Increased systemic and peritoneal oxidative stress biomarkers in endometriosis are not related to retrograde menstruation.

Objetives: The goal of this study was to determine if systemic and peritoneal oxidative stress biomarkers are related to each other and to retrograde menstruation in endometriosis. Methods: Plasma and peritoneal fluid oxidative stress biomarkers and hemoglobin and erythrocytes in peritoneal fluid as retrograde menstruation indicators, were measured in 28 patients with endometriosis and 23 without endometriosis. Results: In the peritoneal fluid, carbonyls and lipohydroperoxides, indicative of protein and lipid oxidative damage, were higher in endometriosis group (21%, p = 0.016 and 46%, p = 0.009, respectively). However, these biomarkers were not different in the blood plasma of both groups, and only protein dityrosine, was increased in the plasma of endometriosis group (31%, p = 0.04). The peritoneal fluid hemoglobin content was not higher in the endometriosis group, nor related to carbonyls and lipohydroperoxides. Additionally, the peritoneal fluid oxidative biomarkers were not correlated with the blood plasma ones, and only malondialdehyde, and ischemia-modified albumin were almost two times higher in peritoneal fluid. Discussion: Our results show a peritoneal and systemic oxidative stress biomarkers increase in endometriosis, but not related to each other, and do not support the hypothesis of an increase in hemoglobin-iron supply towards the peritoneal cavity that causes oxidative damage.

Urban PM2.5 activates GAPDH and induces RBC damage in COPD patients.

During Chronic Obstructive Pulmonary Disease (COPD) progression, the intracellular antioxidant defence in RBCs must preserve the integrity of the plasmalemma through NADPH+ generation to obtain a sufficient number of reduced non-protein SH-groups. Here, we studied the activities of enzymes in RBCs that are related to glutathione metabolism under conditions of increasing oxidative stress, which are associated with COPD progression, by increasing cellular damage in vitro with PM2.5, a ROS generator. The study included 43 patients, who were separated according to their GOLD classification into moderate and severe groups, along with 11 healthy volunteers (HV). Blood samples were analysed for G6PD, GAPDH, GPx, and GR. The results showed significant decreases in the oxidation of the G6PD, GR and GPx proteins, resulting in decreased enzymatic activity. By contrast, an increase (p<0.05) in GAPDH was observed, suggesting a pool of ATP on the membrane. However, it is evident that RBCs are damaged during the progression of COPD, although their integrity is preserved, and they retain limited function, thus allowing patient survival without haemolysis.

Urban PM2.5 induces ROS generation and RBC damage in COPD patients.

Particulate matters (PM) produce adverse effects on the respiratory system and cause COPD. These effects are thought to involve intrinsic generation of ROS which are present in ambient PM (transition metals and aromatic organic compounds). Here, we examined the chemical composition and ultra-microscopic structure of PM2.5. The effect of this PM was studied in red blood cell (RBC) membranes (ghosts) from healthy volunteers (n = 11) and COPD patients (n = 43). These effects were compared with that produced by a Fenton metal-catalytic ROS generator. Oxidative biomarkers and cell damage were singificantly increased in presence of PM2.5 or ROS generator in RBC of COPD patients as compared with those in cells from healthy volunteers. In contrast, total SH groups, band 3 phospho-tyrosine phosphatase (PTPase) and glucose-6 phosphate dehydrogenase (G6PD) activities were all diminished in cells from COPD patients. In conclusion, PM2.5 increases damage to RBCs from COPD patients, decreases the activity of PTPase and G6PD, and alters the function of the anionic exchanger (AE1) and the antioxidant response by decreasing SH groups.

Correlation of Plasma Protein Carbonyls and C-Reactive Protein with GOLD Stage Progression in COPD Patients.

Oxidative stress plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). To investigate the correlation between the progression of COPD and plasma biomarkers of chronic inflammation and oxidative injury, blood samples were obtained from healthy volunteers (HV, n = 14) and stabilized COPD patients. The patients were divided into three groups according to their GOLD stage (II, n = 34; III, n = 18; IV, n = 20). C-reactive protein (CRP), protein carbonyls (PC), malondialdehyde (MDA), susceptible lipoperoxidation of plasma substrates (SLPS), and myeloperoxidase activity (MPO) were measured. The plasma concentration of SLPS was measured as the amount of MDA generated by a metal ion-catalyzed reaction in vitro. PC, SLPS, and CPR were increased significantly (p < 0.001) in COPD patients when compared to HV. MDA concentrations and MPO activities were not significantly different from those of the HV group. In conclusion, increased oxidation of lipids and proteins resulting in a progressive increase in the amount of total plasma carbonyls and oxidative stress the presence of oxidative stress during COPD progression, concomitant with an increased oxidation of lipids and proteins resulting in a progressive and significant increase in the amount of total carbonyls formed from lipid-derived aldehydes and direct amino acid side chain oxidation in plasma, may serve as a biomarker and independent monitor of COPD progression and oxidative stress injury.