Microglial iron trafficking: new player in brain injury.

BACKGROUND: Neonatal brain injury is a significant reason of neurodevelopmental abnormalities and long-term neurological impairments. Hypoxic-ischemic encephalopathy and preterm brain injury, including intraventricular hemorrhage are the most common grounds of brain injury for full-term and preterm neonates. The prevalence of hypoxic ischemic encephalopathy varies globally, ranging from 1 to 3.5/1000 live births in high-resource countries and 26/1000 in low-resource countries. Preterm birth's global incidence is 15 million, a significant reason for infant mortality and morbidity, permanent neurologic problems, and the associated social and economic burden. The widespread neurodevelopmental effects of neonatal brain injury could have an unfavorable impact on a variety of aspects of cognitive, linguistic, behavioral, sensory, and motor functions. Brain injury occurs via various mechanisms, including energy deprivation, excitatory amino acids, mitochondrial dysfunction, reactive oxygen species, and inflammation giving rise to different forms of cell death. The contribution of microglial activity in neonatal brain injury has widely been underlined by focusing on cell death mechanisms since the neuronal death pathways during their development are distinct from those in the adult brain. Iron accumulation and lipid peroxidation cause a relatively novel type of regulated cell death called ferroptosis. Neonates generally have biochemical iron inequalities, and their antioxidant potential is highly restricted, implying that ferroptosis may be significant in pathologic conditions. Moreover, inhaled nitric oxide therapy in infants may lead to microglial inflammation via ferroptosis and neuronal injury in the developing brain. This review article aims to summarize the studies that investigated the association between neonatal brain injury and iron metabolism, with a particular emphasis on the microglial activity and its application to the inhibition of neonatal brain injury.

Determination of Serum Vascular Endothelial Growth Factor Levels in Attention Deficit Hyperactivity Disorder: A Case Control Study.

OBJECTIVE: The effect of vascular endothelial growth factor (VEGF) on neuronal development is known, but its relationship with attention deficit hyperactivity disorder (ADHD), a neurodevelopmental disorder, has not yet been fully elucidated. To our knowledge, this is the first human study investigating serum VEGF levels in ADHD patients. In this study, it has been aimed to compare serum VEGF levels between a healthy control group and in ADHD patients to help determine the association between serum VEGF levels and ADHD. METHODS: This study sample included forty-four patients diagnosed with ADHD and 43 healthy volunteer controls between 7 to 14 years old. Blood samples were taken from patients and the healthy control group to assess their serum VEGF levels. VEGF levels were calculated by subjecting the optical densities of the samples to concentrations of known standards as provided in the ELISA kit and then performing a regression correlation analysis. RESULTS: The mean VEGF level of the children was 333.6 ± 209.8 in the ADHD group and 341.3 ± 201.8 in the control group. There were no statistically significant differences in serum VEGF levels between the ADHD and control groups (U = 926.000, z = -0.170, p = 0.865). CONCLUSION: There was no significant difference in serum VEGF levels for untreated ADHD cases and a healthy control group. This is the first human study investigating serum VEGF levels in ADHD patients, so there is a need to replicate these findings.

N-Methyl-D aspartate receptor-mediated effect on glucose transporter-3 levels of high glucose exposed-SH-SY5Y dopaminergic neurons.

High glucose and insulin lead to neuronal insulin resistance. Glucose transport into the neurons is achieved by regulatory induction of surface glucose transporter-3 (GLUT3) instead of the insulin. N-methyl-D aspartate (NMDA) receptor activity increases GLUT3 expression. This study explored whether an endogenous NMDA receptor antagonist, kynurenic acid (KynA) affects the neuronal cell viability at high glucose concentrations. SH-SY5Y neuroblastoma cells were exposed to 150-250 mg/dL glucose and 40 µU/mL insulin. In KynA and N-nitro-l-arginine methyl ester (L-NAME) supplemented cultures, oxidative stress, mitochondrial metabolic activity (MTT), nitric oxide as nitrite+nitrate (NOx) and GLUT3 were determined at the end of 24 and 48-h incubation periods. Viable cells were counted by trypan blue dye. High glucose-exposed SH-SY5Y cells showed two-times more GLUT3 expression at second 24-h period. While GLUT3-stimulated glucose transport and oxidative stress was increased, total mitochondrial metabolic activity was significantly reduced. Insulin supplementation to high glucose decreased NOx synthesis and GLUT3 levels, in contrast oxidative stress increased three-fold. KynA significantly reduced oxidative stress, and increased MTT by regulating NOx production and GLUT3 expression. KynA is a noteworthy compound, as an endogenous, specific NMDA receptor antagonist; it significantly reduces oxidative stress, while increasing cell viability at high glucose and insulin concentrations.

The effect of alfuzosin on renal resistive index, urinary electrolytes and ß2 microglobulin levels and TGF ß-1 levels of kidney tissue in rats with unilateral ureteropelvic junction obstruction.

BACKGROUND: In this study, it was aimed to determine the effects of alfuzosin on experimentally generated unilateral partial ureteropelvic junction obstruction (UPO) in rats. MATERIALS AND METHODS: Thirty Long-Evans rats were randomly allocated into five groups. In control group (C), nothing was performed; in group Sham (S) only laparotomy was done; in Alfuzosin group (A) only alfuzosin was administered for two weeks (10 mg/kg/day p.o.) without any surgery; in UPO group, unilateral UP junction obstruction was produced; and in the Group UPT (ureteropelvic obstruction + treatment), alfuzosin was administered for two weeks (10 mg/kg/day p.o.) in addition to UPO production. Renal pelvic anteroposterior diameters were determined with ultrasonography (USG) and renal arterial resistivity indexes by color Doppler USG. Urine was collected both at the beginning and at the end of the experiment for 24 h in all the groups and at the end of the experiment, blood samples were obtained. Blood and urine electrolytes and TGF-ß1, urine density, urine ß2 microglobulin levels were determined. Renal tissue samples harvested from all of the rats were histopathologically evaluated. Results were determined using one-way ANOVA t-test; p < 0.05 was accepted as significant. RESULTS: Urine density in the UPT group was lower with respect to UPO group and blood electrolytes were preserved as close to normal (p < 0.05). In the UPT group, urine TGF-ß1 and blood TGF-ß1, blood ß2 microglobulin levels and histopathologic damage scores were lower compared to the UPO group (p < 0.05). CONCLUSION: It is shown in this experimental unilateral partial UPO model that alfuzosin treatment prevents obstructive renal damage.

Assessment of brachial artery reactivity, carotid intima-media thickness, and adhesion molecules in pediatric solid tumor patients treated with anthracyclines.

The aim of this study was to determine subclinical atherosclerosis and endothelial functional disturbance with measurement of carotid intima-media thickness (IMT), brachial artery reactivity (BAR), and levels of serum adhesion molecules in children with solid tumors who were treated with anthracyclines and are actually in complete remission. Fifty patients who were in remission and 30 healthy children were included in the study. Mean ages of patient and control groups were 13.5 ± 4.7 years (range: 3-23 years) and 12.00 ± 4.3 years (range: 4-21 years), respectively. The patients were divided into 3 groups according to cumulative doxorubicin dose: Group 1, ≤100 mg/m(2); Group 2, 101-299 mg/m(2); Group 3, ≥300 mg/m(2). The BAR and carotid IMT were measured in order to determine the endothelial function. The serum adhesion molecule levels in our patients and controls were also measured. The BAR of the patients with cumulative anthracycline dose ≥300 mg/m(2) was significantly lower than the patients with cumulative anthracycline dose ≤100 mg/m(2) and healthy controls (P =.005 and P =.003, respectively). Also, there was a negative correlation between brachial artery reactivity and increasing cumulative anthracycline dose (r = -.287, P =.044). We also found significant difference between the mean carotid IMT of the patients and the healthy children (P =.041). No statistically significant difference was detected between the serum levels of sICAM-1 (soluble intercellular adhesion molecule-1), sVCAM-1 (soluble vascular cell adhesion molecule-1), sE-selectin of the patients and controls. The use of anthracyclines in pediatric patients with cancer could result in increase of the carotid IMT and endothelial dysfunction.

Aerobic exercise improves oxidant-antioxidant balance in patients with rheumatoid arthritis.

[Purpose] Although oxidative stress is known to be present in rheumatoid arthritis (RA), the effects of exercise on oxidative parameters are unknown. The aim of this study was to investigate the effects of acute aerobic exercise on serum oxidant and antioxidant levels in patients with RA. [Subjects and Methods] Sixteen patients with RA and 10 age-matched healthy volunteers participated in this study. All participants wore polar telemeters and walked on a treadmill for 30 minutes at a speed eliciting 60-75% of maximal heart rates. Blood samples were obtained before, immediately and 24 hours after exercise and malondialdehyde (MDA) and total sulfhydrile group (RSH) levels were measured. [Results] Both groups had similar heart rates during the test but the treadmill speed of the RA patients was significantly lower than that of the healthy volunteers. Serum MDA levels were lower than in both groups immediately after exercise, with greater decrements in the RA patients than controls. MDA levels returned to baseline 24 hours after the exercise only in the controls; they remained low in the RA patients. There was a slight increase in serum RSH levels after exercise compared to baseline in both groups. [Conclusion] Moderate intensity treadmill exercise did not have any adverse effect on the oxidant-antioxidant balance. The results suggest that such an exercise may be safely added to the rehabilitation program of RA for additional antioxidant effects. Morever, this antioxidant environment is maintained longer in RA patients.

Oxidized low-density lipoprotein levels and carotid intima-media thickness as markers of early atherosclerosis in prepubertal obese children.

OBJECTIVES: Children with obesity have a high cardiovascular risk and an impaired oxidant-antioxidant status, which may lead to endothelial dysfunction and increased carotid intima media thickness (IMT) even in childhood. The aim of this study was to investigate the circulating oxidized low-density lipoprotein (LDL) concentrations and the IMT of carotid arteries in prepubertal obese children, and also to search for its possible association with carotid atherosclerosis. METHODS: Twenty-seven prepubertal obese children (age, 7.48±2.05 years; boys, 59%) and 30 healthy children (age, 7.80±2.19 years; boys, 55%) were included in the study. Serum concentrations of oxidized LDL, total cholesterol, triglyceride, high-density lipoprotein, LDL, and glucose were measured, and carotid IMT was determined by ultrasound. RESULTS: Serum oxidized LDL levels were significantly higher in prepubertal obese children than in healthy children (p<0.01). No significant correlation was observed between oxidized LDL levels and carotid IMT measurements. However, a significant positive correlation was found between oxidized LDL levels and body mass index, total cholesterol, and LDL-cholesterol. CONCLUSION: Our findings revealed that the oxidation of LDL starts early in obese children but the carotid IMT is not significantly affected. Also, oxidized LDL levels are more strongly associated with obesity and dyslipidemia than the carotid IMT in prepubertal children.

Matrix metalloproteinase-7 and matrix metalloproteinase-9 in pediatric multiple sclerosis.

Matrix metalloproteinases and their tissue inhibitors play a key role in the pathogenesis of adult-onset multiple sclerosis, and were suggested as biomarkers of response to interferon-ß, an established treatment in multiple sclerosis. However, data regarding pediatric population are scarce. We determined serum levels of matrix metalloproteinase-7, matrix metalloproteinase-9, and tissue inhibitor of matrix metalloproteinase-1 in children, and evaluated effects of interferon-ß therapy on these measures. Serum samples from 14 children with relapsing, remitting multiple sclerosis at baseline and at month 12, and from 15 controls, were collected. Interferon-ß treatment was initiated in eight patients. Mean serum matrix metalloproteinase-9 levels and matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 ratio were higher in patients compared with controls, and were reduced significantly in treated patients at month 12, but did not change in untreated patients. Mean matrix metalloproteinase-7 levels were lower in patients compared with controls, and increased significantly in the treated group, but did not change significantly in the untreated group. In pediatric multiple sclerosis, a shift in matrix metalloproteinase-9/tissue inhibitor of matrix metalloproteinase-1 balance toward proteolytic activity is evident, and interferon-ß therapy demonstrates a beneficial effect on this disturbed balance.

Is neopterin a diagnostic marker of acute appendicitis?

BACKGROUND: The diagnosis of acute appendicitis, even for experienced surgeons, can sometimes be complex. A delay in diagnosis increases the complication rate. This experimental study aimed to investigate the suitability and significance of neopterin as a marker for acute appendicitis. METHODS: The levels of neopterin were measured using an acute appendicitis animal model in 35 New Zealand male rabbits. They were divided into 5 groups as Group 1= control; Group 2= sham; and Groups 3 (12-hour); 4 (24-hour); and 5 (48-hour) (based on the elapsed time period before their appendectomies). The neopterin levels of each group were measured by neopterin enzyme immunoassay kit in blood samples (taken before the appendectomies in Groups 3, 4 and 5). RESULTS: For the diagnosis of acute appendicitis, the optimal cut-off point was 34.475 nmol/L. The probability of acute appendicitis was found to be 4.667 times higher when the neopterin level was greater than 34.475 nmol/L. CONCLUSION: This study was an experimental animal study; however, it provides valuable clues useful in clinical assessment. Neopterin seems to have great potential as a new diagnostic marker for the diagnosis of acute appendicitis.

Prevalence of selective immunoglobulin A deficiency in healthy Turkish school children.

Immunoglobulin A (IgA) deficiency is the most common primary deficiency. We aimed to define the prevalence of IgA deficiency among healthy school children in Turkey and the differences between geographical regions. Blood samples were collected from 20,331 healthy school children from all regions across Turkey. The serum IgA levels were tested through nephelometric method, and all 108 samples with IgA levels lower than 5 g/L were tested through ELISA for IgG and IgM levels. All IgG and IgM values were within the normal range in all cases, and no concomitant deficiency was observed. Our study results showed that the selective IgA deficiency incidence was 0.52% (1:188). The highest incidence, of 1:128.7, was observed in children from the Marmara region; the Black Sea Region levels (1:132.7) were lower, and the Mediterranean levels (1:365.7) were the lowest.

Increased serum levels of epidermal growth factor in children with autism.

The etiology of autism is unclear, however autism is considered as a multifactorial disorder that is influenced by neurological, environmental, immunological and genetic factors. Growth factors, including epidermal growth factor (EGF), play an important role in the cellular proliferation and the differentiation of the central and peripheral nervous system. In this study we hypothesized that EGF may play a role in the pathophysiology of autism and examined serum EGF levels in children with autism. We measured serum levels of EGF in the 27 autistic children and 28 age- matched normal controls. The serum levels of EGF in the subjects with autism were significantly higher than those of normal control subjects. However, there were no correlations between serum EGF levels and clinical variables in the subjects with autism. This is the first report demonstrating the increased serum levels of EGF in children with autism. This study suggests that increased levels of EGF might have an importance in the pathophysiology of autism.

Anti-infliximab antibody status and its relation to clinical response in psoriatic patients: A pilot study.

Although the mechanisms underlying the loss of response to infliximab are not completely understood, the formation of antibodies to infliximab (ATI) are thought to play a role. The aim of this study was to investigate the presence of ATI in psoriatic patients and to evaluate its relationship to the clinical response. Fifteen patients with psoriasis were treated with infliximab (5 mg/kg) every 8 weeks after an initial three-dose induction treatment. An enzyme linked immunosorbent assay kit was used for analyzing the presence of ATI in sera. Effectiveness assessments included the change in Psoriasis Area and Severity Index (PASI) compared with study entry. Five (33.3%) patients developed ATI. While 5.9 +/- 3.2 infliximab infusions achieved a fall in the PASI score from a mean of 20.4 +/- 8.3 to 5.3 +/- 2.4 in ATI-negative patients, these values changed from 23.3 +/- 11 to 10 +/- 4.9 after 9 +/- 5.2 infusions in ATI-positive patients. Our results suggested that ATI measured in psoriatic patients are of clinical importance. Therefore, monitoring for the induction of ATI and rescue strategies should be developed to avoid or to maintain a delay in ATI development.

The relationship between adiponectin levels and proinflammatory cytokines and left ventricular mass in dialysis patients.

INTRODUCTION: Adiponectin is increased in end-stage renal disease. However, efforts to clarify the cause of that increase and its clinical effects have been inconclusive. The aim of this study was to compare serum adiponectin levels of dialysis patients against healthy individuals and evaluate the relationship among adiponectin levels, IL-6, TNF- alpha and left ventricular mass index (LVMI). METHODS: Adiponectin, IL-6 and TNF- alpha measurements and echocardiographic evaluations were performed in 36 hemodialysis, 30 continuous ambulatory peritoneal dialysis (CAPD) patients and 22 healthy volunteers. Adiponectin, IL-6 and TNF- alpha levels were measured by ELISA. RESULTS: Adiponectin was found to be higher in hemodialysis (52.78+/-18.01 ng/mL) and CAPD (52.96+/-17.53 ng/mL) groups than controls (28.36+/-13.20 ng/ mL; p=0.0003, p=0.0003, respectively). No difference was observed between the hemodialysis and CAPD groups. Adiponectin was positively correlated with IL-6 (r=0.293, p=0.02), TNF- alpha (r=0.458, p=0.0003) and LVMI (r=0.283, p=0.02). In the partial correlation analysis, by controlling for body mass index, the correlation between adiponectin and TNF- alpha (r=0.466, p=0.0003) persisted. When IL-6 was controlled with TNF- alpha, the relation between adiponectin and LVMI disappeared (r=0.145, p=0.30). In the linear regression analysis, with adiponectin as the dependent variable, and IL-6, TNF- alpha and body mass index as independent variables, a significant relationship was found between adiponectin and TNF- alpha (beta=0.488, p=0.001). CONCLUSIONS: Increased adiponectin seems to be associated with increased proinflammatory cytokines in dialysis patients, and this relationship suggests adiponectin may have a role in the development of left ventricular hypertrophy.

Salivary epidermal growth factor levels in Behçet's disease and recurrent aphthous stomatitis.

BACKGROUND: Epidermal growth factor (EGF) in saliva is cytoprotective against injuries and contributes to the maintenance of the integrity of the gastrointestinal mucosa. Low salivary EGF levels have been observed in patients with various forms of oral mucosal disease. OBJECTIVE: Our aim was to determine whether salivary EGF is low in patients with recurrent aphthous stomatitis (RAS) or those with Behçet's disease (BD) when compared with healthy controls. METHODS: The study population consisted of 33 BD and 16 RAS patients and 60 healthy controls. Measurement of EGF concentration in human saliva was performed with an enzyme-linked immunosorbent assay using an antibody-coated solid phase. RESULTS: The mean salivary EGF levels (+/-SD) of active (with oral ulceration) and inactive stages (absence of oral ulceration) of BD (1,939.7 +/- 1,561.5 and 2,305.7 +/- 1,481.6 pg/ml, respectively) and RAS patients (1,650.5 +/- 704.7 and 1,069.9 +/- 539.2 pg/ml, respectively) were both lower than those of the healthy controls (2,758.7 +/- 1,657.9 pg/ml) (p < 0.05 for each). CONCLUSIONS: BD and RAS patients have reduced salivary EGF levels even in the absence of oral ulcerations. EGF could be involved in the pathogenesis of BD and RAS by disturbing the mucosal integrity that may result in a susceptibility to the development of oral ulcers in these diseases.

Determinants of protection against diphtheria in adult hemodialysis patients.

Diphtheria is of great epidemiological concern. Although mainly observed during childhood, unvaccinated adults and relatively immunocompromised patients are at increased risk for acquiring diphtheria. We aimed to determine the rates and certain determinants of protection against diphtheria in adult hemodialysis (HD) patients. Protection rates of 322 HD patients were compared with 65 diabetes mellitus type 2 (DM) patients and 65 healthy controls. A questionnaire was held in regard to smoking habits and alcohol intake. Antibody levels against diphtheria were assessed by an in-house ELISA and a concentration of >or=0.1 IU/mL was regarded as protective. Effects of age, gender and time being on dialysis on protection were assessed by logistic regression. Ratios of individuals with protective antibody levels were found to be 36% (116/322), 27.7% (18/65), and 52.3% (34/65) for HD, DM, and control groups, respectively. Hemodialysis patients had a significantly (p < 0.05) lower protection rate than healthy controls. In all study groups, there was a tendency of higher protection rate with increasing age. These low ratios of protected individuals in both HD and DM patient groups are alarming, as these patients generally have defects in vaccine responses, and carriage is important in the perpetuation of diphtheria. The protection status of these patient groups might be improved with additional vaccinations.

Investigation of the functional characteristics of antibodies to therapeutic anti-human tumor necrosis factor alpha monoclonal antibody.

Humanized antibody-based treatment modalities represent an active area of investigation. Included in these strategies are passive administrations of monoclonal antibodies, which recognize tumor necrosis factor alpha (TNF-alpha). However, several problems associated with these types of treatment strategies have been reported in the literature. We attempted to address the issue related to unresponsiveness to infliximab that might be induced by anti-idiotype response to the passively administered humanized monoclonal antibody. The characteristics and functional importance of antibodies to infliximab (ATI) were investigated in human sera. We studied the binding characteristics of ATI to infliximab, TNF-alpha Receptor-I (RI, p55) and Receptor-II (RII, p75). In addition, cytotoxicity effect on L929 cells and blocking effects on the binding of TNF-alpha with infliximab and etanercept were also analyzed. On the basis of the results obtained from the experiments, it seems that the target epitope for ATI is related with somewhere else not residing in the region capable of generating "mirror image". The results presented indicate that ATI does not mimic the functional characteristics of TNF-alpha. However, ATI inhibited the binding properties of infliximab to TNF-alpha.