Ghada Abdel-Hamid Daoud

Total hydroperoxide and biological antioxidant potentials in a neonatal sepsis model.

Oxidant/antioxidant imbalance plays an important role in septic shock. The present study examined changes in circulating oxidative components in a neonatal sepsis model. Subjects were 14 newborn mixed-strain piglets randomly divided into two groups: a cecal ligation and perforation (CLP) model (n = 7) and sham (n = 7). Blood samples for total hydroperoxide (TH), biological antioxidant potential (BAP), tumor necrosis factor (TNF) α, interleukin (IL)-6, and IL-10 were collected pre-CLP and at 1, 3, and 6 h post-CLP. TH and BAP levels at 1 h post-CLP were significantly higher in the CLP group than in the sham group. In the CLP group, TH decreased gradually and reached baseline levels by 6 h post-CLP, while BAP remained elevated. Linear correlations were identified between serum TH and BAP at 1 h post-CLP, serum TH and TNF-α at 1 h post-CLP, and BAP and IL-6 at 6 h post-CLP. Changes in and correlations between circulating oxidative and inflammatory state components in a neonatal sepsis model were clarified. This is the first study to reveal that the presence of oxidant/antioxidant imbalance in sepsis and septic shock changes during the disease course.

Edaravone, a novel free radical scavenger, reduces high-mobility group box 1 and prolongs survival in a neonatal sepsis model.

Free radicals play an important role in the inflammatory process of sepsis. We hypothesized that edaravone, a novel free radical scavenger, can suppress pathophysiological events and prolong survival in a neonatal sepsis cecal ligation and perforation (CLP) model. Of 32 3-day-old anesthetized and mechanically ventilated piglets, 11 received CLP only, 10 received CLP and edaravone treatment starting 30 min after CLP, and 11 constituted a sham (control) group. Mean arterial pressure (MAP), heart rate, cardiac output, arterial blood gas, serum total hydroperoxide, nitrite and nitrate, TNF-&agr;, and high-mobility group box 1 (HMGB1) were measured before CLP and at 1, 3, and 6 h after CLP. Compared with the CLP group, the edaravone group showed higher MAP at 6 h, lower heart rate at 1 and 3 h, lower total hydroperoxide at 1 h, lower nitrite and nitrate at 3 and 6 h, and higher (although not significantly so) mean cardiac output at 1, 3, and 6 h. TNF-&agr; elevation was delayed from 1 h in the CLP group to 3 h in the edaravone group. In the edaravone group, HMGB1 did not change significantly at any time, whereas in the CLP group, it increased at 6 h. Survival times were longer in the edaravone group than in the CLP group (15.4 ± 1.4 vs. 10.2 ± 1 h; P < 0.005). In addition, each of the serial dilutions of edaravone had a higher biological antioxidant potential than tempol does. In conclusion, edaravone suppressed free radicals, delayed the TNF-&agr; surge, and prevented HMGB1 elevation, thereby maintaining MAP and prolonging survival time in a neonatal sepsis CLP model.

Effect of hemoperfusion using polymyxin B-immobilized fiber on IL-6, HMGB-1, and IFN gamma in a neonatal sepsis model.

To evaluate effects of polymyxin B direct hemoperfusion (PMX-DHP) on a neonatal sepsis cecal ligation and perforation (CLP) model, in 24 anesthetized and mechanically ventilated 3-d-old piglets, 16 were assigned to CLP and an arteriovenous extracorporeal circuit from 3 h until 6 h post-CLP, with a PMX-column in PMX-DHP–treated group (8 piglets) and 8 as sham. Plasma lipopolysaccharide (LPS) was measured at before CLP and at 3 and 9 h. Changes in mean systemic blood pressure (mSBP), mean pulmonary blood pressure, serum IL-6, tumor necrosis factor alpha, interferon gamma, and highly mobile group-1 box protein were measured before CLP and at 1, 3, 6, and 9 h. LPS was lower in the sham and PMX-DHP groups than in the control at 9 h. The mSBP was higher in the sham and PMX-DHP groups than in the control at both 6 h. IL-6 was lower in the sham and PMX-DHP groups than in the control at 6 h. HMGB-1 was lower in the PMX-DHP group than in the control at 6 h. IFN-γ was only detected in the control group at 9 h. Survival times in the PMX-DHP group were longer than in the control. Thus, PMX-DHP improved septic shock in a neonatal septic model.

High cerebrospinal fluid antioxidants and interleukin 8 are protective of hypoxic brain damage in newborns

Abstract The objective was to explain the discrepancy in the development of hypoxic ischemic brain injury (HIE) in some asphyxiated newborns rather than others. Forty newborns were classified according to their cerebrospinal neuron-specific-enolase (CSF-NSE) levels on their 5th-day of life; group 1 with low-NSE (n = 25). The remaining 15 newborns had high-NSE and were further divided into a group with no HIE (n = 10, group 2) and another with HIE (n = 5, group 3). CSF-NSE, totalhydroperoxide (TH), biological-antioxidant-potentials (BAPs), 12 cytokines and Erythropoietin (EPO) were measured. The TH/BAP gave the oxidative-stress-index (OSI). The BAPs of serial dilutions of three types of EPO were tested. CSF-NSE and TH and mean OSIs were higher in group 3. IL-8 and mean BAPs were higher in group 2 than in group 1. EPO was less detected in group 3. Serial EPO dilutions correlated with their BAPs. Compensatory antioxidants and IL-8 elevation could be protective of perinatal asphyxic brain injury. Antioxidative effect of EPO could be neuroprotective.

The sex differences of cerebrospinal fluid levels of interleukin 8 and antioxidants in asphyxiated newborns.

Newborn males are more sensitive to brain injury than newborn females are. The aim of the present study was to find an explanation for this. We used the neuron-specific enolase (NSE) levels in the cerebrospinal fluid (CSF) for the classification of 32 newborns (19 males and 13 females) on their fifth postnatal day. The NSE levels were higher than normal (8.4 ± 1.6 ng/mL) in 10 newborn males and 6 females and were, respectively, considered asphyxiated male and female groups. The remaining newborns, 9 males and 7 females, had normal CSF levels of NSE and were considered normal newborn male and female groups. The CSF samples were measured for 12 cytokines, using a cytokine array kit, and for total hydroperoxide and biological antioxidant potentials (BAPs), using the free radical analytic system. Among the 12 cytokines measured, only interleukin 8 (IL-8) was properly detected. The CSF levels of IL-8 were higher in the asphyxiated newborn females than in the other three groups. The mean CSF levels of BAPs in the asphyxiated newborn females were higher compared with the other three groups, but significance was detected only in comparison with the BAP levels in the CSF samples of the normal newborn males. There were no differences in total hydroperoxide levels among the groups. There are sex-related differences in the CSF levels of IL-8 and antioxidants in asphyxiated newborns, with higher levels in newborn females; this might contribute in the sexual dimorphism regarding the fact that females have better protection from brain injury than the males.

Children undergoing liver transplantation for treatment of inherited metabolic diseases are prone to higher oxidative stress, complement activity and transforming growth factor-β1.

BACKGROUND Main indications for liver transplantation in the pediatric population include biliary atresia and inherited metabolic diseases. The present study evaluated whether there are differences between pediatric patients undergoing living-related liver transplantation due to the two diseases in terms of their oxidative and immunological status during their regular outpatient follow-up visits. MATERIAL AND METHODS A clinical outpatient study measuring serum oxidative stress index (calculated as serum oxidant/antioxidant ratio, in the form of serum total hydroperoxide/serum biological antioxidative potential), serum terminal complement component 5a, as an indicator of complement activity and immunological status, and transforming growth factor-ß1, as a marker of liver fibrosis, in 16 patients (6 males and 10 females, 2.5-15 years old) who received living-related liver transplantation due to inherited metabolic diseases (n=6; in the form of propionic acidemia [n=1], methylmalonic acidemia [n=1], arginase deficiency [n=1], tyrosinemia [n=2], and glycogen storage disease type 1b [n=1], with an age range of 2.4-14.6 years old) and due to biliary atresia ([n=10], with an age range of 2.9-14.5 years old). RESULTS Serum oxidative stress index, complement component-5a, and transforming growth factor-ß1 were significantly higher in the inherited metabolic diseases group than in the biliary atresia group. In all patients, serum oxidative stress index correlated positively with complement component-5a and transforming growth factor-ß1. CONCLUSIONS Patients who receive living-related liver transplantation due to inherited metabolic diseases are prone to higher oxidative stress, complement activity, and serum transforming growth factor-ß1.

Late circulatory dysfunction and decreased cerebral blood flow volume in infants with periventricular leukomalacia.

Periventricular leukomalacia is a major neuropathology in preterm infants associated with adverse motor and cognitive outcome. The cerebral blood flow volume of the internal carotid artery and the vertebral artery was measured by ultrasonography at the neck in 36 low-birth-weight infants with gestational age of 25-34 weeks in order to investigate the pathophysiology of cerebral white-matter injury: 30 infants, normal and 6 infants, diagnosed as PVL. The mean blood flow velocity and diameter of each vessel were measured at postnatal days from day 0 to day 70. The intravascular flow volume was determined by calculating the mean blood flow velocity and the cross-sectional area. The mean blood pressures were recorded and PaCO(2) was determined. The total blood flow volume was significantly lower in infants with PVL than in normal infants on days 0, 1, 21, 28, 35, 42, and 63. The mean blood pressure was significantly lower in infants with PVL than in normal infants on days 7, 14, 21, 28, and 42. We suggest that the total cerebral blood supply is decreased in cases of PVL in the few days after birth and from day 21 to day 42. The results of the present study suggest that a dip in the blood flow volume in the few days after birth might result in subsequent PVL.

Reduced nitric oxide in amniotic fluid of patients with chorioamnionitis.

Objective: Levels of nitric oxide (NO) and cytokines were assessed in amniotic fluid obtained from patients with severe chorioamnionitis (CAM) and appropriate controls. Methods: Amniotic fluid was obtained from 12 patients with CAM (17–24 weeks of gestation) and 89 patients undergoing diagnostic amniocentesis (16–18 weeks of gestation). The concentrations of NO, interleukin-6 (IL-6), and leukocyte elastase (LE) in amniotic fluid were then measured and compared. Results: The concentrations of NO, IL-6, and LE were all higher in CAM cases than in normal pregnant women. Furthermore, an inverse correlation between NO and LE was suggested in the CAM group. Conclusions: These results indicate that in severe CAM, the action of NO might be reduced, not only due to blockage of action but also by degradation, despite increased production.

Endothelin receptor antagonist attenuates oxidative stress in a neonatal sepsis piglet model

Background:Oxidative stress (oxidant–antioxidant imbalance) plays an important role in the pathophysiology of neonatal sepsis. This study evaluated whether an antisense peptide endothelin receptor antagonist, ETR-P1/fl, could attenuate oxidative stress in a neonatal sepsis model.Methods:A total of 18 3-d-old piglets were anesthetized and mechanically ventilated. Six piglets received cecal ligation and perforation (CLP group) for induction of sepsis. Six piglets also received continuous infusion (0.05 mg/kg/h) of ETR-P1/fl 30 min after CLP (ETR-P1/fl group). Six piglets received a sham operation. Serum total hydroperoxide (TH), biological antioxidant potentials (BAPs), oxidative stress index (OSI, calculated as TH/BAP), interleukin (IL)-6, serum glutamic oxaloacetic transaminase (GOT), and creatinine were measured before CLP and at 1, 3, and 6 h after CLP.Results:CLP evoked a state of shock resulting in elevated TH, OSI, and IL-6 levels. ETR-P1/fl administration after CLP resulted in lower serum TH at 1 and 3 h after CLP, OSI at 1 and 3 h after CLP, IL-6 at 1 and 3 h after CLP, and GOT at 3 and 6 h after CLP as compared with the CLP group.Conclusion:ETR-P1/fl treatment significantly attenuated the elevation of serum oxidative stress markers (TH and OSI), IL-6, and GOT in a progressive neonatal sepsis CLP model.

Hypothermia attenuates the severity of oxidative stress development in asphyxiated newborns

PURPOSE This retrospective case-control study aimed to examine the development of oxidative stress in asphyxiated infants delivered at more than 37 weeks of gestation. MATERIAL AND METHODS Thirty-seven neonates were stratified into 3 groups: the first group experienced hypothermia (n = 6); the second received hypothermia cooling cup treatment for 3 days, normothermia (n = 16); and the third was the control group (n = 15). Serum total hydroperoxide (TH), biological antioxidant potential, and oxidative stress index (OSI) (calculated as TH/biological antioxidant potential) were measured within 3 hours after birth. RESULTS Serum TH and OSI levels gradually increased after birth in hypothermia and normothermia cases. At all time points, serum TH and OSI levels were higher in hypothermia and normothermia cases than in control cases. Serum TH and OSI levels were higher in normothermia cases than in hypothermia cases at days 3, 5, and 7. CONCLUSION This study demonstrated that hypothermia attenuated the development of systemic oxidative stress in asphyxiated newborns.