Samples with high elasticity exhibited the greatest changes while, for less elastic samples, a weakening of the gel structure was observed when they were treated with water or NaHCO₃, but not with NaCl. For the viscoelastic samples, the additives did not cause significant changes in the parameters. When the lower additive ratio (10:1) was used, the mean values of the rheological parameters usually decreased, but the changes were not statistically significant.

CONCLUSION

Based on the rheological properties of the initial sputum samples, we can predict with some confidence the treatment efficacy of each of the alternative additives. The marked differences between the three categories suggest that it is advisable to evaluate each sample individually using a rheological approach such as that described here.

Vitamin D Supplementation: Oxidative Stress Modulation in a Mouse Model of Ovalbumin-Induced Acute Asthmatic Airway Inflammation

Asthma oxidative stress disturbances seem to enable supplementary proinflammatory pathways, thus contributing to disease development and severity. The current study analyzed the impact of two types of oral vitamin D (VD) supplementation regimens on the redox balance using a murine model of acute ovalbumin-induced (OVA-induced) asthmatic inflammation. The experimental prevention group received a long-term daily dose of 50 µg/kg (total dose of 1300 µg/kg), whereas the rescue group underwent a short-term daily dose of 100 µg/kg (total dose of 400 µg/kg). The following oxidative stress parameters were analyzed in serum, bronchoalveolar lavage fluid (BALF) and lung tissue homogenate (LTH): total oxidative status, total antioxidant response, oxidative stress index, malondialdehyde and total thiols. Results showed that VD significantly reduced oxidative forces and increased the antioxidant capacity in the serum and LTH of treated mice. There was no statistically significant difference between the two types of VD supplementation. VD also exhibited an anti-inflammatory effect in all treated mice, reducing nitric oxide formation in serum and the expression of nuclear factor kappa B p65 in the lung. In conclusion, VD supplementation seems to exhibit a protective role in oxidative stress processes related to OVA-induced acute airway inflammation.

Fructose-1,6-bisphosphatase aggravates oxidative stress-induced apoptosis in asthma by suppressing the Nrf2 pathway

Asthma is a chronic airway disease that causes excessive inflammation, oxidative stress, mucus production and bronchial epithelial cell apoptosis. Fructose‐1,6‐bisphosphatase (Fbp1) is one of the rate‐limiting enzymes in gluconeogenesis and plays a critical role in several cancers. However, its role in inflammatory diseases, such as asthma, is unclear. Here, we examined the expression, function and mechanism of action of Fbp1 in asthma. Gene Expression Omnibus (GEO) data sets revealed that Fbp1 was overexpressed in a murine model of asthma and in interleukin (IL)‐4‐ or IL‐13‐stimulated bronchial epithelial cells. We confirmed the findings in an animal model as well as Beas‐2B and 16HBE cells. In vitro investigations revealed that silencing of Fbp1 reduced apoptosis and the proportion of cells in the G2/M phase, whereas overexpression led to increases. Fbp1 knock‐down inhibited oxidative stress by activating the nuclear factor erythroid 2‐related factor 2 (Nrf2) pathway, whereas Fbp1 overexpression aggravated oxidative stress by suppressingthe Nrf2 pathway. Moreover, the Nrf2 pathway inhibitor ML385 reversed the changes caused by Fbp1 inhibition in Beas‐2B and 16HBE cells. Collectively, our data indicate that Fbp1 aggravates oxidative stress‐induced apoptosis by suppressing Nrf2 signalling, substantiating its potential as a novel therapeutic target in asthma.

Nutritional Factors in Occupational Lung Disease

PURPOSE OF REVIEW

Lung diseases such as asthma and COPD are major public health issues and related to occupational exposures. While therapies to limit the development and progression of these diseases are limited, nutrition interventions could offer potential alternatives to mediate the inflammation associated with these diseases. This is a narrative review of the current state of relevant nutrients on inflammation and respiratory outcomes associated with occupational exposures.

RECENT FINDINGS

Relevant nutrients that have been investigated in recent years include omega-3 polyunsaturated fatty acids, zinc, vitamin D, dairy products, and antioxidants. These nutrients have demonstrated the potential to prevent or modify the adverse outcomes associated with occupational exposures, primarily in preclinical studies. Current therapies for respiratory consequences associated with occupational exposures are limited; therefore, addressing strategies for reducing inflammation is important in improving quality of life and limiting health care costs. More human studies are warranted to determine the effectiveness of nutrition as an intervention.

Uncovering the Role of Oxidative Imbalance in the Development and Progression of Bronchial Asthma

Asthma is a chronic inflammatory disease of the airways related to epithelial damage, bronchial hyperresponsiveness to contractile agents, tissue remodeling, and luminal narrowing. Currently, there are many data about the pathophysiology of asthma; however, a new aspect has emerged related to the influence of reactive oxygen and nitrogen species (ROS and RNS) on the origin of this disease. Several studies have shown that an imbalance between the production of ROS and RNS and the antioxidant enzymatic and nonenzymatic systems plays an important role in the pathogenesis of this disease. Considering this aspect, this study is aimed at gathering data from the scientific literature on the role of oxidative distress in the development of inflammatory airway and lung diseases, especially bronchial asthma. For that, articles related to these themes were selected from scientific databases, including human and animal studies. The main findings of this work showed that the respiratory system works as a highly propitious place for the formation of ROS and RNS, especially superoxide anion, hydrogen peroxide, and peroxynitrite, and the epithelial damage is reflected in an important loss of antioxidant defenses that, in turn, culminates in an imbalance and formation of inflammatory and contractile mediators, such as isoprostanes, changes in the activity of protein kinases, and activation of cell proliferation signalling pathways, such as the MAP kinase pathway. Thus, the oxidative imbalance appears as a promising path for future investigations as a therapeutic target for the treatment of asthmatic patients, especially those resistant to currently available therapies.

Preventive and therapeutic effect of anti-IL-17 in an experimental model of elastase-induced lung injury in C57Bl6 mice

Chronic obstructive pulmonary disease (COPD) is an important health care issue, and IL-17 can modulate inflammatory responses. We evaluated preventive and therapeutic effect of anti-interleukin (IL)-17 in a model of lung injury induced by elastase, using 32 male C57Bl6 mice, divided into 4 groups: SAL, ELASTASE CONTROL (EC), ELASTASE + PREVENTIVE ANTI-IL-17 (EP), and ELASTASE + THERAPEUTIC ANTI-IL-17 (ET). On the 29th day, animals were anesthetized with thiopental, tracheotomized, and placed on a ventilator to evaluate lung mechanical, exhaled nitric oxide (eNO), and total cells of bronchoalveolar lavage fluid was collected. We performed histological techniques, and linear mean intercept (Lm) was analyzed. Both treatments with anti-IL-17 decreased respiratory resistance and elastance, airway resistance, elastance of pulmonary parenchyma, eNO, and Lm compared with EC. There was reduction in total cells and macrophages in ET compared with EC. Both treatments decreased nuclear factor-кB, inducible nitric oxide synthase, matrix metalloproteinase (MMP)-9, MMP-12, transforming growth factor-β, tumor necrosis factor-α, neutrophils, IL-1β, isoprostane, and IL-17 in airways and alveolar septa; collagen fibers, decorin and lumican in airways; and elastic fibers and fibronectin in alveolar septa compared with EC. There was reduction of collagen fibers in alveolar septa and biglycan in airways in EP and a reduction of eNO synthase in airways in ET. In conclusion, both treatments with anti-IL-17 contributed to improve most of parameters evaluated in inflammation and extracellular matrix remodeling in this model of lung injury.

Markers of oxidative stress after three days of nanoTiO2 sunscreen use in humans: a pilot study

OBJECTIVE

Recent experimental studies point to a high reactivity of nanoparticles and the potential of sunscreens to penetrate the skin. We measured 20 markers of oxidative stress and inflammation to find out whether skin exposure to nanoTiO₂ sunscreen may elevate the level of the markers in exhaled breath condensate (EBC) and urine of exposed subjects, as was suggested by our earlier study.

METHODS

Six volunteers (3 males and 3 females), with a mean age of 48.0 ± 6.7 years, used commercial sunscreen for three days continuously. The first samples were collected before the test. The second samples were collected on day 4, before the sunscreen was washed off, and the third samples on day 11. The following biomarkers were measured: malondialdehyde, 4-hydroxy-trans-hexenal, 4-hydroxy-trans-nonenal, aldehydes C6-C12, 8-isoProstaglandin F2α, o-tyrosine, 3-chlorotyrosine, 3-nitrotyrosine, 8-hydroxy-2-deoxyguanosine, 8-hydroxyguanosine, 5-hydroxymethyl uracil, and leukotrienes B4, C4, D4, and E4, using liquid chromatography-electrospray ionisation-tandem mass spectrometry.

RESULTS

In the urine, 4-hydroxy-trans-hexenal was significantly higher in post-exposure sample 2, and the same trend was seen in all urinary markers. In EBC, no difference was seen between the mean values of 20 post-test markers as compared with pre-test samples.

CONCLUSION

This study suggests potential side effects of the sunscreen - borderline elevation of markers of oxidative stress/inflammation - which may relate to the absorption of the nanoTiO₂, and the non-significant difference may be explained by the small number of subjects. The effect was not seen in EBC, where nanoTiO₂ was not found. A larger study is needed, as according to our previous study, the beneficial effect of the sunscreen to suppress oxidative stress caused by UV radiation may be questioned.

Betaine effects against asthma-induced oxidative stress in the liver and kidney of mice

Allergic asthma is a chronic inflammatory airway disease concomitant with oxidative stress. The aim of this study was to evaluate the effects of betaine against asthma-induced oxidative stress in experimentally animal model. 32 BALB/C mice were divided into four equal groups as: control, asthma, prednisolone and betaine groups. 100 μl of the solution (Ova albumin (OVA, 400 μg and AL(OH)3 gel in 1 ml of phosphate buffer) was injected intraperitoneally to each mouse on days 0, 7, 14 and 21 and sensitized with OVA drop, three times a week from days 27 until 84 in asthma, prednisolone and betaine groups. Prednisolone (3 mg/kg) and betaine (1% of the total diet) were administered at day 27 to 84 as orally once daily and vehicle to controls and asthma group. Sera were collected for IgE detection and lung tissue was taken for histopathology assessment. Glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) activities, and glutathione content (GSH) as well as malondialdehyde (MDA) concentration as lipid peroxidation marker were also measured in the liver and kidney tissues. Pathological changes of the lung tissue were observed in the asthma and prednisolone groups. Prednisolone also caused significant increase level of anti-OVA IgE. The GPx activity increased significantly in the liver and kidney of asthmatic group when compared to the control and prednisolone groups. Liver MDA as lipid peroxidation marker was also significantly higher in the prednisolone-treated mice when compared to the other groups. Although the CAT and SOD activities as well as GSH content increased in the betaine and prednisolone-treated mice, these enhancements were not statically significant. Predinsolone as first choice in asthma treatment showed some oxidative properties. In contrast, betaine improved airway inflammation of lung tissue which may be associated with the antioxidant properties of betaine. This study provides a potential promising effect of betaine for treatment of asthma in future studies.

Protective effects of catalpol on mitochondria of hepatocytes in cholestatic liver injury

Cholestasis, which is caused by the obstruction of bile flow, can lead to rapid organ injury, cell apoptosis and necrosis of hepatocytes, and may eventually develop into fibrosis and cirrhosis. Oxidative stress and mitochondrial dysfunction are the key pathogenic signs of hepatic cholestasis. Catalpol has pharmacological activities, including antioxidative and anti-inflammatory effects, and may relieve mitochondrial damage and restore mitochondrial membrane potential. However, the potential roles and mechanisms of catalpol in cholestasis-induced liver injury are not clear. In the present study, liver function-related indexes were measured in the serum of mice by commercial kits. In addition, levels of serum inflammatory factors were detected by ELISA. Hematoxylin and eosin staining was performed to observe histopathological changes, and mitochondrial membrane potential was detected using JC-1 staining. Mitochondrial adenosine triphosphate (ATP), reactive oxygen species (ROS) and malondialdehyde levels were determined using a luciferase reporter kit, flow cytometry and a thiobarbituric acid reactive substance assay kit, respectively. Western blotting was performed to detect the expression levels of apoptosis-related proteins in liver tissues. The findings revealed that catalpol reduced liver damage caused by cholestasis, improved the mitochondrial membrane potential, and increased the ATP content and glutathione content of cholestasis model mice. Moreover, catalpol also reduced the ROS level, inhibited lipid peroxidation, and regulated oxidative stress and apoptotic protein expression. Thus, the present study preliminarily confirmed that catalpol can reduce liver injury in a mouse model of cholestasis through inhibiting oxidative stress and enhancing mitochondrial membrane potential.

Potential Therapeutic Role of Dietary Supplementation with Spirulina platensis on the Erectile Function of Obese Rats Fed a Hypercaloric Diet

Spirulina platensis, an important source of bioactive compounds, is a multicellular, filamentous cyanobacterium rich in high-quality proteins, vitamins, minerals, and antioxidants. Due to its nutrient composition, the alga is considered a complete food and is recognized for its anti-inflammatory, antioxidant, antiobesity, and reproprotective effects. All of which are important for prevention and treatment of organic and metabolic disorders such as obesity and erectile dysfunction. The aim of this study was to investigate the modulatory role of Spirulina platensis food supplementation and the mechanisms of action involved in reversing the damage caused by a hypercaloric diet on the erectile function of rats. The animals were divided into a standard diet group (SD, n = 5); a hypercaloric diet group (HCD, n = 5); a hypercaloric diet group supplemented with S. platensis at doses of 25 (HCD+SP25, n = 5), 50 (HCD+SP50, n = 5), and 100 mg/kg (HCD+SP100, n = 5); and a hypercaloric diet group subsequently fed a standard diet (HCD+SD, n = 5). In the rats fed a hypercaloric diet, dietary supplementation with S. platensis effectively increased the number of erections while decreasing latency to initiate penile erection. Additionally, S. platensis increases NO bioavailability, reduces inflammation by reducing the release of contractile prostanoids, enhances the relaxation effect promoted by acetylcholine (ACh), restores contractile reactivity damage and cavernous relaxation, reduces reactive oxygen species (ROS), and increases cavernous total antioxidant capacity (TAC). Food supplementation with S. platensis thus restores erectile function in obese rats, reduces production of contractile prostanoids, reduces oxidative stress, and increases NO bioavailability. Food supplementation with S. platensis thus emerges as a promising new therapeutic alternative for the treatment of erectile dysfunction as induced by obesity.

Importance of superoxide dismutases A and M for protection of Staphylococcus aureus in the oxidative stressful environment of cystic fibrosis airways

Staphylococcus aureus is one of the earliest pathogens that persists the airways of cystic fibrosis (CF) patients and contributes to increased inflammation and decreased lung function. In contrast to other staphylococci, S. aureus possesses two superoxide dismutases (SODs), SodA and SodM, with SodM being unique to S. aureus. Both SODs arm S. aureus for its fight against oxidative stress, a by-product of inflammatory reactions. Despite complex investigations, it is still unclear if both enzymes are crucial for the special pathogenicity of S. aureus. To investigate the role of both SODs during staphylococcal persistence in CF airways, we analysed survival and gene expression of S. aureus CF isolates and laboratory strains in different CF-related in vitro and ex vivo settings. Bacteria located in inflammatory and oxidised CF sputum transcribed high levels of sodA and sodM. Especially expression values of sodM were remarkably higher in CF sputum than in bacterial in vitro cultures. Interestingly, also S. aureus located in airway epithelial cells expressed elevated transcript numbers of both SODs, indicating that S. aureus is exposed to oxidative stress at various sites within CF airways. Both enzymes promoted survival of S. aureus during polymorphonuclear leukocyte killing and seem to act compensatory, thereby giving evidence that the interwoven interaction of SodA and SodM contributes to S. aureus virulence and facilitates S. aureus persistence within CF airways.

Oxidative Stress Attenuates TLR3 Responsiveness and Impairs Anti-viral Mechanisms in Bronchial Epithelial Cells From COPD and Asthma Patients

COPD and asthma exacerbations are commonly triggered by rhinovirus infection. Potentially promoting exacerbations, impaired anti-viral signaling and attenuated viral clearance have been observed in diseased bronchial epithelium. Oxidative stress is a feature of inflammation in asthma and COPD and is prominent during exacerbations. It is not known whether oxidative stress affects the anti-viral signaling capacity. Bronchial epithelial cells from asthmatic and COPD donors were infected with rhinovirus or treated with the oxidative stressor H₂O₂ followed by exposure to the synthetic viral replication intermediate poly(I:C). Poly(I:C) was used to ascertain a constant infection-like burden. Gene and protein levels of antioxidants as well as anti-viral responses were measured 3 and 24 h post poly(I:C) exposure. Rhinovirus infection and poly(I:C) stimulation induced protein levels of the antioxidants SOD1 and SOD2. In asthmatic bronchial epithelial cells pre-treatment with H₂O₂ dose-dependently decreased the antioxidant response to poly(I:C), suggesting exaggerated oxidative stress. Further, poly(I:C)-induced IFNβ gene expression was reduced after pre-treatment with H₂O₂. This epithelial effect was associated with a reduced expression of the pattern recognition receptors RIG-I, MDA5 and TLR3 both on gene and protein level. Pre-treatment with H₂O₂ did not alter antioxidant responses in COPD bronchial epithelial cells and, more modestly than in asthma, reduced poly(I:C)-induced IFNβ gene expression. Knockdown of TLR3 but not RIG-I/MDA5 abrogated impairment of poly(I:C)-induced IFNβ gene expression by H₂O₂. We developed a method by which we could demonstrate that oxidative stress impairs anti-viral signaling in bronchial epithelial cells from asthmatic and COPD patients, most pronounced in asthma. The impairment apparently reflects reduced responsiveness of TLR3. These present findings shed light on molecular mechanisms potentially causing reduced interferon responses to rhinovirus infection at exacerbations in asthma and COPD. Together, our findings suggest a possible self-perpetuating vicious cycle underlying recurrent exacerbations, leading to an impaired anti-viral response, which in turn leads to viral-induced exacerbations, causing more airway inflammation.

Mitochondrial Function in Peripheral Blood Mononuclear Cells (PBMC) Is Enhanced, Together with Increased Reactive Oxygen Species, in Severe Asthmatic Patients in Exacerbation

Asthma is a chronic inflammatory lung syndrome with an increasing prevalence and a rare but significant risk of death. Its pathophysiology is complex, and therefore we investigated at the systemic level a potential implication of oxidative stress and of peripheral blood mononuclear cells’ (PBMC) mitochondrial function. Twenty severe asthmatic patients with severe exacerbation (GINA 4–5) and 20 healthy volunteers participated at the study. Mitochondrial respiratory chain complexes activities using different substrates and reactive oxygen species (ROS) production were determined in both groups by high-resolution respirometry and electronic paramagnetic resonance, respectively. Healthy PBMC were also incubated with a pool of plasma of severe asthmatics or healthy controls. Mitochondrial respiratory chain complexes activity (+52.45%, p = 0.015 for V_ADP) and ROS production (+34.3%, p = 0.02) were increased in asthmatic patients. Increased ROS did not originate mainly from mitochondria. Plasma of severe asthmatics significantly increased healthy PBMC mitochondrial dioxygen consumption (+56.8%, p = 0.031). In conclusion, such asthma endotype, characterized by increased PMBCs mitochondrial oxidative capacity and ROS production likely related to a plasma constituent, may reflect activation of the immune system. Further studies are needed to determine whether increased PBMC mitochondrial respiration might have protective effects, opening thus new therapeutic approaches.

Protective Effects of Licochalcone A Improve Airway Hyper-Responsiveness and Oxidative Stress in a Mouse Model of Asthma

Licochalcone A was isolated from Glycyrrhiza uralensis and previously reported to have antitumor and anti-inflammatory effects. Licochalcone A has also been found to inhibit the levels of Th2-associated cytokines in the bronchoalveolar lavage fluid (BALF) of asthmatic mice. However, the molecular mechanism underlying airway inflammation and how licochalcone A regulates oxidative stress in asthmatic mice are elusive. In this study, we investigated whether licochalcone A could attenuate inflammatory and oxidative responses in tracheal epithelial cells, and whether it could ameliorate oxidative stress and airway inflammation in asthmatic mice. Inflammatory human tracheal epithelial (BEAS-2B) cells were treated with licochalcone A to evaluate oxidative responses and inflammatory cytokine levels. In addition, BALB/c mice were sensitized with ovalbumin (OVA) and injected intraperitoneally with licochalcone A (5 or 10 mg/kg). Licochalcone A significantly inhibited reactive oxygen species, eotaxin, and proinflammatory cytokines in BEAS-2B cells. Licochalcone A also decreased intercellular adhesion molecule 1 levels in inflammatory BEAS-2B cells, blocking monocyte cell adherence. We also found that licochalcone A significantly decreased oxidative responses, reduced malondialdehyde levels, and increased glutathione levels in the lungs of OVA-sensitized mice. Furthermore, licochalcone A decreased airway hyper-responsiveness, eosinophil infiltration, and Th2 cytokine production in the BALF. These findings suggest that licochalcone A alleviates oxidative stress, inflammation, and pathological changes by inhibiting Th2-associated cytokines in asthmatic mice and human tracheal epithelial cells. Thus, licochalcone A demonstrated therapeutic potential for improving asthma.

Cystic Fibrosis and Pseudomonas aeruginosa: the Host-Microbe Interface

In human pathophysiology, the clash between microbial infection and host immunity contributes to multiple diseases. Cystic fibrosis (CF) is a classical example of this phenomenon, wherein a dysfunctional, hyperinflammatory immune response combined with chronic pulmonary infections wreak havoc upon the airway, leading to a disease course of substantial morbidity and shortened life span. Pseudomonas aeruginosa is an opportunistic pathogen that commonly infects the CF lung, promoting an accelerated decline of pulmonary function. Importantly, P. aeruginosa exhibits significant resistance to innate immune effectors and to antibiotics, in part, by expressing specific virulence factors (e.g., antioxidants and exopolysaccharides) and by acquiring adaptive mutations during chronic infection. In an effort to review our current understanding of the host-pathogen interface driving CF pulmonary disease, we discuss (i) the progression of disease within the primitive CF lung, specifically focusing on the role of host versus bacterial factors; (ii) critical, neutrophil-derived innate immune effectors that are implicated in CF pulmonary disease, including reactive oxygen species (ROS) and antimicrobial peptides (e.g., LL-37); (iii) P. aeruginosa virulence factors and adaptive mutations that enable evasion of the host response; and (iv) ongoing work examining the distribution and colocalization of host and bacterial factors within distinct anatomical niches of the CF lung.

Elimination of bacterial DNA during RNA isolation from sputum: Bashing bead vortexing is preferable over prolonged DNase treatment

Sputum often contains large amounts of contaminating bacterial DNA that, if not eliminated during RNA isolation, may interfere with gene expression studies. During RNA isolation only repeated DNase treatment can effectively remove contaminating bacterial DNA from samples, but this compromises RNA quality. In this study we tested alternative methods to facilitate the removal of DNA and improve the quality of RNA obtained. Sputum samples obtained from patients with chronic obstructive pulmonary disease were processed with dithiothreitol and subjected to various RNA isolation methods, yet with modified protocols. Modifications included prolonged DNase treatment or vortexing of sputum cells in the presence of beads prior to RNA isolation. Bacterial DNA contamination was tested by PCR using universal bacterial primers, while RNA quality was assessed by real-time PCR using GAPDH primers for amplicons of different length. We found that the RNeasy Plus Mini kit equipped with the gDNA eliminator spin column was able to completely eliminate bacterial DNA, if sputum cells were lysed in the presence of bashing beads. Notably, compared with the standard protocol, the modified procedure yielded better quality RNA as well, as indicated by improved threshold profiles of qPCR. Bead vortexing of cells was less effective when combined with other RNA isolation methods, and the repeated DNase treatment needed to completely remove contaminating DNA from the samples reduced the quality of RNA markedly. Bead vortexing in combination with certain RNA extraction methods greatly facilitates the isolation of sputum RNA that is free of contaminating bacterial DNA, and is suitable for downstream applications.

Monitoring Antioxidant Enzyme Activity during Exacerbations of Chronic Obstructive Pulmonary Disease

Superoxide dismutases (SODs) and catalase (CAT) have been implicated as major antioxidant enzymes of the human lungs. In this study, we investigated whether activities of these enzymes are altered in the airways of patients hospitalized with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). SOD and CAT activities were measured in the sputum, exhaled breath condensate, and serum of 36 COPD patients experiencing a severe exacerbation. Measurements were performed using colorimetric assays in samples collected at the time of hospital admission and at the time of hospital discharge following treatment of AECOPD. For comparison, antioxidants were also assessed in 24 stable COPD patients and 23 healthy control subjects. SOD and CAT activities in sputum were significantly increased in patients with AECOPD compared to those with stable disease (SOD: 0.142 [0.053-0.81] vs. 0.038 [0.002-0.146] U/mL, p < 0.01; CAT: 48.7 [18.7-72.6] vs. 10.2 [2.9-40.6] nmol/min/mL, p < 0.05), while treatment of exacerbation led to a decrease in enzyme activities (SOD: 0.094 [0.046-0.45] U/mL, p < 0.05; CAT: 28.0 [7.3-60.4] nmol/min/mL, p < 0.005). No changes were observed in the serum (p > 0.05). Both SOD and CAT activities significantly correlated with sputum neutrophil and lymphocyte cell counts in patients with AECOPD. Moreover, SOD and CAT values correlated with each other and also with sputum malondialdehyde, an established marker for oxidative stress. Our data demonstrate that sputum antioxidant activity is elevated during COPD exacerbation and suggest that activation of SODs and CAT is an integral part of the human defense mechanism against the increased oxidant production associated with AECOPD.

Markers of Oxidative Stress in the Exhaled Breath Condensate of Workers Handling Nanocomposites

Researchers in nanocomposite processing may inhale a variety of chemical agents, including nanoparticles. This study investigated airway oxidative stress status in the exhaled breath condensate (EBC). Nineteen employees (42.4 ± 11.4 y/o), working in nanocomposites research for 18.0 ± 10.3 years were examined pre-shift and post-shift on a random workday, together with nineteen controls (45.5 ± 11.7 y/o). Panels of oxidative stress biomarkers derived from lipids, nucleic acids, and proteins were analyzed in the EBC. Aerosol exposures were monitored during three major nanoparticle generation operations: smelting and welding (workshop 1) and nanocomposite machining (workshop 2) using a suite of real-time and integrated instruments. Mass concentrations during these operations were 0.120, 1.840, and 0.804 mg/m³, respectively. Median particle number concentrations were 4.8 × 10⁴, 1.3 × 10⁵, and 5.4 × 10⁵ particles/cm³, respectively. Nanoparticles accounted for 95, 40, and 61%, respectively, with prevailing Fe and Mn. All markers of nucleic acid and protein oxidation, malondialdehyde, and aldehydes C₆⁻C13 were elevated, already in the pre-shift samples relative to controls in both workshops. Significant post-shift elevations were documented in lipid oxidation markers. Significant associations were found between working in nanocomposite synthesis and EBC biomarkers. More research is needed to understand the contribution of nanoparticles from nanocomposite processing in inducing oxidative stress, relative to other co-exposures generated during welding, smelting, and secondary oxidation processes, in these workshops.

The many ways sputum flows - Dealing with high within-subject variability in cystic fibrosis sputum rheology

We evaluated test-retest reliability of sputum viscoelastic properties in clinically stable patients with cystic fibrosis (CF). Data from a prospective, randomized crossover study was used to determine within-subject variability of sputum viscoelasticity (G', storage modulus and G", loss modulus at 1 and 10 rad s^-1) and solids content over three consecutive visits. Precision of sputum properties was quantified by within-subject standard deviation (SD_ws), coefficient of variation (CV) and intraclass correlation coefficients (ICC). Fifteen clinically stable adults with CF (FEV₁ range 24-94% predicted) were included. No differences between study visits (mean ± SD 8 ± 2 days) were observed for any sputum rheology measure. CV's for G', G" and solids content ranged between 40.3-45.3% and ICC's between 0.21-0.42 indicating poor to fair test-retest reliability. Short-term within-subject variability of sputum properties is high in clinically stable adults with CF. Investigators applying shear rheology experiments in future prospective studies should consider using multiple measurements aiming to increase precision of sputum rheological outcomes.

Evolution of Stenotrophomonas maltophilia in Cystic Fibrosis Lung over Chronic Infection: A Genomic and Phenotypic Population Study

Stenotrophomonas maltophilia has been recognized as an emerging multi-drug resistant opportunistic pathogen in cystic fibrosis (CF) patients. We report a comparative genomic and phenotypic analysis of 91 S. maltophilia strains from 10 CF patients over a 12-year period. Draft genome analyses included in silico Multi-Locus Sequence Typing (MLST), Single-Nucleotide Polymorphisms (SNPs), and pangenome characterization. Growth rate, biofilm formation, motility, mutation frequency, in vivo virulence, and in vitro antibiotic susceptibility were determined and compared with population structure over time. The population consisted of 20 different sequence types (STs), 11 of which are new ones. Pangenome and SNPs data showed that this population is composed of three major phylogenetic lineages. All patients were colonized by multiple STs, although most of them were found in a single patient and showed persistence over years. Only few phenotypes showed some correlation with population phylogenetic structure. Our results show that S. maltophilia adaptation to CF lung is associated with consistent genotypic and phenotypic heterogeneity. Stenotrophomonas maltophilia infecting multiple hosts likely experiences different selection pressures depending on the host environment. The poor genotype-phenotype correlation suggests the existence of complex regulatory mechanisms that need to be explored in order to better design therapeutic strategies.

Measurement and Clinical Significance of Biomarkers of Oxidative Stress in Humans

Oxidative stress is the result of the imbalance between reactive oxygen species (ROS) formation and enzymatic and nonenzymatic antioxidants. Biomarkers of oxidative stress are relevant in the evaluation of the disease status and of the health-enhancing effects of antioxidants. We aim to discuss the major methodological bias of methods used for the evaluation of oxidative stress in humans. There is a lack of consensus concerning the validation, standardization, and reproducibility of methods for the measurement of the following: (1) ROS in leukocytes and platelets by flow cytometry, (2) markers based on ROS-induced modifications of lipids, DNA, and proteins, (3) enzymatic players of redox status, and (4) total antioxidant capacity of human body fluids. It has been suggested that the bias of each method could be overcome by using indexes of oxidative stress that include more than one marker. However, the choice of the markers considered in the global index should be dictated by the aim of the study and its design, as well as by the clinical relevance in the selected subjects. In conclusion, the clinical significance of biomarkers of oxidative stress in humans must come from a critical analysis of the markers that should give an overall index of redox status in particular conditions.

Water extract of Helminthostachys zeylanica attenuates LPS-induced acute lung injury in mice by modulating NF-κB and MAPK pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Previous studies showed that Helminthostachys zeylanica (L.) Hook. could reduce inflammatory responses in macrophage and brain astrocytes.

AIM OF THE STUDY

In the present study, we evaluated whether an ethyl acetate extract (HZE) or a water extract (HZW) of H. zeylanica could reduce inflammatory responses in lung epithelial cells and ameliorate lipopolysaccharide (LPS)-induced acute lung injury in mice.

METHODS

Human lung epithelial A549 cells were pre-treated with HZE or HZW (1-10μg/mL), then stimulated with LPS. BALB/c mice received oral HZW for 7 consecutive days, then an intratracheal instillation of LPS to induce lung injury.

RESULTS

HZW reduced chemokine and proinflammatory cytokine production in LPS-activated A549 cells. HZW also suppressed ICAM-1 expression and reduced the adherence of acute monocytic leukemia cells to inflammatory A549 cells. HZE had less efficacy than HZW in suppressing inflammatory responses in A549 cells. In vivo, HZW significantly suppressed neutrophil infiltration and reduced the TNF-α and IL-6 levels in bronchoalveolar lavage fluid and serum from LPS-treated mice. HZW also modulated superoxide dismutase activity, glutathione, and myeloperoxidase activity in lung tissues from LPS-treated mice. HZW decreased the phosphorylation of mitogen-activated protein kinase and nuclear factor kappa B, and promoted heme oxygenase-1 expression in inflamed lung tissue from LPS-treated mice.

CONCLUSION

Our findings suggested that HZW reduced lung injury in mice by reducing oxidative stress and inflammatory responses. HZW also reduced inflammatory responses in human lung epithelial cells.

Phloretin Attenuates Allergic Airway Inflammation and Oxidative Stress in Asthmatic Mice

Phloretin (PT), isolated from the apple tree, was previously demonstrated to have antioxidative and anti-inflammatory effects in macrophages and anti-adiposity effects in adipocytes. Inflammatory immune cells generate high levels of reactive oxygen species (ROS) for stimulated severe airway hyperresponsiveness (AHR) and airway inflammation. In this study, we investigated whether PT could reduce oxidative stress, airway inflammation, and eosinophil infiltration in asthmatic mice, and ameliorate oxidative and inflammatory responses in tracheal epithelial cells. BALB/c mice were sensitized with ovalbumin (OVA) to induce asthma symptoms. Mice were randomly assigned to the five experimental groups: normal controls; OVA-induced asthmatic mice; and OVA-induced mice injected intraperitoneally with one of the three PT doses (5, 10, or 20 mg/kg). In addition, we treated inflammatory human tracheal epithelial cells (BEAS-2B cells) with PT to assess oxidative responses and the levels of proinflammatory cytokines and chemokines. We found that PT significantly reduced goblet cell hyperplasia and eosinophil infiltration, which decreased AHR, inflammation, and oxidative responses in the lungs of OVA-sensitized mice. PT also decreased malondialdehyde levels in the lung and reduced Th2 cytokine production in bronchoalveolar lavage fluids. Furthermore, PT reduced ROS, proinflammatory cytokines, and eotaxin production in BEAS-2B cells. PT also suppressed monocyte cell adherence to inflammatory BEAS-2B cells. These findings suggested that PT alleviated pathological changes, inflammation, and oxidative stress by inhibiting Th2 cytokine production in asthmatic mice. PT showed therapeutic potential for ameliorating asthma symptoms in the future.

Lipoic acid and haloperidol-induced vacuous chewing movements: Implications for prophylactic antioxidant use in tardive dyskinesia

Tardive dyskinesia (TD), a potentially irreversible antipsychotic (AP)-related movement disorder, is a risk with all currently available antipsychotics. AP-induced vacuous chewing movements (VCMs) in rats, a preclinical model of TD, can be attenuated by antioxidant-based treatments although there is a shortage of well-designed studies. Lipoic acid (LA) represents a candidate antioxidant for the treatment of oxidative stress-related nervous system disorders; accordingly, its effects on AP-induced VCMs and striatal oxidative stress were examined. Rats treated with haloperidol decanoate (HAL; 21mg/kg every 3weeks, IM) for 12weeks were concurrently treated with LA (10 or 20mg/kg, PO). VCMs were assessed weekly by a blinded rater, and locomotor activity was evaluated as were striatal lipid peroxidation markers and serum HAL levels. VCMs were decreased by the lower dose (nonsignificant), whereas a significant increase was recorded with the higher dose of LA. HAL decreased locomotor activity and this was unaffected by LA. Striatal malondialdehyde (MDA) levels in HAL-treated rats were reduced by both LA doses, while 4-hydroxynonenal (4-HNE) levels were predictive of final VCM scores (averaged across weeks 10-12). Study limitations include differences between antipsychotics in terms of oxidative stress, LA dosing, choice of biomarkers for lipid peroxidation, and generalizability to TD in humans. Collectively, current preclinical evidence does not support a "protective" role for antioxidants in preventing TD or its progression, although clinical evidence offers limited evidence supporting such an approach.

Oxidative Stress and Bronchial Asthma in Children-Causes or Consequences?

Bronchial asthma is one of the most common chronic inflammatory diseases of the airways. In the pathogenesis of this disease, the interplay among the genes, intrinsic, and extrinsic factors are crucial. Various combinations of the involved factors determine and modify the final clinical phenotype/endotype of asthma. Oxidative stress results from an imbalance between the production of reactive oxygen species and reactive nitrogen species and the capacity of antioxidant defense mechanisms. It was shown that oxidative damage of biomolecules is strongly involved in the asthmatic inflammation. It is evident that asthma is accompanied by oxidative stress in the airways and in the systemic circulation. The oxidative stress is more pronounced during the acute exacerbation or allergen challenge. On the other hand, the genetic variations in the genes for anti-oxidative and pro-oxidative enzymes are variably associated with various asthmatic subtypes. Whether oxidative stress is the consequence of, or the cause for, chronic changes in asthmatic airways is still being discussed. Contribution of oxidative stress to asthma pathology remains at least partially controversial, since antioxidant interventions have proven rather unsuccessful. According to current knowledge, the relationship between oxidative stress and asthmatic inflammation is bidirectional, and genetic predisposition could modify the balance between these two positions-oxidative stress as a cause for or consequence of asthmatic inflammation.

Evidence of microvascular dysfunction in patients with cystic fibrosis

Cystic fibrosis (CF) is a genetic, multisystemic disorder with broad clinical manifestations apart from the well-characterized pulmonary dysfunction. Recent findings have described impairment in conduit vessel function in patients with CF; however, whether microvascular function is affected in this population has yet to be elucidated. Using laser-Doppler imaging, we evaluated microvascular function through postocclusive reactive hyperemia (PORH), local thermal hyperemia (LTH), and iontophoresis with acetylcholine (ACh). PORH [518 ± 174% (CF) and 801 ± 125% (control), P = 0.039], LTH [1,338 ± 436% (CF) and 1,574 ± 620% (control), P = 0.045], and iontophoresis with ACh [416 ± 140% (CF) and 617 ± 143% (control), P = 0.032] were significantly lower in patients with CF than control subjects. In addition, the ratio of PORH to LTH was significantly (P = 0.043) lower in patients with CF (55.3 ± 5.1%) than control subjects (68.8 ± 3.1%). Significant positive correlations between LTH and forced expiratory volume in 1 s (%predicted) (r = 0.441, P = 0.013) and between the PORH-to-LTH ratio and exercise capacity (r = 0.350, P = 0.049) were observed. These data provide evidence of microvascular dysfunction in patients with CF compared with control subjects. In addition, our data demonstrate a complex relationship between microvascular function and classical markers of disease severity (i.e., pulmonary function and exercise capacity) in CF.