Myeloperoxidase as an Active Disease Biomarker: Recent Biochemical and Pathological Perspectives

Chitosan and Lecithin Ameliorate Osteoarthritis Symptoms Induced by Monoiodoacetate in a Rat Model

The present work aimed to assess the chondroprotective influence of chitosan and lecithin in a monoiodoacetate (MIA)-induced experimental osteoarthritis (OA) model. Forty male rats weighing 180–200 g were randomly distributed among the following five experimental groups (eight per group): control, MIA-induced OA, MIA-induced OA + chitosan, MIA-induced OA + lecithin, and MIA-induced OA + chitosan + lecithin. The levels of TNF-α, IL6, RF, ROS, and CRP, as well as mitochondrial markers such as mitochondrial swelling, cytochrome C oxidase (complex IV), MMP, and serum oxidative/antioxidant status (MDA level) (MPO and XO activities) were elevated in MIA-induced OA. Also, SDH (complex II) activity in addition to the levels of ATP, glutathione (GSH), and thiol was markedly diminished in the MIA-induced OA group compared to in control rats. These findings show that mitochondrial function is associated with OA pathophysiology and suggest that chitosan and lecithin could be promising potential ameliorative agents in OA animal models. Lecithin was more effective than chitosan in ameliorating all of the abovementioned parameters.

Comparative proteomic analysis of dental cementum from deciduous and permanent teeth

BACKGROUND AND OBJECTIVES

Dental cementum (DC) is a mineralized tissue covering tooth roots that plays a critical role in dental attachment. Differences in deciduous vs. permanent tooth DC have not been explored. We hypothesized that proteomic analysis of DC matrix would identify compositional differences in deciduous (DecDC) vs. permanent (PermDC) cementum that might reflect physiological or pathological differences, such as root resorption that is physiological in deciduous teeth but can be pathological in the permanent dentition.

METHODS

Protein extracts from deciduous (n = 25) and permanent (n = 12) teeth were pooled (five pools of DecDC, five teeth each; four pools of PermDC, three teeth each). Samples were denatured, and proteins were extracted, reduced, alkylated, digested, and analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). The beta-binomial statistical test was applied to normalized spectrum counts with 5% significance level to determine differentially expressed proteins. Immunohistochemistry was used to validate selected proteins.

RESULTS

A total of 510 proteins were identified: 123 (24.1%) exclusive to DecDC; 128 (25.1%) exclusive to PermDC; 259 (50.8%) commonly expressed in both DecDC and PermDC. Out of 60 differentially expressed proteins, 17 (28.3%) were detected in DecDC, including myeloperoxidase (MPO), whereas 43 (71.7%) were detected in PermDC, including decorin (DCN) and osteocalcin (BGLAP). Overall, Gene Ontology (GO) analysis indicated that all expressed proteins were related to GO biological processes that included localization and response to stress, and the GO molecular function of differentially expressed proteins was enriched in cell adhesion, molecular binding, cytoskeletal protein binding, structural molecular activity, and macromolecular complex binding. Immunohistochemistry confirmed the trends for selected differentially expressed proteins in human teeth.

CONCLUSIONS

Clear differences were found between the proteomes of DecDC and PermDC. These findings may lead to new insights into developmental differences between DecDC and PermDC, as well as to a better understanding of physiological/pathological events such as root resorption.

Visfatin Exerts Immunotherapeutic Effects in Lipopolysaccharide-Induced Acute Lung Injury in Murine Model

Visfatin acts as a significant regulator of inflammatory cytokines. However, the immunological response and therapeutic effects of visfatin under bacterial stress in murine lung tissue are still not clear. To investigate the role of visfatin on lipopolysaccharide (LPS)-induced acute lung injury (ALI), thirty Kunming mice were divided into Saline, LPS, and LPS + visfatin groups. After routine blood examination, the effects of visfatin on inflammatory cytokines, lung tissue structure, and expression of inflammatory mediators were explored through hematoxylin-eosin (H&E), Masson and immunohistochemical staining, quantitative polymerase chain reaction (Q-PCR), and Western blotting. Compared with the Saline group, neutrophil percentage, peripheral blood neutrophil count, and the ratio of lymphocyte count (NLR) were upregulated in LPS group. Moreover, Masson staining showed alterations in lung tissue structure; the mRNA level of different cytokines (IL-6, IL-1β, TNF-α, IL-10, TLR4, IFN-γ) was upregulated; and the protein expression of interleukin (IL)-6, myeloperoxidase (MPO), and transforming growth factor-β1 (TGF-β) was significantly (p < 0.05) different in LPS group. Compared with LPS group, neutrophil percentage significantly decreased (p < 0.01), the numbers of lymphocytes significantly (p < 0.05) increased, NLR decreased, Masson staining of the lung was extremely different (p < 0.01), the structure of the lung was slightly damaged, and the myeloperoxidase values of lung showed no differences in LPS + visfatin. Hence, visfatin inhibits the lung inflammation induced by ALI. During the ALI, visfatin acts by decreasing NLR, downregulated the expression of MPO, enhanced antioxidant capacity, and regulated the inflammatory factors IL-1β, IL-6, IL-10, and TNF-α to reduce the lung injury.

Associations of myeloperoxidase, interleukin-17A and heparin-binding EGF-like growth factor levels with in-stent restenosis after percutaneous coronary intervention: a single-centre case-control study in China

OBJECTIVES

To investigate the changes in serum myeloperoxidase (MPO), interleukin (IL)-17A and heparin-binding EGF-like growth factor (HB-EGF) levels before and after percutaneous coronary intervention (PCI), and to evaluate the associations of MPO, IL-17A and HB-EGF levels with the 1-year restenosis rate.

DESIGN

Case-control study.

SETTINGS

Xiangyang Central Hospital between January 2012 and December 2017.

PARTICIPANTS

Patients with coronary heart disease who underwent PCI.

INTERVENTIONS

Not applicable.

PRIMARY AND SECONDARY OUTCOME MEASURES

Not applicable.

RESULTS

Finally, 407 and 132 patients were included in the control and in-stent restenosis (ISR) groups, respectively. The general clinical characteristics of the patients were not significantly different between the two groups. The MPO, IL-17A and HB-EGF levels were not significantly different between the two groups at baseline but significantly increased after PCI. The ISR group showed higher levels of MPO, IL-17A and HB-EGF compared with the control group at all postoperative time points. Multivariable analysis showed that MPO, IL-17A and HB-EGF were associated with increased ISR [MPO (OR=1.003; 95% CI: 1.001 to 1.005; p=0.002), IL-17A (OR=1.015; 95% CI: 1.009 to 1.020; p<0.0001) and HB-EGF (OR=2.256; 95% CI: 1.103 to 4.009; p=0.002)]. All three factors had sensitivity and specificity ≥68% for ISR.

CONCLUSIONS

HB-EGF could be used for the detection of ISR after PCI and could be of use for the prediction of ISR, but the value of MPO and IL-17A might be more limited. This will have to be validated in future studies.

Neutrophil-to-Lymphocyte Ratio: A Biomarker to Monitor the Immune Status of Astronauts

A comprehensive understanding of spaceflight factors involved in immune dysfunction and the evaluation of biomarkers to assess in-flight astronaut health are essential goals for NASA. An elevated neutrophil-to-lymphocyte ratio (NLR) is a potential biomarker candidate, as leukocyte differentials are altered during spaceflight. In the reduced gravity environment of space, rodents and astronauts displayed elevated NLR and granulocyte-to-lymphocyte ratios (GLR), respectively. To simulate microgravity using two well-established ground-based models, we cultured human whole blood-leukocytes in high-aspect rotating wall vessels (HARV-RWV) and used hindlimb unloaded (HU) mice. Both HARV-RWV simulation of leukocytes and HU-exposed mice showed elevated NLR profiles comparable to spaceflight exposed samples. To assess mechanisms involved, we found the simulated microgravity HARV-RWV model resulted in an imbalance of redox processes and activation of myeloperoxidase-producing inflammatory neutrophils, while antioxidant treatment reversed these effects. In the simulated microgravity HU model, mitochondrial catalase-transgenic mice that have reduced oxidative stress responses showed reduced neutrophil counts, NLR, and a dampened release of selective inflammatory cytokines compared to wildtype HU mice, suggesting simulated microgravity induced oxidative stress responses that triggered inflammation. In brief, both spaceflight and simulated microgravity models caused elevated NLR, indicating this as a potential biomarker for future in-flight immune health monitoring.

The Dual Role of Myeloperoxidase in Immune Response

The heme protein myeloperoxidase (MPO) is a major constituent of neutrophils. As a key mediator of the innate immune system, neutrophils are rapidly recruited to inflammatory sites, where they recognize, phagocytose, and inactivate foreign microorganisms. In the newly formed phagosomes, MPO is involved in the creation and maintenance of an alkaline milieu, which is optimal in combatting microbes. Myeloperoxidase is also a key component in neutrophil extracellular traps. These helpful properties are contrasted by the release of MPO and other neutrophil constituents from necrotic cells or as a result of frustrated phagocytosis. Although MPO is inactivated by the plasma protein ceruloplasmin, it can interact with negatively charged components of serum and the extracellular matrix. In cardiovascular diseases and many other disease scenarios, active MPO and MPO-modified targets are present in atherosclerotic lesions and other disease-specific locations. This implies an involvement of neutrophils, MPO, and other neutrophil products in pathogenesis mechanisms. This review critically reflects on the beneficial and harmful functions of MPO against the background of immune response.

The Role of Inflammation and Myeloperoxidase-Related Oxidative Stress in the Pathogenesis of Genetically Triggered Thoracic Aortic Aneurysms

Genetically triggered thoracic aortic aneurysms (TAAs) are usually considered to exhibit minimal levels of inflammation. However, emerging data demonstrate that specific features of an inflammatory response can be observed in TAA, and that the extent of the inflammatory response can be correlated with the severity, in both mouse models and in human studies. Myeloperoxidase (MPO) is a key mediator of the inflammatory response, via production of specific oxidative species, e.g., the hypohalous acids. Specific tissue modifications, mediated by hypohalous acids, have been documented in multiple cardiovascular pathologies, including atherosclerosis associated with coronary artery disease, abdominal aortic, and cerebral aneurysms. Similarly, data are now emerging that show the capacity of MPO-derived oxidative species to regulate mechanisms important in TAA pathogenesis, including alterations in extracellular matrix homeostasis, activation of matrix metalloproteinases, induction of endothelial dysfunction and vascular smooth muscle cell phenotypic switching, and activation of ERK1/2 signaling. The weight of evidence supports a role for inflammation in exacerbating the severity of TAA progression, expanding our understanding of the pathogenesis of TAA, identifying potential biomarkers for early detection of TAA, monitoring severity and progression, and for defining potential novel therapeutic targets.

The Challenge by Multiple Environmental and Biological Factors Induce Inflammation in Aging: Their Role in the Promotion of Chronic Disease

The aging process is driven by multiple mechanisms that lead to changes in energy production, oxidative stress, homeostatic dysregulation and eventually to loss of functionality and increased disease susceptibility. Most aged individuals develop chronic low-grade inflammation, which is an important risk factor for morbidity, physical and cognitive impairment, frailty, and death. At any age, chronic inflammatory diseases are major causes of morbimortality, affecting up to 5-8% of the population of industrialized countries. Several environmental factors can play an important role for modifying the inflammatory state. Genetics accounts for only a small fraction of chronic-inflammatory diseases, whereas environmental factors appear to participate, either with a causative or a promotional role in 50% to 75% of patients. Several of those changes depend on epigenetic changes that will further modify the individual response to additional stimuli. The interaction between inflammation and the environment offers important insights on aging and health. These conditions, often depending on the individual's sex, appear to lead to decreased longevity and physical and cognitive decline. In addition to biological factors, the environment is also involved in the generation of psychological and social context leading to stress. Poor psychological environments and other sources of stress also result in increased inflammation. However, the mechanisms underlying the role of environmental and psychosocial factors and nutrition on the regulation of inflammation, and how the response elicited for those factors interact among them, are poorly understood. Whereas certain deleterious environmental factors result in the generation of oxidative stress driven by an increased production of reactive oxygen and nitrogen species, endoplasmic reticulum stress, and inflammation, other factors, including nutrition (polyunsaturated fatty acids) and behavioral factors (exercise) confer protection against inflammation, oxidative and endoplasmic reticulum stress, and thus ameliorate their deleterious effect. Here, we discuss processes and mechanisms of inflammation associated with environmental factors and behavior, their links to sex and gender, and their overall impact on aging.

Monitoring the Redox Status in Multiple Sclerosis

Worldwide, over 2.2 million people suffer from multiple sclerosis (MS), a multifactorial demyelinating disease of the central nervous system. MS is characterized by a wide range of motor, autonomic, and psychobehavioral symptoms, including depression, anxiety, and dementia. The blood, cerebrospinal fluid, and postmortem brain samples of MS patients provide evidence on the disturbance of reduction-oxidation (redox) homeostasis, such as the alterations of oxidative and antioxidative enzyme activities and the presence of degradation products. This review article discusses the components of redox homeostasis, including reactive chemical species, oxidative enzymes, antioxidative enzymes, and degradation products. The reactive chemical species cover frequently discussed reactive oxygen/nitrogen species, infrequently featured reactive chemicals such as sulfur, carbonyl, halogen, selenium, and nucleophilic species that potentially act as reductive, as well as pro-oxidative stressors. The antioxidative enzyme systems cover the nuclear factor erythroid-2-related factor 2 (NRF2)-Kelch-like ECH-associated protein 1 (KEAP1) signaling pathway. The NRF2 and other transcriptional factors potentially become a biomarker sensitive to the initial phase of oxidative stress. Altered components of the redox homeostasis in MS were discussed in search of a diagnostic, prognostic, predictive, and/or therapeutic biomarker. Finally, monitoring the battery of reactive chemical species, oxidative enzymes, antioxidative enzymes, and degradation products helps to evaluate the redox status of MS patients to expedite the building of personalized treatment plans for the sake of a better quality of life.

Association of Genes Related to Oxidative Stress with the Extent of Coronary Atherosclerosis

Oxidative stress is believed to play a critical role in atherosclerosis initiation and progression. In line with this, in a group of 1099 subjects, we determined eight single nucleotide polymorphisms (SNPs) related to oxidative stress (PON1 c.575A>G, MPO c.−463G>A, SOD2 c.47T>C, GCLM c.−590C>T, NOS3 c.894G>T, NOS3 c.−786T>C, CYBA c.214C>T, and CYBA c.−932A>G) and assessed the extent of atherosclerosis in coronary arteries based on Gensini score. An increased risk of having a Gensini score in the higher half of the distribution was observed for the PON1 c.575G allele (odds ratio (OR) = 1.27, 95% confidence interval (CI): 1.004–1.617, p = 0.046). Next, the genetic risk score (GRS) for the additive effect of the total number of pro-oxidative alleles was assessed. We noted an increase in the risk of having a Gensini score above the median with the maximum number of risk alleles (OR = 2.47, 95% CI: 1.19–5.23, p = 0.014). A univariate Spearman’s test revealed significant correlation between the total number of pro-oxidant alleles (GRS) and the Gensini score (ρ = 0.068, p = 0.03). In conclusion, the PON1 c.575A>G variant and the high number of risk alleles (GRS) were independent risk factors for a high Gensini score. We suggest, however, that GRS might occur as a more valuable component in adding a predictive value to the genetic background of atherosclerosis.

The Inclusion of the Microalga Scenedesmus sp. in Diets for Rainbow Trout, Onchorhynchus mykiss, Juveniles

Simple Summary

This study aimed to evaluate the suitability of the microalga Scenedesmus sp. in diets for rainbow trout juveniles. Considering previous results with similar species, the authors tested the inclusion of this microalga at 5% in diets (48% protein and 18% lipid levels). After 45 days, neither trout growth nor feed efficiency parameters nor fillet proximate composition were negatively affected by the inclusion of the microalga in the diet. In addition, provision of the diet containing the microalga did not lead to observable negative effects on liver or intestinal histological organization and function. Dietary Scenedesmus sp. improved the nutritional quality of the fillet in terms of n-3 polyunsaturated fatty acid (PUFA) levels, especially docosahexanoic acid (DHA), although it did alter the color of the fillet. In addition, feeding rainbow trout with diets containing Scenedesmus sp. modified the lipid class composition in the liver by increasing the levels of polar phospholipids with regard to triacylglycerides; results that may be attributed to dietary-induced changes in lipid metabolism. Results showed that the green microalga Scenedesmus sp. is a safe ingredient for compound feeds in rainbow trout when considering fish growth performance, condition, and health parameters, although the visual appearance of the fillet was affected.

Abstract

A nutritional study was conducted to evaluate the inclusion of the green microalga Scenedesmus sp. at 5% (SCE-5) as an alternative fishmeal ingredient. This microalga was tested with four replicates during 45 days using isolipidic (18%), isoproteic (48%), and isoenergetic (1.9 MJ kg⁻¹) diets. Fish fed Scenedesmus sp. showed similar growth and feed efficiency parameters as the control group. Regarding the digestive function, the SCE-5 diet enhanced the activity of alkaline pancreatic proteases, whereas it did not affect that of intestinal enzymes involved in nutrient absorption. No histological alterations were found in fish fed the SCE-5 diet, although a higher density of goblet cells in the anterior intestine and changes in gut microbiome diversity were found in this group, which collectively suggests positive effects of this green microalga on the intestine. Dietary Scenedesmus sp. improved the fillet’s nutritional quality in terms of n-3 polyunsaturated fatty acid (PUFA) levels, although it also increased its yellowish color. The overall results of this study showed that Scenedesmus sp. is a safe ingredient for compound feeds in rainbow trout when considering fish growth performance, animal condition, and health parameters, although it substantially affected the color of the fillet that may potentially affect consumers’ preferences.

Joint Measurements of Leukocyte Elastase and Myeloperoxidase Promote Identification of the State of Neutrophils in Diabetic Patients

The clinic of diabetes mellitus (DM) offers a number of hypotheses about the leading role of polymorphonuclear neutrophils (PMNs) in both oxidative stress and diabetic complications. However, the results of numerous studies are extremely controversial. Why is it so? We appreciated the clinical significance of simultaneous measurement data of several PMN parameters, which must complement each other. For this purpose, myeloperoxidase (MPO) and elastase (EL) were jointly analyzed in the blood plasma from 160 type 2 diabetes mellitus patients with high levels of HbA_1c. A weakly positive correlation (r ∼ 0.56) was observed between MPO and EL analytical data, and any correlation between the concentrations of MPO/EL and HbA_1c was absent. Medians of 160 measurements of MPO/EL concentrations were ∼103/190 ng/mL, and 95% of all results were in the range below 320/1016 ng/mL, respectively. The share of DM patients whose concentrations of MPO, EL, or either of two parameters exceeded the corresponding reference values was 65%, 80%, and 82.5%, respectively. These findings—a high intensity of neutrophil degranulation process—indicated that some diabetic conditions promote the transfer of PMNs to an “arousal” or “subactivation” state, which is identical or similar to their activation, providing in vivo an almost inexhaustible source of extremely “aggressive” MPO and EL. Thus, the conjoint MPO/EL measurements confirm the leading role of PMNs in the development of various complications of diabetes. The paradox is that the diagnostic significance of MPO/EL as independent parameters in diabetic patients is unambiguous for a number of reasons.

Myeloperoxidase and Lysozymes as a Pivotal Hallmark of Immunity Status in Rabbits

Simple Summary

Rabbit breeding is a very important element in the context of broadly understood industrial breeding, as rabbits are one of the main and most frequently chosen economic directions. Effective rabbit breeding, however, requires full control over the health of these animals, which is particularly related to the orientation regarding their immune status. There are many indicators that can be used to assess the immune system, but the greatest attention should be paid to those that change rapidly over time and reflect the body’s first line of defense. Peripheral blood granulocytes contain enzymes with strong antimicrobial properties, the level of which changes as a result of various external factors, e.g., viral infection, which was assessed in this study. The aim of the study was to evaluate the dynamics of myeloperoxidase (MPO) and lysozyme (LZM) in the experimental infection of rabbits with the Lagovirus europaeus/GI.1a virus, which is a pathogen causing high mortality, decimating rabbit farms all over the world in a short time. The results obtained in the dynamic system show that the levels of assessed enzymes significantly change in the blood during infection. Assessing the immune system using these indicators could therefore be a potential biomarker for the immune status of rabbits.

Abstract

Infectious diseases, due to their massive scale, are the greatest pain for all rabbit breeders. Viral infections cause enormous economic losses in farms. Treating sick rabbits is very difficult and expensive, so it is very important to prevent disease by vaccinating. In order to successfully fight viral infections, it is important to know about the immune response of an infected animal. The aim of this study was to analyze the immune response mediated by antimicrobial peptides (myeloperoxidase (MPO) and lysozyme (LZM)) in peripheral blood neutrophils and rabbit serum by non-invasive immunological methods. The study was carried out on mixed breed rabbits that were experimentally infected with two strains (Erfurt and Rossi) of the Lagovirus europaeus/GI.1a virus. It has been observed that virus infection causes changes in the form of statistically significant increases in the activity of MPO and LZM concentration, while in the case of LZM activity only statistically significant decreases were noted. Additionally, clinical symptoms typical for the course of the disease were noted, and the probability of survival of the animals at 60 h p.i. (post infection) was 30% for the Erfurt strain, and −60% for the Rossi strain. The obtained results of MPO and LZMs suggest that these enzymes, especially MPO, may serve as a prognostic marker of the state of the immune system of rabbits.

Biomarkers of inflammation, hypercoagulability and endothelial injury predict early asymptomatic doxorubicin-induced cardiotoxicity in breast cancer patients

Doxorubicin (DOX)-induced cardiotoxicity is a major limitation to its clinical application. Cardiotoxicity of DOX is dose-dependent that begins with the first dose. Oxidative stress and inflammation are involved in DOX-related cardiotoxicity. This study aimed to determine whether multiple markers of inflammation, hypercoagulability and endothelial injury correlate with the risk of early DOX-induced cardiotoxicity in breast cancer patients. Blood samples of 51 breast cancer patients treated with DOX-based chemotherapy were collected before (baseline) and after the first cycle of chemotherapy. The risk of cardiotoxicity was defined as an asymptomatic reduction of cardiac left ventricle ejection fraction (LVEF) >10% at completion of chemotherapy versus baseline. Plasma samples were examined for multiple biomarkers of inflammation, hypercoagulability and endothelial dysfunction, including C-reactive protein (CRP), thrombomodulin (TM), thrombin-antithrombin complex (TAT), myeloperoxidase (MPO), von Willebrand factor (vWF) and P-selectin. Surrogate markers of neutrophil extracellular traps (NETs) nucleosomes and double stranded DNA (dsDNA) were also measured. Patients with abnormal decline of LVEF >10% (n=21) had significantly elevated levels of MPO and TM both at baseline, and after the first dose of DOX-based chemotherapy relative to patients with normal LVEF (n=30) after adjusting for race, age, BMI and type of breast cancer. The first dose of DOX also induced significantly higher circulating levels of TAT complex and nucleosomes in patients at risk of cardiotoxicity in comparison with patients without. The comparison between the means of the biomarkers in after-before DOX-based chemotherapy of the two groups of patients showed significant differences for MPO, TAT complex and CRP. The results from this study suggest that the risk of DOX-induced cardiotoxicity in breast cancer is associated with endothelial dysfunction, inflammation and prothrombotic state before and after the first dose of chemotherapy.

Inhibition of miRNA-34a Promotes M2 Macrophage Polarization and Improves LPS-Induced Lung Injury by Targeting Klf4

Acute respiratory distress syndrome (ARDS) is an outcome of an accelerated immune response that starts initially as a defensive measure, however, due to non-canonical signaling, it later proves to be fatal not only to the affected tissue but to the whole organ system. microRNAs are known for playing a decisive role in regulating the expression of genes involved in diverse functions such as lung development, repair, and inflammation. In-silico analyses of clinical data and microRNA databases predicted a probable interaction between miRNA-34a (miR-34a), mitogen-activated protein kinase 1 (ERK), and kruppel like factor 4 (Klf4). Parallel to in silico results, here, we show that intra-tracheal instillation of lipopolysaccharides (LPS) to mice enhanced miR-34a expression in lung macrophages. Inhibition of miR-34a significantly improved lung histology, whereas over-expression of miR-34a worsened the lung injury phenotype. miR-34a over-expression in macrophages were also demonstrated to favour pro-inflammatory M1 phenotype and inhibition of M2 polarization. In a quest to confirm this likely interaction, expression profiles of Klf4 as the putative target were analyzed in different macrophage polarizing conditions. Klf4 expression was found to be prominent in the miR-34a inhibitor-treated group but down-regulated in the miR-34a mimic treated group. Immuno-histopathological analyses of lung tissue from the mice treated with miR-34a inhibitor also showed reduced inflammatory M1 markers as well as enhanced cell proliferation. The present study indicates that miR-34a intensified LPS-induced lung injury and inflammation by regulating Klf4 and macrophage polarization, which may serve as a potential therapeutic target for acute lung injury/ARDS.

Inflammatory state of lymphatic vessels and miRNA profiles associated with relapse in ovarian cancer patients

Lymphogenic spread is associated with poor prognosis in epithelial ovarian cancer (EOC), yet little is known regarding roles of non-peri-tumoural lymphatic vessels (LVs) outside the tumour microenvironment that may impact relapse. The aim of this feasibility study was to assess whether inflammatory status of the LVs and/or changes in the miRNA profile of the LVs have potential prognostic and predictive value for overall outcome and risk of relapse. Samples of macroscopically normal human lymph LVs (n = 10) were isolated from the external iliac vessels draining the pelvic region of patients undergoing debulking surgery. This was followed by quantification of the inflammatory state (low, medium and high) and presence of cancer-infiltration of each LV using immunohistochemistry. LV miRNA expression profiling was also performed, and analysed in the context of high versus low inflammation, and cancer-infiltrated versus non-cancer-infiltrated. Results were correlated with clinical outcome data including relapse with an average follow-up time of 13.3 months. The presence of a high degree of inflammation correlated significantly with patient relapse (p = 0.033). Cancer-infiltrated LVs showed a moderate but non-significant association with relapse (p = 0.07). Differential miRNA profiles were identified in cancer-infiltrated LVs and those with high versus low inflammation. In particular, several members of the let-7 family were consistently down-regulated in highly inflamed LVs (>1.8-fold, p<0.05) compared to the less inflamed ones. Down-regulation of the let-7 family appears to be associated with inflammation, but whether inflammation contributes to or is an effect of cancer-infiltration requires further investigation.

Sensitive and rapid lateral-flow assay for early detection of subclinical mammary infection in dairy cows

Detection of subclinical mastitis (SCM) in its initial stage can save great economic losses, improve milk quality and animal welfare. We have developed a semiquantitative lateral flow assay for the detection of SCM in dairy cows targeting myeloperoxidase (MPO) enzyme of milk neutrophils. A competitive immunoassay format was used, and colloidal gold nanoparticles (GNP) were prepared and used as a labelling agent. Monoclonal anti-MPO antibodies were used and assessed for its quality by enzyme-linked immunosorbent assay and dot blot. Conjugation method for GNP and anti-MPO antibodies was standardised, and the conjugate was placed over the conjugate pad. MPO coupled with a carrier protein (OVA) and the species-specific secondary antibodies were placed on test and control lines, respectively. The developed assay was verified with 75 milk samples collected from healthy, SCM and clinical mastitis cows. It displayed a high sensitivity as it could detect MPO as low as 1.5 ng/ml, an accuracy greater than 97% and showed no crossreactivity when crosschecked with other milk proteins. The developed assay can be used as an alternative for SCM diagnostic tests where lab structure are available for obtaining the lysate of milk SCC.

Radiation activates myeloperoxidase (MPO) to generate active chlorine species (ACS) via a dephosphorylation mechanism - inhibitory effect of LGM2605

BACKGROUND

Radiation exposure of tissues is associated with inflammatory cell influx. Myeloperoxidase (MPO) is an enzyme expressed in granulocytes, such as neutrophils (PMN) and macrophages, responsible for active chlorine species (ACS) generation. The present study aimed to: 1) determine whether exposure to γ-irradiation induces MPO-dependent ACS generation in murine PMN; 2) elucidate the mechanism of radiation-induced ACS generation; and 3) evaluate the effect of the synthetic lignan LGM2605, known for ACS scavenging properties.

METHODS

MPO-dependent ACS generation was determined by using hypochlorite-specific 3'-(p-aminophenyl) fluorescein (APF) and a highly potent MPO inhibitor, 4-aminobenzoic acid hydrazide (ABAH), and confirmed in PMN derived from MPO-/- mice. Radiation-induced MPO activation was determined by EPR spectroscopy and computational analysis identified tyrosine, serine, and threonine residues near MPO's active site.

RESULTS

γ-radiation increased MPO-dependent ACS generation dose-dependently in human MPO and in wild-type murine PMN, but not in PMN from MPO-/- mice. LGM2605 decreased radiation-induced, MPO-dependent ACS. Protein tyrosine phosphatase (PTP) and protein serine/threonine phosphatase (PSTP) inhibitors decreased the radiation-induced increase in ACS. Peroxidase cycle results demonstrate that tyrosine phosphorylation blocks MPO Compound I formation by preventing catalysis on H2O2 in the active site of MPO. EPR data demonstrate that γ-radiation increased tyrosyl radical species formation in a dose-dependent manner.

CONCLUSIONS

We demonstrate that γ-radiation induces MPO-dependent generation of ACS, which is dependent, at least in part, by protein tyrosine and Ser/Thr dephosphorylation and is reduced by LGM2605. This study identified for the first time a novel protein dephosphorylation-dependent mechanism of radiation-induced MPO activation.

Myeloperoxidase: a potential therapeutic target for coronary artery disease

INTRODUCTION

Coronary artery disease (CAD) poses significant morbidity and mortality globally. Despite significant advances in treatment interventions, residual cardiovascular risks remain unchecked. Recent clinical trials have shed light on the potential therapeutic benefits of targeting anti-inflammatory pathways. Myeloperoxidase (MPO) plays an important role in atherosclerotic plaque formation and destabilization of the fibrous cap; both increase the risk of atherosclerotic cardiovascular disease and especially CAD.

AREAS COVERED

This article examines the role of MPO in the pathogenesis of atherosclerotic CAD and the mechanistic data from several key therapeutic drug targets. There have been numerous interesting studies on prototype compounds that directly or indirectly attenuate the enzymatic activities of MPO, and subsequently exhibit atheroprotective effects; these include aminobenzoic acid hydrazide, ferulic acid derivative (INV-315), thiouracil derivatives (PF-1355 and PF-06282999), 2-thioxanthines derivative (AZM198), triazolopyrimidines, acetaminophen, N-acetyl lysyltyrosylcysteine (KYC), flavonoids, and alternative substrates such as thiocyanate and nitroxide radical.

EXPERT OPINION

Future investigations must determine if the cardiovascular benefits of direct systemic inhibition of MPO outweigh the risk of immune dysfunction, which may be less likely to arise with alternative substrates or MPO inhibitors that selectively attenuate atherogenic effects of MPO.

Antihemorrhoidal activity of organic acids of Capsella bursa-pastoris on croton oil-induced hemorrhoid in rats

This study was aimed to investigate the antihemorrhoidal effects of ethanol (CBE) and water extracts (CBW) of Capsella bursa-pastoris, an edible plant and a precipitant (CBW-1) obtained from the CBW in croton oil (CO)-induced hemorrhoid model in rats. CBW-1 was contain three organic acids, citric acid (36.09%), malic acid (35.56%), and quinic acid (17.73%). Hemorrhoids were evaluated by histopathology of recto-anal tissues and biochemical parameters in plasma and recto-anal tissues of rats. CBW, CBE, and CBW-1 significantly reduced hemorrhagic necrotic enteritis induced by CO. CO also increased the cytokines and lipid peroxidation (LPO) in serum, and myeloperoxidase (MPO) activity and LPO in recto-anal tissues, and reduced the GSH, CAT, GPx, and SOD levels in serum and recto-anal tissues. However, CBE, CBW, and CBW-1 ameliorated the levels of the cytokines, LPO, MPO, and the antioxidants. Our results conclude that the curative effect of Capsella bursa-pastoris is closely related with its organic acids constituents, citric, malic, and quinic acids. PRACTICAL APPLICATIONS: The fresh leaves of Capsella bursa-pastoris are edible, eaten raw or cooked, and also used in salad. It has a widespread traditional usage in the treatment of the hemorrhoids in the Anatolia and in the Middle East Countries. According to our literature survey, any scientific evidence has not been found in the literature that C. bursa-pastoris could be used in the treatment of hemorrhoids. Therefore, in the current study, we aimed to investigate the antihemorrhoidal and antioxidant effects of ethanol and water extracts, and a precipitant (CBW-1) obtained from the CBW of C. bursa-pastoris in croton oil (CO)-induced hemorrhoid model in rats. The current results showed that its water extract and CBW-1 containing three organic acids, citric acid (36.09%), malic acid (35.56%), and quinic acid (17.73%) significantly reduced the hemorrhagic necrotic enteritis induced by CO ameliorating the levels of the cytokines, LPO, MPO, and the antioxidants. Our results conclude that the curative effect of C. bursa-pastoris is closely related with its organic acids constituents, citric, malic, and quinic acids.

Design, synthesis and pharmacological assessment of new pyrazole compounds

AIMS

This study investigated the antinociceptive and anti-inflammatory effects of new pyrazole compounds LQFM011(5), LQFM043(6) and LQFM044(7) as well as the mechanisms of action and acute in vitro toxicity.

MAIN METHODS

The antinociceptive activity was evaluated using the acetic acid-induced abdominal writhing test, formalin-induced pain test and the Randall-Selitto test. The anti-inflammatory activity was evaluated using models of paw oedema and pleurisy induced by carrageenan; cell migration, the levels of tumour necrosis factor α (TNF-α) and myeloperoxidase (MPO) enzyme activity were evaluated. In addition, the ability to inhibit phospholipase A2 (PLA2) in vitro and docking in PLA2 were used. Acute oral systemic toxicity in mice was evaluated through the neutral red uptake assay.

KEY FINDINGS

The synthesised compounds (5-7), delivered via gavage (p.o.) at 70, 140 or 280 µmol/kg, decreased the number of writhings induced by acetic acid; the three compounds (280 µmol/kg p.o.) reduced the paw licking time in the first and second phase of the formalin test and decreased the nociceptive threshold variation in the Randall-Selitto test. Furthermore, this dose reduced oedema formation, leucocyte migration (specifically through reduction in polymorphonuclear cell movement) and increased mononuclear cells. MPO activity and the levels of pro-inflammatory cytokines TNF-α were decreased. Evaluation of PLA2 inhibition via the docking simulation revealed more interactions of LQFM043R(6) and LQFM044(7), data that corroborated the half-maximal inhibitory concentration (IC₅₀) of PLA2 inhibition in vitro. Therefore, LQFM011(5), LQFM043(6) and LQFM044(7) were classified with the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) as category 4.

Caffeine prevents hyperoxia-induced lung injury in neonatal mice through NLRP3 inflammasome and NF-κB pathway

Background

Bronchopulmonary dysplasia (BPD) is a common chronic lung disease in premature infants and hyperoxia exposure is a major cause. In hyperoxic lung injury animal model, alveolar simplification and pro-inflammatory cells infiltration are the main pathophysiologic changes. Caffeine is a drug used to treat apnea in premature infants. Early use of caffeine can decrease the rate and the severity of BPD while the mechanisms are still unclear. The purpose of this study was to evaluate the effects of caffeine on inflammation and lung development in neonatal mice with hyperoxic lung injury and to explore the possible mechanism.

Methods

Following 14 d of 75% oxygen exposure in newborn mouse, the BPD model was established. Caffeine at a dose of 1 g/L was added in drinking water to nursing mouse. We measured the concentration of caffeine in serum and oxidative stress in lung by commercially available kits. Adenosine 2A receptor (A_2AR) expression and lung inflammation were measured by Immunohistochemistry and western blotting. Apoptosis and surfactant protein-C (SFTPC) levels were measured by immunofluorescence. The inflammasome and NF-κB pathway proteins were assessed by western blotting.

Results

We found that the caffeine concentration in plasma at present dose significantly decreased the expression of A_2AR protein in mice lung. Caffeine treatment significantly reduced oxidative stress, improved weight gain, promoted alveolar development, attenuated inflammatory infiltration and lung injury in hyperoxia-induced lung injury mice. Moreover, caffeine decreased the cell apoptosis in lung tissues, especially the Type II alveolar epithelial cell. The expression of NLRP3 inflammasome protein and NF-κB pathway were significantly inhibited by caffeine treatment.

Conclusion

Caffeine treatment can protect hyperoxia-induced mice lung from oxidative injury by inhibiting NLRP3 inflammasome and NF-κB pathway.

Diagnosis of bacterial urinary tract infection: Utility of urine myeloperoxidase concentration to predict urine culture results in dogs

Suspected bacterial urinary tract infections (UTI) are a common cause of overuse and misuse of antimicrobials. A bedside diagnostic test that could accurately predict urine culture results would prevent antimicrobial overuse, but accurate biomarkers have not yet been identified in veterinary medicine. The objective of this study was to evaluate urine myeloperoxidase (uMPO) as a rapidly available, accurate marker to predict urine culture results. We hypothesized that uMPO would be higher in dogs with a positive urine culture than in dogs with a negative urine culture, and that uMPO could be used to aid in the accurate diagnosis of significant bacteriuria. Urine samples were collected from a veterinary university clinical pathology lab. uMPO concentration was measured using a commercially available canine myeloperoxidase (MPO) enzyme-linked immunosorbent assay (ELISA). Following validation, samples from 98 dogs that had a urinalysis and urine culture performed as part of their diagnostic investigation were included. Forty-seven dogs had a negative urine culture and fifty-one dogs had a positive urine culture. uMPO levels were significantly higher in samples that had a positive culture (median 2.13 ng/ml; IQR 0.98–7.07) versus samples that had a negative culture (median 1.07 ng/ml; IQR 0.52–1.84)(p < 0.005). Based on receiver-operator characteristic, a cutoff of 0.55 ng/ml was chosen to maximize sensitivity and specificity. Using a cutoff of 0.55 ng/ml, uMPO had a sensitivity of 70% and specificity of 69% to determine the presence of a positive culture. However, the degree of overlap between groups may preclude the use of this test as a surrogate for urine culture in a clinical setting.

Levonadifloxacin, a Novel Benzoquinolizine Fluoroquinolone, Modulates Lipopolysaccharide-Induced Inflammatory Responses in Human Whole-Blood Assay and Murine Acute Lung Injury Model

Fluoroquinolones are reported to possess immunomodulatory activity; hence, a novel benzoquinolizine fluoroquinolone, levonadifloxacin, was evaluated in lipopolysaccharide-stimulated human whole-blood (HWB) and mouse acute lung injury (ALI) models. Levonadifloxacin significantly mitigated the inflammatory responses in an HWB assay through inhibition of proinflammatory cytokines and in the ALI model by lowering lung total white blood cell count, myeloperoxidase, and cytokine levels. The immunomodulatory effect of levonadifloxacin, along with promising antibacterial activity, is expected to provide clinical benefits in the treatment of infections.

Novel biomarkers for the evaluation of aging-induced proteinopathies

Proteinopathies are characterized by aging related accumulation of misfolded protein aggregates. Irreversible covalent modifications of aging proteins may significantly affect the native three dimentional conformation of proteins, alter their function and lead to accumulation of misfolded protein as dysfunctional aggregates. Protein misfolding and accumulation of aberrant proteins are known to be associated with aging-induced proteinopathies such as amyloid ß and tau proteins in Alzheimer's disease, α-synuclein in Parkinson's disease and islet amyloid polypeptides in Type 2 diabetes mellitus. Protein oxidation processes such as S-nitrosylation, dityrosine formation and some of the newly elucidated processes such as carbamylation and citrullination recently drew the attention of researchers in the field of Gerontology. Studying over these processes and illuminating their relations between proteinopathies may help to diagnose early and even to treat age related disorders. Therefore, we have chosen to concentrate on aging-induced proteinopathic nature of these novel protein modifications in this review.

Alendronate effect in esophagus, stomach and liver: an animal based pathological study

Bisphosphonates are commonly used in clinical practice. Their effectiveness is indisputable, however their adverse effects, especially in the GI tract, are still controversial. In our report, we demonstrate pathological findings of the effect of systematic alendronate administration in esophagus, stomach and the liver of an in-vivo animal model of 15 Wistar rats. Light microscopy with immunohistochemistry and electron microscopy were used. Microscopic findings of inflammation of the stomach and mild hepatic dysfunction were observed. Conclusively, alendronate can potentially affect gastric mucosa and liver function on this animal experimental model.

Anti-Inflammatory and Antioxidant Properties of the Ethanol Extract of Clerodendrum Cyrtophyllum Turcz in Copper Sulfate-Induced Inflammation in Zebrafish

Oxidative stress and inflammation are commonly present in many chronic diseases. These responses are closely related to pathophysiological processes. The inflammatory process can induce oxidative stress and vice versa through the activation of multiple pathways. Therefore, agents with antioxidant and/or anti-inflammatory activities are very useful in the treatment of many pathologies. Clerodendrum cyrthophyllum Turcz, a plant belonging to the Verbenaceae family, is used in Vietnamese traditional medicine for treating migraine, hypertension, inflammation of the throat, and rheumatic arthritis. Despite its usefulness, studies on its biological properties are still scarce. In this study, ethanol extract (EE) of leaves of C. cyrtophyllum showed protective activity against CuSO₄ toxicity. The protective activity was proven to relate to antioxidant and anti-inflammatory properties. EE exhibited relatively high antioxidant activity (IC₅₀ of 16.45 µg/mL) as measured by DPPH assay. In an in vivo anti-antioxidant test, three days post fertilization (dpf) zebrafish larvae were treated with different concentrations of EE for 1 h and then exposed to 10 µM CuSO₄ for 20 min to induce oxidative stress. Fluorescent probes were used to detect and quantify oxidative stress by measuring the fluorescent intensity (FI) in larvae. FI significantly decreased in the presence of EE at 5 and 20 µg/mL, demonstrating EE’s profound antioxidant effects, reducing or preventing oxidative stress from CuSO₄. Moreover, the co-administration of EE also protected zebrafish larvae against oxidative damage from CuSO₄ through down-regulation of hsp70 and gadd45bb expression and upregulation of sod. Due to copper accumulation in zebrafish tissues, the damage and oxidative stress were exacerbated overtime, resulting in the upregulation of genes related to inflammatory processes such as cox-2, pla2, c3a, mpo, and pro- and anti-inflammatory cytokines (il-1ß, il-8, tnf-α, and il-10, respectively). However, the association of CuSO₄ with EE significantly decreased the expression of cox-2, pla2, c3a, mpo, il-8, and il-1ß. Taken together, the results suggest that EE has potent antioxidant and anti-inflammatory activities and may be useful in the treatment of various inflammatory diseases.

Ameliorative Effect of Heat-Killed Lactobacillus plantarum L.137 and/or Aloe vera against Colitis in Mice

Inflammatory bowel disease (IBD) is one of the predominant intestinal diseases associated with chronic inflammation and ulceration of the colon. This study explored the ameliorative effect of Aloe vera extract (Aloe) and/or heat-killed Lactobacillus plantarum L.137 (HK L.137) on dextran sodium sulfate (DSS)-induced colitis in mice. Aloe and/or HK L.137 were supplied for 9 days and the mice were challenged with DSS for 7 days. The DSS group demonstrated bloody diarrhea, colitis of high histologic grade, increased nuclear factor-kappa B (NF-κB) p65, inducible nitric oxide synthase (iNOS), myeloperoxidase (MPO), interleukin (IL)-6, and tumor necrosis factor (TNF)-α, and decreased IL-10 expression. These alterations were dwindled in DSS-induced mice treated with Aloe and HK L.137 separately. Aloe and HK L.137 together have augmented the therapeutic effect of each other. In conclusion, our findings demonstrated that Aloe and/or HK L.137 ameliorated DSS-induced colitis by promoting the secretion of anti-inflammatory cytokines and suppressing pro-inflammatory mediators. This study indicated that A. vera may function synergistically with HK L.137 to confer an effective strategy to prevent colitis.

The Beneficial Effects of Antioxidants in Health And Diseases

Reactive oxygen and nitrogen species can be generated endogenously (by mitochondria, peroxisomes, and phagocytic cells) and exogenously (by pollutions, UV exposure, xenobiotic compounds, and cigarette smoke). The negative effects of free radicals are neutralized by antioxidant molecules synthesized in our body, like glutathione, uric acid, or ubiquinone, and those obtained from the diet, such as vitamins C, E, and A, and flavonoids. Different microelements like selenium and zinc have no antioxidant action themselves but are required for the activity of many antioxidant enzymes. Furthermore, circulating blood proteins are suggested to account for more than 50% of the combined antioxidant effects of urate, ascorbate, and vitamin E. Antioxidants together constitute a mutually supportive defense against reactive oxygen and nitrogen species to maintain the oxidant/antioxidant balance. This article outlines the oxidative and anti-oxidative molecules involved in the pathogenesis of chronic obstructive lung disease. The role of albumin and alpha-1 antitrypsin in antioxidant defense is also discussed.

Exercise Training Enhances Platelet Mitochondrial Bioenergetics in Stroke Patients: A Randomized Controlled Trial

Exercise training (ET) may impact physical fitness by affecting mitochondrial functions. This study aimed to elucidate the effect of ET on aerobic capacity and platelet mitochondrial bioenergetics (MTB) in stroke patients. Among the 30 stroke patients who underwent the traditional rehabilitation program (TRP), 15 were randomly assigned to have ET (50-60% VO_2peak for 30 min/day, 5 days/week for 4 weeks), and those remaining received only the TRP (control group). The peak exercise capacity (VO_2peak) and platelet MTB, including oxidative phosphorylation (OXPHOS) and the electron transport chain (ETC), were measured through automatic gas analysis and high-resolution respirometry, respectively. The results demonstrated that ET significantly increased the VO_2peak (17.7%) and O₂ uptake efficiency slope (31.9%) but decreased the ventilation versus CO₂ production slope (-7.65%). Patients who underwent ET also had significantly enhanced platelet mitochondrial OXPHOS and ETC by activating the FADH2 (Complex II)-dependent pathway, but depressed plasma myeloperoxidase (-28.4%) and interleukin-6 levels (-29.9%). Moreover, changes in VO_2peak levels were positively correlated with changes in platelet OXPHOS and ETC capacities. In conclusion, ET increases the platelet MTB by enhancing Complex II activity in stroke patients. The exercise regimen also enhances aerobic fitness and depresses oxidative stress/pro-inflammatory status in stroke patients.

Activation of the phagocyte NADPH oxidase/NOX2 and myeloperoxidase in the mouse brain during pilocarpine-induced temporal lobe epilepsy and inhibition by ketamine

Excessive reactive oxygen species (ROS) production can induce tissue injury involved in a variety of neurodegenerative disorders such as neurodegeneration observed in pilocarpine-induced temporal lobe epilepsy. Ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist has beneficial effects in pilocarpine-induced temporal lobe epilepsy, when administered within minutes of seizure to avoid the harmful neurological lesions induced by pilocarpine. However, the enzymes involved in ROS productions and the effect of ketamine on this process remain less documented. Here we show that during pilocarpine-induced epilepsy in mice, the expression of the phagocyte NADPH oxidase NOX2 subunits (NOX2/gp91^phox, p22^phox, and p47^phox) and the expression of myeloperoxidase (MPO) were dramatically increased in mice brain treated with pilocarpine. Interestingly, treatment of mice with ketamine before or after pilocarpine administration decreased this process, mainly when injected before pilocarpine. Finally, our results showed that pilocarpine induced p47^phox phosphorylation and H₂O₂ production in mice brain and ketamine was able to inhibit these processes. Our results show that pilocarpine induced NOX2 activation to produce ROS in mice brain and that administration of ketamine before or after the induction of temporal lobe epilepsy by pilocarpine inhibited this activation in mice brain. These results suggest a key role of the phagocyte NADPH oxidase NOX2 and MPO in epilepsy and identify a novel effect of ketamine.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Methyl Jasmonate Reduces Inflammation and Oxidative Stress in the Brain of Arthritic Rats

Methyl jasmonate (MeJA), common in the plant kingdom, is capable of reducing articular and hepatic inflammation and oxidative stress in adjuvant-induced arthritic rats. This study investigated the actions of orally administered MeJA (75–300 mg/kg) on inflammation, oxidative stress and selected enzyme activities in the brain of Holtzman rats with adjuvant-induced arthritis. MeJA prevented the arthritis-induced increased levels of nitrites, nitrates, lipid peroxides, protein carbonyls and reactive oxygen species (ROS). It also prevented the enhanced activities of myeloperoxidase and xanthine oxidase. Conversely, the diminished catalase and superoxide dismutase activities and glutathione (GSH) levels caused by arthritis were totally or partially prevented. Furthermore, MeJA increased the activity of the mitochondrial isocitrate dehydrogenase, which helps to supply NADPH for the mitochondrial glutathione cycle, possibly contributing to the partial recovery of the GSH/oxidized glutathione (GSSG) ratio. These positive actions on the antioxidant defenses may counterbalance the effects of MeJA as enhancer of ROS production in the mitochondrial respiratory chain. A negative effect of MeJA is the detachment of hexokinase from the mitochondria, which can potentially impair glucose phosphorylation and metabolism. In overall terms, however, it can be concluded that MeJA attenuates to a considerable extent the negative effects caused by arthritis in terms of inflammation and oxidative stress.

α-Tocopherol preserves cardiac function by reducing oxidative stress and inflammation in ischemia/reperfusion injury

OBJECTIVE

Myocardial infarction (MI) is a leading cause of mortality and morbidity worldwide and new treatment strategies are highly sought-after. Paradoxically, reperfusion of the ischemic myocardium, as achieved with early percutaneous intervention, results in substantial damage to the heart (ischemia/reperfusion injury) caused by cell death due to aggravated inflammatory and oxidative stress responses. Chronic therapy with vitamin E is not effective in reducing the cardiovascular event rate, presumably through failing to reduce atherosclerotic plaque instability. Notably, acute treatment with vitamin E in patients suffering a MI has not been systematically investigated.

METHODS AND RESULTS

We applied alpha-tocopherol (α-TOH), the strongest anti-oxidant form of vitamin E, in murine cardiac ischemia/reperfusion injury induced by ligation of the left anterior descending coronary artery for 60 min. α-TOH significantly reduced infarct size, restored cardiac function as measured by ejection fraction, fractional shortening, cardiac output, and stroke volume, and prevented pathological changes as assessed by state-of-the-art strain and strain-rate analysis. Cardioprotective mechanisms identified, include a decreased infiltration of neutrophils into cardiac tissue and a systemic anti-inflammatory shift from Ly6Chigh to Ly6Clow monocytes. Furthermore, we found a reduction in myeloperoxidase expression and activity, as well as a decrease in reactive oxygen species and the lipid peroxidation markers phosphatidylcholine (PC) (16:0)-9-hydroxyoctadecadienoic acid (HODE) and PC(16:0)-13-HODE) within the infarcted tissue.

CONCLUSION

Overall, α-TOH inhibits ischemia/reperfusion injury-induced oxidative and inflammatory responses, and ultimately preserves cardiac function. Therefore, our study provides a strong incentive to test vitamin E as an acute therapy in patients suffering a MI.

Haemolysis and lipemia interfere with resistin and myeloperoxidase BioVendor ELISA assays

Introduction

The aim of our study was to investigate the influence of haemolysis and lipemia on resistin (RES) and myeloperoxidase (MPO) measurement by BioVendor enzyme-linked immunosorbent assays (ELISA).

Materials and methods

Blood was taken from healthy volunteers into lithium heparin tubes. Plasma samples were spiked with Lipofundin® emulsion (B. Braun Melsungen AG, Germany) for lipemia interference testing. Haemolysed samples were obtained by drawing aliquots of heparinized blood through a 26 gauge needle. Index of haemolysis (H), lipemia (L) and triglyceride concentration were measured on Abbott Architect c8000. Haemoglobin concentration was measured on Sysmex XN-1000. Concentrations of RES and MPO in all samples were determined with RES and MPO ELISA kits (BioVendor, Czech Republic). All measurements were performed in triplicate. Biases from the native samples were calculated for both analytes and compared with an arbitrary value (e.g. ± 10%).

Results

Triglyceride concentration in the investigated samples ranged from 0.57 to 38.23 mmol/L, which corresponds to L index from - 0.01 to 13.77. Haemoglobin concentration in all samples ranged from 0 to 8 g/L which correspond to H index from 0.05 to 8.77. Both MPO and RES showed significant biases at 1 g/L haemoglobin (58.7% and 66.7%, respectively). Also, both MPO and RES showed significant biases at 4.66 mmol/L triglycerides (33.8% and - 12.2%, respectively).

Conclusions

Resistin BioVendor assays are affected by haemolysis and lipemia already at low degree of interferent. Haemolysis was found to interfere at 1 g/L haemoglobin for both assays, while lipemia interferes at 4.66 mmol/L of triglycerides.

Extracellular DNA, Neutrophil Extracellular Traps, and Inflammasome Activation in Severe Asthma

Rationale: Extracellular DNA (eDNA) and neutrophil extracellular traps (NETs) are implicated in multiple inflammatory diseases. NETs mediate inflammasome activation and IL-1β secretion from monocytes and cause airway epithelial cell injury, but the role of eDNA, NETs, and IL-1β in asthma is uncertain. Objectives: To characterize the role of activated neutrophils in severe asthma through measurement of NETs and inflammasome activation. Methods: We measured sputum eDNA in induced sputum from 399 patients with asthma in the Severe Asthma Research Program-3 and in 94 healthy control subjects. We subdivided subjects with asthma into eDNA-low and -high subgroups to compare outcomes of asthma severity and of neutrophil and inflammasome activation. We also examined if NETs cause airway epithelial cell damage that can be prevented by DNase. Measurements and Main Results: We found that 13% of the Severe Asthma Research Program-3 cohort is "eDNA-high," as defined by sputum eDNA concentrations above the upper 95th percentile value in health. Compared with eDNA-low patients with asthma, eDNA-high patients had lower Asthma Control Test scores, frequent history of chronic mucus hypersecretion, and frequent use of oral corticosteroids for maintenance of asthma control (all P values <0.05). Sputum eDNA in asthma was associated with airway neutrophilic inflammation, increases in soluble NET components, and increases in caspase 1 activity and IL-1β (all P values <0.001). In in vitro studies, NETs caused cytotoxicity in airway epithelial cells that was prevented by disruption of NETs with DNase. Conclusions: High extracellular DNA concentrations in sputum mark a subset of patients with more severe asthma who have NETs and markers of inflammasome activation in their airways.

The Anti-Inflammatory Role of Mannich Curcuminoids; Special Focus on Colitis

The incidence of inflammatory bowel disease (IBD) increases gradually in Western countries with high need for novel therapeutic interventions. Mannich curcuminoids, C142 or C150 synthetized in our laboratory, have been tested for anti-inflammatory activity in a rat model of TNBS (2,4,6-trinitrobenzenesulphonic acid) induced colitis. Treatment with C142 or C150 reduced leukocyte infiltration to the submucosa and muscular propria of the inflamed gut. C142 or C150 rescued the loss of body weight and C150 decreased the weight of standard colon preparations proportional with 20% less tissue oedema. Both C142 and C150 curcumin analogues caused 25% decrease in the severity of colonic inflammation and haemorrhagic lesion size. Colonic MPO (myeloperoxidase) enzyme activity as an indicator of intense neutrophil infiltration was 50% decreased either by C142 or C150 Mannich curcuminoids. Lipopolysaccharide (LPS) co-treatment with Mannich curcuminoids inhibited NF-κB (nuclear factor kappa B) activity on a concentration-dependent manner in an NF-κB-driven luciferase expressing reporter cell line. Co-treatment with LPS and curcuminoids, C142 or C150, resulted in NF-κB inhibition with 3.57 μM or 1.6 μM half maximal effective concentration (EC₅₀) values, respectively. C150 exerted a profound inhibition of the expression of inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-4 (IL-4) in human PBMCs (peripheral blood mononuclear cells) upon LPS stimulus. Mannich curcuminoids reported herein possess a powerful anti-inflammatory activity.

Delayed Initiation of Hemodialysis in Pregnant Women with Chronic Kidney Disease: Logistical Problems Impact Clinical Outcomes. An Experience from an Emerging Country

BACKGROUND

Chronic kidney disease (CKD) is associated with reduction of fertility and increased complications during pregnancy. The aim of this work is to analyze the clinical outcomes and risk factors in pregnant women who needed to start dialysis with different schedules in a public hospital in Mexico City, with particular attention on the interference of social and cultural elements as well as resource limitations.

MATERIAL AND METHODS

CKD women who needed dialysis in pregnancy over the period 2002⁻2014 and had with complete demographic and outcome data were included in this retrospective study. Clinical background, renal function during pregnancy, dialysis schedule, and clinical outcomes were reviewed.

RESULTS

Forty pregnancies in women with CKD who needed dialysis in pregnancy (39 singleton and one twin pregnancy) were studied: All patients were treated with hemodialysis. Thirty-nine patients had CKD stages 4 or 5 at referral; only one patient was of stage 3b. Dialysis was considered as indicated in the presence of fluid overload, unresponsive hypertension in the setting of advanced CKD, or when blood urea nitrogen values were increased to around 50 mg/dL. However, the initiation of dialysis was often delayed by days or weeks. The main reason for delaying the initiation of dialysis was patient (and family) refusal to start treatment. All patients were treated with thrice weekly dialysis, in 3⁻5 hour sessions, with a target urea of <100 mg/dL. The number of hours on dialysis did not impact pregnancy outcomes. Ten pregnancies ended in miscarriages (8 spontaneous), 29 in pre-term delivery, and 1 in term delivery. Fifteen women were diagnosed with preeclampsia, one with eclampsia, and one with HELLP (hemolysis, elevated liver enzymes, low platelets,) syndrome. Twenty-four of the neonates survived (77.4% of live births); six singletons and one twin died as a consequence of prematurity. Two neonates displayed malformations: cleft palate with ear anomalies and duodenal atresia.

CONCLUSIONS

CKD requiring hemodialysis in pregnancy is associated with a high frequency of complications; in the setting of delayed start and of thrice-weekly hemodialysis, dialysis schedules do not appear to influence outcomes.

Anti-inflammatory and Antioxidant Effects of Lotus corniculatus on Paracetamol-induced Hepatitis in Rats

Background: Herbal medicines have been used in the treatment of liver diseases for a long time. The current study was elaborated to evaluate in vitro and in vivo antioxidant and anti-inflammatory effects of Lotus corniculatus (L. corniculatus) butanolic extract.

Methods: The in vitro antioxidant and anti-inflammatory properties of L. corniculatus were investigated by employing DPPH radical scavenging, H₂O₂ scavenging and BSA denaturation assays. In vivo antioxidant and anti-inflammatory effects of L. corniculatus were evaluated against paracetamol (APAP)-induced hepatitis in rats. L.corniculatus at doses of 100 and 200 mg/kg was administered orally once daily for seven days. Serum transaminases (AST and ALT) and lactate dehydrogenase (LDH), total bilirubin levels, liver malondialdehyde (MDA), reduced glutathione (GSH), glutathione S- transferase (GST) and superoxide dismutase (SOD) levels and inflammatory markers, such as serum C-reactive protein (CRP), circulating and liver myeloperoxidase (MPO) levels were investigated. Further histopathological analysis of the liver sections was performed to support the effectiveness of L. corniculatus.

Results:L. corniculatus exhibited strong antioxidant and anti-inflammatory effects in vitro. In the in vivo study, our findings demonstrate that L. corniculatus (100 and 200 mg/kg) administration led to an amelioration of APAP effects on liver histology, liver functions parameters (AST, ALT, LDH, and total bilirubin levels) and liver oxidative stress markers (MDA, GSH, GST and SOD levels). Furthermore, serum CRP, circulating MPO and liver MPO levels were declined by both doses of L. corniculatus extract. The best benefits were observed with 200 mg/kg of L. corniculatus extract.

Conclusion: Antioxidant and anti-inflammatory effects of L. corniculatus extract may be due to the presence of active components.

Supplementation of Short-Chain Fatty Acid, Sodium Propionate, in Patients on Maintenance Hemodialysis: Beneficial Effects on Inflammatory Parameters and Gut-Derived Uremic Toxins, A Pilot Study (PLAN Study)

BACKGROUND

In end-stage renal disease (ESRD), gut-derived uremic toxins play a crucial role in the systemic inflammation and oxidative stress promoting the excess morbidity and mortality. The biochemical derangement is in part a consequence of an insufficient generation of short-chain fatty acids (SCFA) due to the dysbiosis of the gut and an insufficient consumption of the fermentable complex carbohydrates.

AIM OF THE STUDY

The primary end-point was to evaluate the potential efficacy of SCFA (specifically, sodium propionate (SP)) for patients on maintenance hemodialysis (MHD) on systemic inflammation. Secondary end-points included potential attenuation of oxidative stress markers, insulin resistance and production of gut-derived uremic toxins indoxyl sulfate and p-cresol sulfate, as well as health status after SP supplementation.

STUDY DESIGN

We performed a single-center non-randomized pilot study in 20 MHD patients. They received the food additive SP with a daily intake of 2 × 500 mg in the form of capsules for 12 weeks. Pre-dialysis blood samples were taken at the beginning, after six weeks and at the end of the administration period, as well as four weeks after withdrawal of the treatment.

RESULTS

The subjects revealed a significant decline of inflammatory parameters C-reactive protein (-46%), interleukin IL-2 (-27%) and IL-17 (-15%). The inflammatory parameters IL-6 and IFN-gamma showed a mild non-significant reduction and the anti-inflammatory cytokine IL-10 increased significantly (+71%). While the concentration of bacterial endotoxins and TNF-α remained unchanged, the gut-derived uremic toxins, indoxyl sulfate (-30%) and p-cresyl sulfate (-50%), revealed a significant decline. The SP supplementation reduced the parameters of oxidative stress malondialdehyde (-32%) and glutathione peroxidase activity (-28%). The serum insulin levels dropped by 30% and the HOMA-index by 32%. The reduction of inflammatory parameters was associated with a lowering of ferritin and a significant increase in transferrin saturation (TSAT). Four weeks after the end of the treatment phase, all improved parameters deteriorated again. Evaluation of the psycho-physical performance with the short form 36 (SF-36) questionnaire showed an enhancement in the self-reported physical functioning, general health, vitality and mental health. The SP supplementation was well tolerated and without important side effects. No patient had left the study due to intolerance to the medication. The SP supplementation in MHD patients reduced pro-inflammatory parameters and oxidative stress and improved insulin resistance and iron metabolism. Furthermore, SP effectively lowered the important gut-derived uremic toxins indoxyl and p-cresol sulfate. These improvements were associated with a better quality of life. Further controlled studies are required in a larger cohort to evaluate the clinical outcome.