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Is Oxidized Albumin, a Mediator and a Biomarker of Systemic Inflammation in Diabetic Nephropathy?
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revealed, that MLP mice exhibit a reduction of fractional -/shortening (FS, FVB/N wildtype vs. MLP : 24.243 ± 1.522 vs. 11.384 ± 1.096, p<0.001) and ejection fraction (EF, FVB/N -/wildtype vs. MLP : 48.448 ± 2.509 vs. 24.731 ± 2.278, p<0.001) compared to FVB/N wildtype, as expected. Remarkably, application of OA-NO2 led to a significant attenuation of the reduction of these parameters (vehicle vs. OA-NO2, FS: 11.384 ± 1.096 vs. 17.62 ± 1.101, p<0.01; EF: 24.731 ± 2.278 vs. 36.755 ± 2.003, p<0.01) resulting in an improvement of left ventricular function. Dihydroethidine staining of ventricular sections showed an attenuation of ROS production in hearts of OA-NO2 treated -/mice compared to elevated levels in vehicle treated MLP mice. Furthermore, we observed a positive effect of OA-NO2 on the contractility force and velocity using engineered heart tissue (EHT). Beyond that OA-NO2 significantly improved endothelial function (% of relaxation to 100 nM Ach treatment, FVB/N -/-/wildtype vs. MLP vs. MLP + OA-NO2, -67.22 ± 1.92 vs. -37.51 ± 3.83 vs. -53.98 ± 3.11, p<0.001) Conclusions: The current results reveal an improvement of endothelial and left ventricular function by application of OA-NO2 in a mouse model of DCM. If this effect is related to an improvement of the contractility on the single cell level or to an advancement of the vascular function still has to be determined. Nevertheless, in addition to the known anti-inflammatory properties of nitrated fatty acids, these results strongly corroborate the cardioprotective potential of nitrated fatty acids.
doi:10.1016/j.freeradbiomed.2012.10.232
177 Redox Imbalance Activates High Mobility Group Box Protein 1 Which Modulates T Cells Phenotype and Cytokine Profile in Depressed Patients. the Impact on Glucocorticoids Response. 1,2
Joanna Rybka , Kornelia Kedziora-Kornatowska1, Daria Kupczyk1, and Jozef Kedziora1 1 2 Collegium Medicum in Bydgoszcz, Poland Scienceventure Joanna Rybka, Poland Background: High- mobility group protein B1 (HMGB1) is redox sensitive inflammatory mediator acting as an effective stimulus triggering the inflammatory response. Objectives: We aimed to study HMGB1, pro- and antioxidant status alongside with T cells phenotype and Th1 and Th17 proinflammatory cytokine profiles in depressed patient. We also investigated the glucocorticoid response in relation to oxidative and inflammatory status. Methods: Blood was collected from patients diagnosed with recurrent depressive disorder (rDD) (N=15) and from healthy controls (N=19). We measured plasma hydrogen peroxide (H2O2), superoxide generation by zymosan stimulated neutrophils, reduced glutathione (GSH) and malondialdehyde (MDA) levels. Furthermore, SOD1, GPx, GR activities in red blood cells and HO1 and NOX4 levels in plasma were assessed in this study. IL2, IL-6, IL-8, IFN-γ, TNF-α, IL-17, HMGB1, neopterin and cortisol were assayed immunoenzymatically in sera. Surface phenotype expression of T regulatory and T effector cells were also investigated. The glucocorticoid response was measured by dexamethasone-induced inhibition of IL-6 produced by LPSstimulated peripheral blood. Results: We observed pro- and antioxidant imbalance in depressed patients expressed by significant changes in the enzyme activities, increased MDA, decreased GSH, increased H2O2, decreased neutrophils superoxide generation. Shifted Th1/Th17 cytokine ratios, increased Treg/Teffector cells ratio and increased levels of neopterin were also detected. Moreover, we
S78
revealed a distinct role of HMGB1 in maintaining cytokine and Treg/Teffector cells balance in depressed patients. HMGB1 remained also in relation with oxidant potential of the blood. The important role of IL-17 and inhibitory effect of MDA on glucocorticoids response was also revealed. Conclusions: Strong immunomodulatory role of HMGB1 might be related to the change of its activity caused by redox imbalance in depressed patients. The shifted immune balance alongside with prooxidative environment modulates glucocorticoid response in these patients.
doi:10.1016/j.freeradbiomed.2012.10.233
178 Is Oxidized Albumin, a Mediator and a Biomarker of Systemic Inflammation in Diabetic Nephropathy?
Regina Michelis1, Batya Kristal1,2, Galina Shapiro1, Yoav Fridman1, 1,2 Teuta Zeitun1, Ronit Geron1, and Shifra Sela 1 2 Western Galilee Hospital, Israel, Bar Ilan University, Israel Background: Hypoalbuminemia, Oxidative Stress (OS) and systemic inflammation are common in patients with diabetic nephropathy (DN). Oxidative modifications of serum albumin were shown to impair its quantification by the bromocresol-green assay (BCG) in patients on hemodialysis therapy, linking OS to hypoalbuminemia. In this study we examined whether hypoalbuminemia in DN is also due to impaired quantification of modified albumin and assessed if modified albumin activates neutrophils to release ROS and proteases, accelerating systemic OS and inflammation. Methods: Blood samples from a cohort of 19 DN patients and 15 healthy controls were used to determine "albumin-detection index", defined as the ratio between the albumin read-out by BCG assay to the albumin concentration measured by optical density (OD) at 280 nm after albumin purification according to its size. This index was correlated with: sera albumin levels, various OS and inflammatory markers and with eGFR. Activation of separated neutrophils by glycoxidized-modified albumin was assessed by the release of neutrophil gelatinase associated lipocalin (NGAL) and myeloperoxidase (MPO). Results: The albumin-detection index of DN patients was significantly lower compared to healthy controls, correlating positively with serum albumin and kidney function, and negatively with glycoxidized albumin and inflammatory markers. Glycoxidized-albumin had a direct role in neutrophil activation, resulting in NGAL and MPO release. Conclusions: Hypoalbuminemia in DN patients, partially results from the low detection efficacy by BCG of modified/oxidized molecules, as expressed by a low albumin detection index. Modified/oxidized molecules initiate reciprocal processes by activating neutrophils, commencing a vicious cycle a of accelerated OS and inflammation. We imply that albumin detection index, a new marker of OS, may also serve as a biomarker, correlating to the severity of diabetic nephropathy.
doi:10.1016/j.freeradbiomed.2012.10.234
SFRBM 2012
revealed, that MLP mice exhibit a reduction of fractional -/shortening (FS, FVB/N wildtype vs. MLP : 24.243 ± 1.522 vs. 11.384 ± 1.096, p<0.001) and ejection fraction (EF, FVB/N -/wildtype vs. MLP : 48.448 ± 2.509 vs. 24.731 ± 2.278, p<0.001) compared to FVB/N wildtype, as expected. Remarkably, application of OA-NO2 led to a significant attenuation of the reduction of these parameters (vehicle vs. OA-NO2, FS: 11.384 ± 1.096 vs. 17.62 ± 1.101, p<0.01; EF: 24.731 ± 2.278 vs. 36.755 ± 2.003, p<0.01) resulting in an improvement of left ventricular function. Dihydroethidine staining of ventricular sections showed an attenuation of ROS production in hearts of OA-NO2 treated -/mice compared to elevated levels in vehicle treated MLP mice. Furthermore, we observed a positive effect of OA-NO2 on the contractility force and velocity using engineered heart tissue (EHT). Beyond that OA-NO2 significantly improved endothelial function (% of relaxation to 100 nM Ach treatment, FVB/N -/-/wildtype vs. MLP vs. MLP + OA-NO2, -67.22 ± 1.92 vs. -37.51 ± 3.83 vs. -53.98 ± 3.11, p<0.001) Conclusions: The current results reveal an improvement of endothelial and left ventricular function by application of OA-NO2 in a mouse model of DCM. If this effect is related to an improvement of the contractility on the single cell level or to an advancement of the vascular function still has to be determined. Nevertheless, in addition to the known anti-inflammatory properties of nitrated fatty acids, these results strongly corroborate the cardioprotective potential of nitrated fatty acids.
doi:10.1016/j.freeradbiomed.2012.10.232
177 Redox Imbalance Activates High Mobility Group Box Protein 1 Which Modulates T Cells Phenotype and Cytokine Profile in Depressed Patients. the Impact on Glucocorticoids Response. 1,2
Joanna Rybka , Kornelia Kedziora-Kornatowska1, Daria Kupczyk1, and Jozef Kedziora1 1 2 Collegium Medicum in Bydgoszcz, Poland Scienceventure Joanna Rybka, Poland Background: High- mobility group protein B1 (HMGB1) is redox sensitive inflammatory mediator acting as an effective stimulus triggering the inflammatory response. Objectives: We aimed to study HMGB1, pro- and antioxidant status alongside with T cells phenotype and Th1 and Th17 proinflammatory cytokine profiles in depressed patient. We also investigated the glucocorticoid response in relation to oxidative and inflammatory status. Methods: Blood was collected from patients diagnosed with recurrent depressive disorder (rDD) (N=15) and from healthy controls (N=19). We measured plasma hydrogen peroxide (H2O2), superoxide generation by zymosan stimulated neutrophils, reduced glutathione (GSH) and malondialdehyde (MDA) levels. Furthermore, SOD1, GPx, GR activities in red blood cells and HO1 and NOX4 levels in plasma were assessed in this study. IL2, IL-6, IL-8, IFN-γ, TNF-α, IL-17, HMGB1, neopterin and cortisol were assayed immunoenzymatically in sera. Surface phenotype expression of T regulatory and T effector cells were also investigated. The glucocorticoid response was measured by dexamethasone-induced inhibition of IL-6 produced by LPSstimulated peripheral blood. Results: We observed pro- and antioxidant imbalance in depressed patients expressed by significant changes in the enzyme activities, increased MDA, decreased GSH, increased H2O2, decreased neutrophils superoxide generation. Shifted Th1/Th17 cytokine ratios, increased Treg/Teffector cells ratio and increased levels of neopterin were also detected. Moreover, we
S78
revealed a distinct role of HMGB1 in maintaining cytokine and Treg/Teffector cells balance in depressed patients. HMGB1 remained also in relation with oxidant potential of the blood. The important role of IL-17 and inhibitory effect of MDA on glucocorticoids response was also revealed. Conclusions: Strong immunomodulatory role of HMGB1 might be related to the change of its activity caused by redox imbalance in depressed patients. The shifted immune balance alongside with prooxidative environment modulates glucocorticoid response in these patients.
doi:10.1016/j.freeradbiomed.2012.10.233
178 Is Oxidized Albumin, a Mediator and a Biomarker of Systemic Inflammation in Diabetic Nephropathy?
Regina Michelis1, Batya Kristal1,2, Galina Shapiro1, Yoav Fridman1, 1,2 Teuta Zeitun1, Ronit Geron1, and Shifra Sela 1 2 Western Galilee Hospital, Israel, Bar Ilan University, Israel Background: Hypoalbuminemia, Oxidative Stress (OS) and systemic inflammation are common in patients with diabetic nephropathy (DN). Oxidative modifications of serum albumin were shown to impair its quantification by the bromocresol-green assay (BCG) in patients on hemodialysis therapy, linking OS to hypoalbuminemia. In this study we examined whether hypoalbuminemia in DN is also due to impaired quantification of modified albumin and assessed if modified albumin activates neutrophils to release ROS and proteases, accelerating systemic OS and inflammation. Methods: Blood samples from a cohort of 19 DN patients and 15 healthy controls were used to determine "albumin-detection index", defined as the ratio between the albumin read-out by BCG assay to the albumin concentration measured by optical density (OD) at 280 nm after albumin purification according to its size. This index was correlated with: sera albumin levels, various OS and inflammatory markers and with eGFR. Activation of separated neutrophils by glycoxidized-modified albumin was assessed by the release of neutrophil gelatinase associated lipocalin (NGAL) and myeloperoxidase (MPO). Results: The albumin-detection index of DN patients was significantly lower compared to healthy controls, correlating positively with serum albumin and kidney function, and negatively with glycoxidized albumin and inflammatory markers. Glycoxidized-albumin had a direct role in neutrophil activation, resulting in NGAL and MPO release. Conclusions: Hypoalbuminemia in DN patients, partially results from the low detection efficacy by BCG of modified/oxidized molecules, as expressed by a low albumin detection index. Modified/oxidized molecules initiate reciprocal processes by activating neutrophils, commencing a vicious cycle a of accelerated OS and inflammation. We imply that albumin detection index, a new marker of OS, may also serve as a biomarker, correlating to the severity of diabetic nephropathy.
doi:10.1016/j.freeradbiomed.2012.10.234
SFRBM 2012