Increased Protein Leakage Research Articles

Underlying mechanism of the microwave non-thermal effect as additional microbial inactivation on Clostridium sporogenes at pasteurization temperature level

Microwave processing can induce non-thermal effects that can inactivate additional levels of microorganisms at pasteurization temperature level (80–100 °C). The objective of this study was to investigate the mechanism behind the non-thermal effects of microwaves on vegetative cells of Clostridium sporogenes. Cell membrane damage were assessed through nuclear fluorescent dyes and by measuring nuclear acid and protein leakage. The results showed that microwave non-thermal effects and conventional water bath treatment resulted in similar nuclear acid leakage. However, microwave non-thermal effects inflicted more severe damage to the cell membranes of Clostridium sporogenes, resulting in increased protein leakage from both the inner of the cell and the cell membrane (A260 = 0.25 vs. 0.18). Consequently, it can be inferred that the inactivation of additional Clostridium sporogenes by microwave non-thermal effects is primarily attributed to the disruption of cell membranes induced by alternating electromagnetic fields, and this phenomenon is further potentiated at elevated temperatures.

Polymyxin combined with Ocimum gratissimum essential oil: one alternative strategy for combating polymyxin-resistant Klebsiella pneumoniae.

Introduction. Multidrug-resistant infections present a critical public health due to scarce treatment options and high mortality. Ocimum gratissimum L. essential oil (O.geo) is a natural resource rich in eugenol known for its antimicrobial activity.Hypothesis/Gap Statement. O.geo may exert effective antimicrobial activity against polymyxin-resistant Klebsiella pneumoniae and, when combined with Polymyxin B (PMB), may exhibit a synergistic effect, enhancing treatment efficacy and reducing antimicrobial resistance.Aim. This study aims to investigate the antimicrobial activity of O.geo against polymyxin-resistant K. pneumoniae using in vitro tests and an in vivo Caenorhabditis elegans model.Methodology. The O.geo was obtained by hydrodistillation followed by gas chromatography. The MIC and antibiofilm activity were determined using broth microdilution. Checkerboard and time-kill assays evaluated the combination of O.geo and polymyxin B (PMB), whereas a protein leakage assay verified its action.Results. Eugenol (39.67%) was a major constituent identified. The MIC of the O.geo alone ranged from 128 to 512 µg ml-1. The fractional inhibitory concentration index (0.28) and time-kill assay showed a synergism. In addition, O.geo and PMB inhibited biofilm formation and increased protein leakage in the plasma membrane. The treatment was tested in vivo using a Caenorhabditis elegans model, and significantly increased survival without toxicity was observed.Conclusion. O.geo could be used as a potential therapeutic alternative to combat infections caused by multidrug-resistant bacteria, especially in combination with PMB.

Green synthesis of TiO2 nanoparticles using Terminalia chebula and its potent antibiofilm activity against dental caries-associated bacterium Streptococcus mutans

The production of eco-friendly nanoparticles with biocompatible properties is gaining prominence in global medical research. In this study, we explore the antibiofilm potential of Titanium dioxide nanoparticles (TiO2NPs) synthesized from Terminalia chebula against the oral pathogen Streptococcus mutans. Characterization of TiO2NPs revealed a UV–Vis peak at 322 nm. FT-IR spectrum identified Ti–O–Ti vibrations, hydroxyl, and carboxylic groups. SEM analysis revealed tetragonal TiO2NPs, with EDX confirming titanium. XRD confirmed TiO2 anatase crystallographic planes at 25.8° with an average grain size of the particle of 56 nm. Biofilm inhibitory activity indicated significant inhibition of biofilm with BIC50 of 65.71 μg/ml. Microscopic visualization substantiated the efficiency of TiO2NPs in impeding biofilm formation. Increased TiO2NPs concentrations showed a marked reduction in exopolysaccharide and increased protein leakage from S. mutans after prolonged exposure. These findings suggest TiO2NPs as potential agents for treating dental caries, though further validation is needed for therapeutic use in oral care.

AN AYURVEDIC APPROACH TO MANAGING NEPHROTIC SYNDROME: RESTORING BALANCE AND RENAL HEALTH

Nephrotic syndrome is a chronic kidney disorder characterized by increased protein leakage in the urine, swell-ing, and low levels of proteins in the blood. The conventional medical approach to managing nephrotic syn-drome focuses primarily on symptom management and immune suppression. However, Ayurveda, an ancient holistic system of medicine, offers a comprehensive approach that addresses the underlying imbalances and aims to restore renal health. This article explores the Ayurvedic perspective on nephrotic syndrome and provides in-sights into the principles and treatment strategies employed in Ayurvedic medicine. The Ayurvedic understand-ing of nephrotic syndrome revolves around the concept of dosha imbalance, particularly Vata and Kapha dosha. Imbalances in these doshas are believed to disrupt the normal functioning of the kidneys, leading to the manifes-tation of nephrotic syndrome symptoms. Ayurvedic treatment for nephrotic syndrome involves a combination of dietary and lifestyle modifications, herbal remedies, detoxification procedures, and rejuvenation therapies. Spe-cific herbs and herbal formulations are utilized to support kidney function, reduce protein leakage, and promote the regeneration of damaged renal tissues. Additionally, dietary recommendations focus on balancing the doshas, reducing inflammation, and promoting overall kidney health. Furthermore, the article highlights the importance of personalized Ayurvedic treatment, as the management of nephrotic syndrome may vary depending on an indi-vidual's constitution, imbalances, and stage of the disease. The holistic approach of Ayurveda aims to not only alleviate symptoms but also prevent disease recurrence and enhance the overall well-being of the individual. In conclusion, this article provides valuable insights into the Ayurvedic approach to managing nephrotic syndrome. By addressing the root cause of the condition and employing individualized treatment strategies, Ayurveda offers a promising alternative or complementary option for individuals seeking a holistic and natural approach to renal health. Further research and clinical studies are warranted to validate the efficacy of Ayurvedic interventions in the management of nephrotic syndrome.

Molecular insights into the antifungal activity of biosynthesized Ag-ZnO hybrid nanostructures against Schizosaccharomyces pombe

Biosynthesized Ag-ZnO nanohybrids were characterized by TEM, HRTEM, FESEM, EDX and Raman spectroscopy. Bullet-like ZnO nanostructures with a mean size ∼ 48 nm were revealed by FESEM and TEM analyses, which were decorated with Ag nanoparticles with a mean size of ∼ 18 nm. Raman analysis showed that nanohybrids consisted of hexagonal wurtzite ZnO. We next tested the impact of these Ag-ZnO hybrid nanostructures on growth of Schizosaccharomyces pombe. It was observed that these hybrid nanoparticles exhibited strong antifungal activity against Schizosaccharomyces pombe, and effectively inhibited S. pombe growth at 100 µg/mL. To gain insights into the mechanism of action underlying the antifungal activity of these Ag-ZnO nanohybrids, various biochemical and molecular assays were carried out. Result of these assays revealed that treatment with the Ag-ZnO nanohybrids resulted in accumulation of reactive oxygen species (ROS) in S. pombe. Moreover, DNA fragmentation, increased lipid peroxidation, and increased protein leakage were observed in Ag-ZnO nanohybrids treated S. pombe. Taken together, the antifungal action of nanohybrids of Ag-ZnO against S. pombe can mainly be attributed to ROS triggered oxidative stress, which further causes increased lipid peroxidation, and cell membrane damage resulting in protein leakage as well as DNA fragmentation.

Antibacterial mechanism of lactobionic acid against Shewanella baltica and Shewanella putrefaciens and its application on refrigerated shrimp

Lactobionic acid (LBA) is a novel antibacterial agent that has attracted much interest in recent years. However, the study on the antibacterial effect of LBA on spoilage bacteria is rare. This study aims to investigate the antibacterial activity and mechanism of LBA on Shewanella baltica and Shewanella putrefaciens, which are the common spoilage microorganisms in chilled seafood. The results demonstrated that LBA was an effective bacteriostat against S. baltica and S. putrefaciens, with the minimum inhibitor concentration (MIC) of 8 mg/mL. Both the two Shewanella species could be completely killed by LBA at 2 MIC. LBA damaged the cell membrane integrity and increased outer membrane permeability, causing the increase in protein leakage and conductivity, which was supported by the bacterial morphology observed with scanning electron microscopy. Besides, LBA could interact with the bacterial genome DNA, resulting in the dysfunction of cell function. Moreover, LBA exhibited an effectively inhibitory effect on slowing down microbial growth, melanosis and lipid oxidation rate in refrigerated shrimp. These results suggest that LBA would be a promising antibacterial compound used in seafood.

Increased Heparanase Levels in Urine during Acute Puumala Orthohantavirus Infection Are Associated with Disease Severity.

Old–world orthohantaviruses cause hemorrhagic fever with renal syndrome (HFRS), characterized by acute kidney injury (AKI) with transient proteinuria. It seems plausible that proteinuria during acute HFRS is mediated by the disruption of the glomerular filtration barrier (GFB) due to vascular leakage, a hallmark of orthohantavirus–caused diseases. However, direct infection of endothelial cells by orthohantaviruses does not result in increased endothelial permeability, and alternative explanations for vascular leakage and diminished GFB function are necessary. Vascular integrity is partly dependent on an intact endothelial glycocalyx, which is susceptible to cleavage by heparanase (HPSE). To understand the role of glycocalyx degradation in HFRS–associated proteinuria, we investigated the levels of HPSE in urine and plasma during acute, convalescent and recovery stages of HFRS caused by Puumala orthohantavirus. HPSE levels in urine during acute HFRS were significantly increased and strongly associated with the severity of AKI and other markers of disease severity. Furthermore, increased expression of HPSE was detected in vitro in orthohantavirus–infected podocytes, which line the outer surfaces of glomerular capillaries. Taken together, these findings suggest the local activation of HPSE in the kidneys of orthohantavirus–infected patients with the potential to disrupt the endothelial glycocalyx, leading to increased protein leakage through the GFB, resulting in high amounts of proteinuria.

Inhibitory effects of lactobionic acid on Vibrio parahaemolyticus planktonic cells and biofilms

Vibrio parahaemolyticus is the primary pathogenic bacteria associated with seafood-borne illnesses. Lactobionic acid (LBA) is an organic acid with multiple biological activities that has recently been a focus of interest as an antibacterial agent. The aim of this study was to investigate the inhibitory effects of LBA on Vibrio parahaemolyticus planktonic cells and biofilms. The minimum inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of LBA against Vibrio parahaemolyticus were both identified as 4 mg/mL. LBA exerted antimicrobial effects against planktonic Vibrio parahaemolyticus cells by damaging their membranes, as revealed by reduced intracellular ATP concentrations, increased protein leakage, abnormal cell morphology and diminished membrane integrity after treatment. At 1/16 × MIC and 1/8 × MIC, LBA inhibited biofilm formation and downregulated the expression of some biofilm-related genes, which was confirmed by crystal violet staining, field-emission scanning electron microscopy (FESEM) observations, and real-time quantitative PCR analysis. Moreover, LBA inactivated Vibrio parahaemolyticus cells within biofilms (on polystyrene and stainless steel surfaces), destroyed biofilm structures on stainless steel surfaces, and also reduced the levels of polysaccharides and proteins in the biofilms. Therefore, LBA is a potential low-cost agent that can be used to control planktonic Vibrio parahaemolyticus and its biofilms.

Differential Lung Responses to Early Life Ozone Exposure in Male and Female Rat Offspring

The role that early life events (intrauterine growth restriction) and environmental exposures (air pollution) play in development of childhood asthma are only partly understood. We previously showed that exposure of Long‐Evans rats to the oxidant air pollutant ozone (O3) on gestational days (GD) 5 and 6; 0.8 ppm x 4h] resulted in growth restriction at GD21. The aim of this study was to determine whether gestational ± repeated peri‐adolescent O3‐exposure of offspring (0.4–0.8 ppm x 4h; once/week at 5, 6, and 7 weeks‐of‐age) would alter lung growth or acute ventilatory response to O3 exposure.Immediately post‐exposure (0h), baseline (BL) spontaneous ventilation [i.e., breathing frequency (f), tidal volume (TV), and PenH, a unitless parameter suggestive of bronchoconstriction] were obtained using whole body plethysmography (WBP) with EMKA iox 2 software (SCIREQ, Montreal, CANADA) followed by a 6‐min 6%‐CO2 challenge to enhance tidal breathing. At 4h, the left lung lobe was fixed (at 20 cm H2O) for volume displacement and histology. Right lobes were lavaged to assessed lung injury and inflammation. Two‐way ANOVAs were used to assess male (M) and female (F) responses separately; O3‐exposed groups were compared to Air‐exposed dams + postnatal (PN)‐Airx3)].By week 7, in males, dam O3‐exposure resulted in augmented body “height” (skull base‐to‐tail head); but not body weight or weight adjusted by height (gm/cm). In females, PN‐O3x3 exposure was associated with reduced weight/height. By the 3rd PN exposure, both M & F O3‐exposed rats continued to exhibit some degree of dyspnea at 0h, with corresponding increases in BL Penh (F: 5.2–5.6 fold, M: 3.9–4.8 fold). Significant reduction in BL TVcorr (corrected for “height”) was apparent only in F O3+O3x3 rats. CO2 challenge increased breathing frequency in all rats, and F rats were more responsive in terms of enhanced TV increases (A+Ax3 and O3+Ax3 offspring increased 56 and 68%, respectively). M A+Ax3 and O3+Ax3‐exposed rats increased 45%. By contrast, O3‐exposed F A+O3x3 and O3+O3x3 rats only had 25 and 40% increases, respectively; while M A+O3x3 and O3+O3x3 rats increased 24%. Based on enhanced TVcorr, values, both M and F O3‐exposed offspring developed a “classic” short‐and‐shallow respiratory pattern acutely following exposure. In F but not M offspring, CO2‐enhanced TV was inversely correlated with PenH. WBP parameters returned to BL within 2–4 minutes of CO2 discontinuation. At necropsy, dam O3‐exposure was associated with lower lung (fixed) volumes in females. For both sexes, lung injury (increased protein leakage) and inflammation (neutrophils and cytokines in lavage fluid) were increased chiefly by PN‐O3 exposure. Protein leakage increased proportionately with PenH. Histopathologic changes are currently being analyzed.In summary, female offspring, especially O3+O3x3 rats appear to have differences in lung function growth and acute O3 responses. The 6‐min 6%‐CO2 protocol was well tolerated and increased TV to approximately 50% of a maximal breath (FEV1). This approach may provide a sensitive, yet non‐invasive method to document differential lung growth trajectories in rodent models of early life stressors. (Abstract does not reflect USEPA policy).Support or Funding InformationEPA funding; A‐E and SHC programs

Antibacterial activity of buckwheat honey added with ferrous lactate against Pseudomonas aeruginosa

Hydroxyl radical (OH∙) in honey has been identified to cause damage to bacteria that degrades DNA, stalls growth and even kills cells. This study investigated the action model of OH∙ induced by exogenous ferrous iron. Our data showed that ferrous lactate augmented the antibacterial activity of buckwheat honey by producing OH∙ that targeted at components in the respiratory system and the metabolic system such as NADH dehydrogenases and 6-phosphogluconate dehydratases in Pseudomonas aeruginosa. After buckwheat honey was pretreated with ferrous lactate, the activities of NADH dehydrogenases and 6-phosphogluconate showed 79.9% and 99.7% reduction respectively. Activities of these enzymes were much less affected if OH∙ was scavenged by α-tocopherol. OH∙ in buckwheat honey also increased malondialdehyde production from 0.54 to 6.87 nmoL/g and seriously damaged the cell membrane in P. aeruginosa. This damage ramped up the membrane permeability and increased protein leakage from 0.02 to 1.87 μg/mg. Our results indicate that in such action model exogenous ferrous lactate brings on cell decomposition and increases bactericidal activity of buckwheat honey.

SAT-262 Differential Metabolic, Thermal, and Pulmonary Responses to Early Life Ozone Exposure in Male and Female Rats

The essential role that early life events (i.e., intrauterine growth restriction) and environmental exposures (i.e., air pollution) play in development of childhood asthma and obesity are only partly understood. Notably, asthmatic children who develop obesity through adolescence have poorer disease outcomes. In our previous studies we showed that exposure of Long-Evans rats to the oxidant air pollutant, ozone (O3), during implantation [gestational days (GD) 5 and 6; 0.8 ppm x 4h] resulted in growth restriction at GD21. The aims of this study were to determine whether gestational ± repeated peri-adolescent O3-exposure (0.4-0.8 ppm x 4h; once/week at 5, 6, and 7 weeks-of-age) would alter offspring metabolism, body, or lung growth, and acute thermal or pulmonary responses to O3. Using 2-way ANOVA with Dunnett’s post hoc correction, responses in males (M) and females (F) were evaluated separately; all O3-exposed groups were compared to controls [air-exposed dams + PN-Air-(x3)] of the corresponding sex. By postnatal (PN) day 45, results showed that in males, dam O3-exposure was associated with augmented body “height” (skull base-to-tail head) and increases in serum triglyceride, and cholesterol levels; but not body weight, weight adjusted by height (gm/cm), or corrected lung (fixed) volume (mL/cm height x100%). PN-O3x3 exposures were associated with increased HOMA-IR ratios and further increases in cholesterol. In females, dam O3-exposure was associated with lower lung volumes and increased serum cholesterol; while PN-O3x3 exposure was associated with reduced weight/height (gm/cm). For both sexes, the degree of acute hypothermia was altered in association with both dam- and especially PN-O3 exposures; whereas lung injury (e.g., increased protein leakage) and inflammation (e.g., neutrophils) in lung lavage fluid, were increased chiefly by PN-O3 exposure. Particularly in males, lesser inflammatory responses were observed in O3+O3x3 rats (e.g., reduced KC-GRO and IL-6 cytokine levels) compared to Air+O3x3 rats. Conversely, lavage fluid TNFα concentrations were increased only in the O3+O3x3 males. Taken together, data suggest that O3 exposure during gestation played a greater role in predisposing offspring to dyslipidemia, whereas peri-adolescent exposure dominated the acute hypothermia and inflammatory responses. Importantly, males exposed to both gestational and postnatal O3 appeared to (A) develop greater dyslipidemia (a precursor of metabolic syndrome) and (B) altered lung innate inflammatory responses − potentially influencing TH-1 to TH-2 balance (a precursor to allergic asthma) later in life. (This abstract does not reflect USEPA policy).

Antimicrobial Photothermal Treatment of Pseudomonas Aeruginosa by a Carbon Nanoparticles-Polypyrrole Nanocomposite.

Background: Nowadays, it is needed to explore new routes to treat infectious bacterial pathogens due to prevalence of antibiotic-resistant bacteria. Antimicrobial photothermal therapy (PTT), as a new strategy, eradicates pathogenic bacteriaObjective: In this study, the antimicrobial effects of a carbon nanoparticles-polypyrrole nanocomposite (C-PPy) upon laser irradiation were investigated to destroy the pathogenic gram-negative Pseudomonas aeruginosa.Material and Methods: In this experimental study, the bacterial cells were incubated with 50, 100 and 250 µg mL-1 concentrations of C-PPy and irradiated with a 808-nm laser at two power densities of 0.5 and 1.0 W cm-2. CFU numbers were counted for the irradiated cells, and compared to an untreated sample (kept in dark). To explore the antibacterial properties and mechanism(s) of C-PPy, temperature increment, reactive oxygen species formation, and protein and DNA leakages were evaluated. Field emission scanning electron microscopy was also employed to investigate morphological changes in the bacterial cell structures.Results: The results showed that following C-PPy attachment to the bacteria surface, irradiation of near-infrared light resulted in a significant decrement in the bacterial cell viability due to photothermal lysis. Slightly increase in protein leakage and significantly increase intracellular reactive oxygen species (ROS) were observed in the bacteria upon treating with C-PPy.Conclusion: Photo-ablation strategy is a new minimally invasive and inexpensive method without overdose risk manner for combat with bacteria

Chronic hypersensitivity pneumonitis caused by Saccharopolyspora rectivirgula is not associated with a switch to a Th2 response.

Hypersensitivity pneumonitis (HP) is an immune-mediated interstitial lung disease that develops following repeated exposure to inhaled environmental antigens. The disease results in alveolitis and granuloma formation and may progress to a chronic form associated with fibrosis; a greater understanding of the immunopathogenic mechanisms leading to chronic HP is needed. We used the Saccharopolyspora rectivirgula (SR) mouse model of HP to determine the extent to which a switch to a Th2-type immune response is associated with chronic HP. Exposure of wild-type (WT) and tlr2/9(-/-) mice to SR for 14 wk resulted in neutrophilic and lymphocytic alveolitis that was not dependent on Toll-like receptors (TLRs) 2 and 9. Long-term exposure of WT mice to SR resulted in a significant increase in collagen deposition, protein leakage, and IL-1α accompanied by a decrease in quasistatic compliance and total lung capacity compared with unexposed mice. This was associated with an increase in IL-17 but not IL-4 production or recruitment of Th2 cells. tlr2/9(-/-) mice exhibited an increase in protein leakage but less IL-1α and collagen deposition in the lungs compared with WT mice, yet they still displayed a decrease in quasistatic compliance, although total lung capacity was not affected. These mice exhibited an increase in both IL-13 and IL-17, which suggests that IL-13 may ameliorate some of the lung damage caused by long-term SR exposure. Our results suggest that lung pathology following long-term SR exposure in WT mice is associated with the IL-17 response and that TLRs 2 and 9 may inhibit the development of the IL-13/Th2 response.

Increased Endothelial Cell-Leukocyte Interaction in Murine Schistosomiasis: Possible Priming of Endothelial Cells by the Disease

Background and AimsSchistosomiasis is an intravascular parasitic disease associated with inflammation. Endothelial cells control leukocyte transmigration and vascular permeability being modulated by pro-inflammatory mediators. Recent data have shown that endothelial cells primed in vivo in the course of a disease keep the information in culture. Herein, we evaluated the impact of schistosomiasis on endothelial cell-regulated events in vivo and in vitro.Methodology and Principal FindingsThe experimental groups consisted of Schistosoma mansoni-infected and age-matched control mice. In vivo infection caused a marked influx of leukocytes and an increased protein leakage in the peritoneal cavity, characterizing an inflamed vascular and cellular profile. In vitro leukocyte-mesenteric endothelial cell adhesion was higher in cultured cells from infected mice as compared to controls, either in the basal condition or after treatment with the pro-inflammatory cytokine tumor necrosis factor (TNF). Nitric oxide (NO) donation reduced leukocyte adhesion to endothelial cells from control and infected groups; however, in the later group the effect was more pronounced, probably due to a reduced NO production. Inhibition of control endothelial NO synthase (eNOS) increased leukocyte adhesion to a level similar to the one observed in the infected group. Besides, the adhesion of control leukocytes to endothelial cells from infected animals is similar to the result of infected animals, confirming that schistosomiasis alters endothelial cells function. Furthermore, NO production as well as the expression of eNOS were reduced in cultured endothelial cells from infected animals. On the other hand, the expression of its repressor protein, namely caveolin-1, was similar in both control and infected groups.Conclusion/SignificanceSchistosomiasis increases vascular permeability and endothelial cell-leukocyte interaction in vivo and in vitro. These effects are partially explained by a reduced eNOS expression. In addition, our data show that the disease primes endothelial cells in vivo, which keep the acquired phenotype in culture.

Mechanical ventilation aggravates transfusion-related acute lung injury induced by MHC-I class antibodies

Transfusion-related acute lung injury (TRALI) occurs more often in critically ill patients than in a general hospital population, possibly due to the presence of underlying inflammatory conditions that may prime pulmonary neutrophils. Mechanical ventilation may be a risk factor for developing TRALI. We examined the influence of mechanical ventilation (MV) on the development of TRALI, combining a murine MV model causing ventilator-induced lung injury with a model of antibody-induced TRALl. BALB/c mice (n = 84) were ventilated for 5 h with low (7.5 ml/kg) or high (15 ml/kg) tidal volume, a positive end-expiratory pressure of 2 cm H(2)O and a fraction of inspired oxygen of 50%. After 3 h of MV, TRALI was induced by infusion of MHC-I antibodies (4.5 mg/kg); controls received vehicle. Non-ventilated animals receiving vehicle, isotype or MHC-I antibodies served as additional controls. All animals receiving MHC-I antibodies developed TRALI within 2 h. In mice in which TRALI was induced, MV with low tidal volumes aggravated pulmonary injury, as evidenced by an increase in neutrophil influx, pulmonary and systemic levels of cytokines and lung histopathological changes compared to unventilated controls. The use of high tidal volume ventilation resulted in a further increase in protein leakage and pulmonary edema. Mechanical ventilation (MV) synergistically augmented lung injury during TRALI, which was even further enhanced by the use of injurious ventilator settings. Results suggest that MV may be a risk factor for the onset of TRALI and may aggravate the course of disease.

Decreased Nephrin and GLEPP-1, But Increased VEGF, Flt-1, and Nitrotyrosine, Expressions in Kidney Tissue Sections From Women With Preeclampsia

Renal injury is a common pathophysiological feature in women with preeclampsia as evidenced by increased protein leakage (proteinuria) and glomerular injury (glomerular endotheliosis). Recently, podocyturia was found in preeclampsia, suggesting podocyte shedding occurs in this pregnancy disorder. However, podocyte function in preeclampsia is poorly understood. In this study, the authors have examined podocyte-specific protein expressions for nephrin, glomerular epithelial protein 1 (GLEPP-1), and ezrin in kidney biopsy tissue sections from women with preeclampsia. Expressions for vascular endothelial growth factor (VEGF) and its receptor Flt-1 and oxidative stress marker nitrotyrosine and antioxidant CuZn-superoxide dismutase (CuZn-SOD) were also examined. Kidney tissue sections from nonhypertensive and chronic hypertensive participants were stained as controls. The findings were (1) nephrin and GLEPP-1 were mainly expressed in glomerular podocytes; (2) ezrin was expressed in both glomerular podocytes and tubular epithelial cells; (3) compared to tissue sections from nonhypertensive and chronic hypertensive participants, nephrin and GLEPP-1 expressions were much reduced in tissue sections from preeclampsia and ezrin expression was reduced in podocytes; (4) enhanced VEGF, Flt-1, and nitrotyrosine, but reduced CuZn-SOD, expressions were observed in both glomerular podocytes and endothelial cells in tissue sections from preeclampsia; and (5) the expression pattern for nephrin, GLEPP-1, ezrin, VEGF, Flt-1, and CuZn-SOD were similar between tissue sections from nonhypertensive and chronic hypertensive participants. Although the authors could not conclude from this biopsy study whether the podocyte injury is the cause or effect of the preeclampsia phenotype, the data provide compelling evidence that podocyte injury accompanied by altered angiogenesis process and increased oxidative stress occurs in kidney of patients with preeclampsia.

Hypertension-induced protein leakage in the brain in ethanol-intoxicated conscious and anesthetized rats

Ethanol has been shown to aggravate the blood-brain barrier (BBB) dysfunction in cerebral trauma and in cerebral gas embolism, possibly by changing the endothelial cell membrane. No difference in protein extravasation was found between intoxicated and control rats under nitrous oxide anesthesia after the injection of bicuculline, a drug that hemodynamically gives rise to high blood pressure in combination with cerebral vasodilatation. In contrast there was a statistically significant increase in protein leakage in conscious intoxicated rats. The fact that ethanol increased the vulnerability only in conscious rats might indicate that nitrous oxide and ethanol have a common effect on the endothelial cell membranes or that nitrous oxide neutralizes an action of ethanol. Protein leakage induced by acute hypertension is more severe in rats anesthetized with nitrous oxide than in conscious rats, a difference that might to some extent be related to an effect of nitrous oxide on the endothelial cells. Further studies are needed to evaluate the influence of ethanol and nitrous oxide on the endothelial cell membrane.

Heparan Sulfate Plays a Central Role in a Dynamic in Vitro Model of Protein-losing Enteropathy

Protein-losing enteropathy (PLE), the loss of plasma proteins through the intestine, is a symptom in ostensibly unrelated diseases. Emerging commonalities indicate that genetic insufficiencies predispose for PLE and environmental insults, e.g. viral infections and inflammation, trigger PLE onset. The specific loss of heparan sulfate (HS) from the basolateral surface of intestinal epithelial cells only during episodes of PLE suggests a possible mechanistic link. In the first tissue culture model of PLE using a monolayer of intestinal epithelial HT29 cells, we proved that HS loss directly causes protein leakage and amplifies the effects of the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha). Here, we extend our in vitro model to assess the individual and combined effects of HS loss, interferon gamma (IFNgamma), TNFalpha, and increased pressure, and find that HS plays a central role in the patho-mechanisms underlying PLE. Increased pressure, mimicking venous hypertension seen in post-Fontan PLE patients, substantially increased protein leakage, but HS loss, IFNgamma, or TNFalpha alone had only minor effects. However, IFNgamma up-regulated TNFR1 expression and amplified TNFalpha-induced protein leakage. IFNgamma and TNFalpha compromised the integrity of the HT29 monolayer and made it more susceptible to increased pressure. HS loss itself compromises the integrity of the monolayer, amplifying the effects of pressure, but also amplifies the effects of both cytokines. In the absence of HS a combination of increased pressure, IFNgamma, and TNFalpha caused maximum protein leakage. Soluble heparin fully compensated for HS loss, providing a reasonable explanation for patient favorable response to heparin therapy.

The Fate of Antioxidant Enzymes in Bronchoalveolar Lavage Fluid Over 7 Days in Mice with Acute Lung Injury

Characterization of lung injury is important if timely therapeutic intervention is to be used properly and successfully. In this study, lung injury was defined as the progressive formation of pulmonary edema. Our model gas was phosgene, a pulmonary edemagenic compound. Phosgene, widely used in industry, can produce life-threatening pulmonary edema within hours of exposure. Four groups of 40 CD-1 male mice were exposed whole-body to either air or a concentration × time (c × t) amount of 32-42 mg/m 3 (8-11 ppm) phosgene for 20 min (640-840 mg·min/m 3) . Groups of air- or phosgene-exposed mice were euthanized 1, 4, 8, 12, 24, 48, or 72 h or 7 days postexposure. The trachea was excised, and 800 µl saline was instilled into the lungs and washed back and forth 5 times to collect bronchoalveolar lavage fluid (BALF). The antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), total glutathione (GSH), and protein were determined at each time point. Phosgene exposure significantly enhanced both GPx and GR in phosgene-exposed mice compared with air-exposed mice from 4 to 72 h, p ≤ .01 and p ≤ .005, respectively. BALF GSH was also significantly increased, p ≤ .01, from 4 to 24 h after exposure, in comparison with air-exposed. BALF protein, an indicator of air/blood barrier integrity, was significantly higher than in air-exposed mice 4 h to 7 days after exposure. In contrast, BALF SOD was reduced by phosgene exposure from 4 to 24 h, p ≤ .01, versus air-exposed mice. Except for protein, all parameters returned to control levels by 7 days postexposure. These data indicate that the lung has the capacity to repair itself within 24-48 h after exposure by reestablishing a functional GSH redox system despite increased protein leakage. SOD reduction during increased leakage may indicate that barrier integrity is affected by superoxide anion production.

The Fate of Antioxidant Enzymes in Bronchoalveolar Lavage Fluid Over 7 Days in Mice with Acute Lung Injury

Characterization of lung injury is important if timely therapeutic intervention is to be used properly and successfully. In this study, lung injury was defined as the progressive formation of pulmonary edema. Our model gas was phosgene, a pulmonary edemagenic compound. Phosgene, widely used in industry, can produce life-threatening pulmonary edema within hours of exposure. Four groups of 40 CD-1 male mice were exposed whole-body to either air or a concentration × time (c × t) amount of 32-42 mg/m 3 (8-11 ppm) phosgene for 20 min (640-840 mg·min/m 3) . Groups of air- or phosgene-exposed mice were euthanized 1, 4, 8, 12, 24, 48, or 72 h or 7 days postexposure. The trachea was excised, and 800 µl saline was instilled into the lungs and washed back and forth 5 times to collect bronchoalveolar lavage fluid (BALF). The antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), total glutathione (GSH), and protein were determined at each time point. Phosgene exposure significantly enhanced both GPx and GR in phosgene-exposed mice compared with air-exposed mice from 4 to 72 h, p ≤ .01 and p ≤ .005, respectively. BALF GSH was also significantly increased, p ≤ .01, from 4 to 24 h after exposure, in comparison with air-exposed. BALF protein, an indicator of air/blood barrier integrity, was significantly higher than in air-exposed mice 4 h to 7 days after exposure. In contrast, BALF SOD was reduced by phosgene exposure from 4 to 24 h, p ≤ .01, versus air-exposed mice. Except for protein, all parameters returned to control levels by 7 days postexposure. These data indicate that the lung has the capacity to repair itself within 24-48 h after exposure by reestablishing a functional GSH redox system despite increased protein leakage. SOD reduction during increased leakage may indicate that barrier integrity is affected by superoxide anion production.