The effects of omega-3 fatty acids on the newborn rat hyperoxic lung injury.

Objective: Bronchopulmonary dysplasia (BPD) is an important cause of morbidity in preterms. Inflammation plays a central role in the pathogenesis of the disease while omega-3 fatty acids are known to have anti-inflammatory effects. In this study, we examined the effects of supplementary omega-3 fatty acids on hyperoxic lung injury.Methods: Experimental hyperoxic lung injury induced newborn 3-day-old rats were monitored in a confined hyperoxic environment with an oxygen concentration of 90-95% for a 2-week period. Rats were divided into three groups as placebo, low-dose Omega-3, and high-dose Omega-3. During the 2-week study period, low and high-dose Omega-3 groups were given 300 and 600 mg/kg/day omega-3 docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) respectively, while those in placebo received the same amount of serum physiologic. At the end of the 2-week study, lungs of all the rats were removed and morphologic evaluation under light microscopy was performed. Mean cord length (Lm), alveolar surface area (SA), and alveolar wall thickness (Wt) were calculated to find out whether a statistically significant difference between groups existed.Results: Similar alveolar development was observed between groups. No difference was seen between mean Lm values. Although the alveolar surface area was found to be higher in high-dose omega-3 group, the difference was not considered to be statistically significant. While the widest alveolar wall thickness was observed in the placebo group, alveolar wall thickness difference between high-dose omega-3 group and placebo group was found to be statistically significant (placebo Wt=17,8 ± 2.3 µm, low-dose omega -3 Wt=15,6 ± 2,5 µm, high-dose omega -3 Wt=14,2 ± 2 µm) (p < .05).Conclusions: Omega-3 fatty acids were observed to prevent alveolar wall thickness to some extent, though with no noticeable effect on hyperoxic lung injury.

Urinary Netrin-1: A New Biomarker for the Early Diagnosis of Renal Damage in Obese Children.

OBJECTIVE: Urinary netrin-1 is a new marker to demonstrate early tubular damage. The aim of this study was to determine whether urinary netrin-1 is increased in obese children. METHODS: A total of 68 normoalbuminuric and normotensive obese patients and 65 controls were included in the study. Urine samples were collected for assessment of urinary phosphorus, sodium, potassium, creatinine, albumin, and netrin-1. Blood samples were collected for measurements of fasting glucose, insulin, lipid, phosphorus, sodium, potassium, and creatinine levels. Homeostatic model assessment insulin resistance index was calculated. RESULTS: Gender and age were similar between obese and control groups (12.01±3.03 vs. 11.7±3.2 years, p=0.568 and 33 vs. 35 girls, p=0.543, respectively). Obese patients had significantly higher netrin-1 excretion than the controls (841.68±673.17 vs. 228.94±137.25 pg/mg creatinine, p=0.000). Urinary netrin-1 level was significantly higher in obese subjects with insulin resistance compared to those without insulin resistance (1142±1181 vs. 604.9±589.91 pg/mg creatinine, p=0.001). CONCLUSION: In normotensive and normoalbuminuric obese children, urinary netrin-1 level can increase before onset of albuminuria. Urinary netrin-1 excretion appears to be affected predominantly by insulin resistance and hyperinsulinemia. Urinary netrin-1 may be a new biomarker for determining early tubular injury in obese children.

Treatment with oestrogen-receptor agonists or oxytocin in conjunction with exercise protects against myocardial infarction in ovariectomized rats.

NEW FINDINGS: What is the central question of this study? Could the activation of oxytocin or oestrogen receptors be protective against myocardial injury after ovariectomy? If so, would exercising have an additional ameliorating effect? What is the main finding and its importance? The results revealed that when accompanied by exercise, both oestrogen receptor agonists and oxytocin improved cardiac dysfunction, inhibited the generation of pro-inflammatory cytokines and reduced myocardial injury in ovariectomized female rats, suggesting a new approach for protecting postmenopausal women against ischaemia-induced myocardial injury. To investigate the putative protective effects of oxytocin or oestrogen receptor agonists against myocardial injury of ovariectomized sedentary or exercised rats, female Sprague-Dawley rats assigned to sham-operated control and ovariectomized (OVX) groups were kept sedentary or undertook swimming exercise for 4 weeks and were treated with saline, an oestrogen receptor (ER) ß (DPN) or ERα agonist (PPT) or oxytocin. Ovariectomy increased weight gain and anxiety in sedentary rats, whereas exercise prevented weight gain. When accompanied by exercise, both ER agonists and oxytocin inhibited weight gain and anxiety; oxytocin, in the absence or presence of exercise, increased the left ventricular diastolic dimensions and ejection fraction, whereas ER agonists also increased left ventricular diameter when given to exercised rats. Upon the induction of myocardial ischaemia-reperfusion in the OVX rats, plasma creatine kinase-(muscle-brain) was depressed by PPT and oxytocin, whereas DPN, PPT and OT reduced plasminogen activator inhibitor-1 concentrations. The increased tumour necrosis factor-α concentration in OVX rats was also suppressed by exercise or DPN, PPT or oxytocin treatments, whereas the interleukin-6 concentration was diminished by all the treatments when given in conjunction with exercise. Disorganization of cardiac muscle fibres was reduced in all exercised rats. Oestrogen receptor agonists, as well as oxytocin, in conjunction with exercise may be effective new therapeutics to protect against myocardial ischaemia in postmenopausal women.

High serum 25-hydroxyvitamin D levels are associated with pediatric sepsis.

Despite major advances in intensive care, sepsis continues to be a major cause of morbidity and mortality. Vitamin D is involved in various physiologic functions, including cellular responses during infection and inflammation. The aim of this study was to evaluate diagnostic value of 25-hydroxyvitamin D in childhood sepsis because it can be fatal if diagnosis delayed. The study included 40 children with sepsis and 20 children without sepsis (control group). We included only the patients with high probable sepsis, judged by clinical and laboratory findings, including positive blood culture. Blood samples were collected from patients with sepsis before treatment (pre-treatment group) and 48-72 hours later (post-treatment group). Treatment varied from ampicillin-sulbactam to cephalosporin. Blood samples were collected from control group once on admission. Serum 25-hydroxyvitamin D levels were significantly higher in sepsis (pre-treatment group) than control group (74 ± 8 ng/ml vs. 28 ± 12 ng/ml, p = 0.01) and the serum 25-hydroxyvitamin D levels were decreased to 44 ± 5 ng/ml (p = 0.01) after treatment. Moreover, we found significant positive correlation between 25-hydroxyvitamin D and each of well-know sepsis markers, C-reactive protein, tumor necrosis factor-α and interleukin-6. A cut-off point of 20 ng/mL for serum 25-hydroxyvitamin D showed 84% sensitivity and 76% specificity for sepsis diagnosis. This is the first study evaluating the diagnostic role of vitamin D in pediatric sepsis, thereby suggesting that serum 25-hydroxyvitamin D level can be used as a diagnostic marker for sepsis with high sensitivity and specificity.

Protective effects of melatonin therapy in model for neonatal hyperoxic lung injury.

CONTEXT: Bronchopulmonary dysplasia (BPD) is a common outcome of premature birth. Currently, no effective preventive therapy is available for BPD, but the major role of O2 toxicity in the development of BPD has gained attention, particularly for developing new antioxidants for prevention. The major protective mechanism of melatonin (MT) includes free-radical scavenging activity and activation of the cyclooxygenase-prostoglandin enzyme system. OBJECTIVE: The aim of this study was to evaluate the effects of MT on cytoprotection and healing in a model of hyperoxic lung injury in newborn rats. METHODS: This is a case-control study design. SETTING: The study occurred at the Gulhane Military Medical Academy in Ankara, Turkey. INTERVENTION: A total of 60 newborn pups from dated, Sprague-Dawley, pregnant rats were divided equally into 3 groups as follows: (1) control group, (2) hyperoxia-exposed group, and (3) hyperoxia-exposed plus MT-treated group (MT group). Hyperoxia was performed by placing these pups in an oxygen chamber for 14 d during which oxygen was continuously delivered. OUTCOME MEASURES: At the end of the 14 d, lung specimens were collected and evaluation of the lamellar-body count and determination of histopathological scores were performed. Also, the activities of superoxide dysmutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were assessed. RESULTS: The histopathological scores of the MT group were significantly lower than those of the hyperoxia-exposed group. The mean lamellar-protein and radial-alveolar counts in the MT group were found to be significantly higher than those of the hyperoxia-exposed group. Also, SOD and GSH-Px levels were significantly higher and MDA levels were significantly lower in the MT group compared with the hyperoxia-exposed group. CONCLUSION: MT therapy was found to have a protective effect in a model for hyperoxic lung injury in neonatal rats. Therefore, the research team suggests that MT therapy may be used for prevention of BPD in preterm infants after confirmation of this data by future clinical studies.

Captopril protects against burn-induced cardiopulmonary injury in rats.

BACKGROUND: This study was designed to determine the possible protective effect of captopril treatment against oxidative damage in heart and lung tissues induced by burn injury. METHODS: Under ether anesthesia, the shaved dorsum of Wistar albino rats was exposed to 90°C water bath for 10 seconds. Captopril was administered intraperitoneally (10 mg/kg) after the burn injury and repeated twice daily. In the sham group, the dorsum was dipped in a 25°C water bath for 10 seconds. At the end of the 24 hours, echocardiographic recordings were performed, then animals were decapitated and heart and lung tissue samples were taken for the determination of tumor necrosis factor-α (TNF-α) as a pro-inflammatory cytokine, malondialdehyde and glutathione levels and myeloperoxidase, caspase-3, and Na+,K+-ATPase activity in addition to the histological analysis. RESULTS: Burn injury caused significant alterations in left ventricular function. In heart and lung tissues, TNF-α and malondialdehyde levels and myeloperoxidase and caspase-3 activities were found to be increased, while glutathione levels and Na+, K+-ATPase activity were decreased due to burn injury. Captopril treatment significantly elevated the reduced glutathione level and Na+, K+-ATPase activity, and decreased cytokine and malondialdehyde levels and myeloperoxidase and caspase-3 activities. CONCLUSION: Captopril prevents burn-induced damage in heart and lung tissues and protects against oxidative organ damage.

Comparing beneficial effects of inhaled nitric oxide to L-arginine in necrotizing enterocolitis model in neonatal rats.

OBJECTIVE: Necrotizing enterocolitis (NEC) is a common and devastating gastrointestinal condition of neonatal infants. The pathophysiology of NEC remains poorly understood. We tried to evaluate the effectiveness of inhaled NO compared to L-arginine usage in necrotizing enterocolitis model in rats. MATERIAL-METHODS: 46 newborn pups from 4 time-mated Sprague-Dawley pregnant rats were divided equally into 4 groups as follows: NEC (subjected to NEC), NEC + L-arginine, NEC + inhaled NO and control. RESULTS: SOD, GSH-Px and NOx levels were significantly higher and MDA levels were significantly lower in NEC + inhaled NO group compared to NEC + L-arginine group. There was significantly lower intestinal injury and apoptosis index scoring in NEC + inhaled NO group compared to NEC + L-arginine group. CONCLUSION: We think that inhaled NO can be used as a novel therapeutic agent like L-arginine in NEC, like using in pulmonary hypertention in newborns but much more studies are needed.

Bilateral renal hypoplasia and cystic dysplasia: a new phenotype of Thomas syndrome or a new syndrome?

Thomas syndrome is a rare syndrome including Potter sequence, renal anomalies, heart defects, cleft palate with other oropharyngeal anomalies. Here, we report a newborn with Potter sequence, bilateral renal hypoplasia and cystic dysplasia, multiple cardiovascular malformations, long large ears, frontal bossing, small lips, partial simple toe syndactyly, and cleft palate. To our best knowledge, this patient may be considered as a new variant of Thomas syndrome or a new syndrome.

Resveratrol improves cardiovascular function and reduces oxidative organ damage in the renal, cardiovascular and cerebral tissues of two-kidney, one-clip hypertensive rats.

OBJECTIVES: The putative protective effects of resveratrol against oxidative injury in the heart, kidney and brain tissues of rats induced with the two-kidney, one-clip (2K1C) hypertension model were investigated. METHODS: Wistar albino rats were divided into sham-operated (n = 8) or 2K1C groups, in which rats received either resveratrol (10 mg/kg per day, i.p., n = 8), or saline (n = 8) starting at Week 3 after the surgery and continuing for the following 6 weeks. Indirect blood pressure recordings and echocardiographic images were made to evaluate cardiac function. At the end of Week 9 the animals were decapitated and plasma, heart, kidney and brain were taken for biochemical assays, while aortic rings were prepared for vascular reactivity studies. KEY FINDINGS: 2K1C hypertension resulted in increased blood pressure, aortic hypercontractility and reduced left ventricular function, leading to increased lipid peroxidation and myeloperoxidase activity, concomitant with significant reductions in tissue glutathione, superoxide dismutase, Na+/K+-ATPase and catalase activities in the cardiac, renal and brain tissues, indicating the presence of oxidative tissue damage in peripheral target organs. Elevated plasma levels of lactate dehydrogenase, creatine kinase, as well as reduced plasma levels of antioxidant capacity and nitric oxide further verified the severity of oxidative injury. A 6-week treatment with resveratrol reversed all the measured parameters, ameliorated hypertension-induced oxidative injury in the target organs and improved cardiovascular function. CONCLUSIONS: Resveratrol improved cardiovascular function through the augmentation of endogenous antioxidants and the inhibition of lipid peroxidation by maintaining a balance in oxidant/antioxidant status, which also ameliorated hypertension-induced oxidative injury in the cardiac, renal and cerebral tissues.

Renal zinc clearance/glomerular filtration rate ratio as an indicator of marginal zinc deficiency associated with iron deficiency in childhood.

OBJECTIVE: To evaluate the usefulness of renal zinc clearance/glomerular filtration rate ratio (R(ClZn)/GFR) as an indicator of marginal zinc deficiency that is generally associated with iron deficiency in childhood. METHODS: Zinc status was evaluated in 36 iron-deficient children (22 boys and 14 girls) who ranged in age from 1 to 10 years using serum zinc concentration and U(Zn/Cr) and R(ClZn)/GFR ratios. The results were compared with the zinc status of 36 similar-aged healthy children (24 boys and 12 girls). RESULTS: Serum zinc concentrations were 96.72 +/- 2.13 microg/dL and 93.93 +/- 1.95 microg/dL in iron-deficient and healthy subjects, respectively (p > 0.05). U(Zn/Cr) ratios were 0.54 +/- 0.04 microg/mg and 0.88 +/- 0.04 microg/mg (p < 0.0001); R(ClZn)/GFR ratios were 2.27 x 10(-3) +/- 0.20 and 3.32 x 10(-3) +/- 0.20 (p < 0.001) in iron-deficient and healthy subjects, respectively. Individual values of R(ClZn)/GFR and U(Zn/Cr) ratios correlated with hemoglobin (Hb) concentrations (r = 0.34, p < 0.01 and r = 0.26, p < 0.05). Data grouped according to the ranges of Hb concentrations and R(ClZn)/GFR and U(Zn/Cr) ratios fit the following equations: The statistically significant difference in U(Zn/Cr) and R(ClZn)/GFR ratios between groups indicates decreased urinary estimation of marginal zinc deficiency, whereas no change was observed in serum zinc concentrations. According to the regression equation, it can be postulated that the R(ClZn)/GFR ratio is a linear function of Hb concentration and the U(Zn/Cr) ratio. CONCLUSION: R(ClZn)/GFR ratio was a reliable indicator for reduction in urinary zinc excretion; it estimated the marginal zinc deficiency associated with iron deficiency. The R(ClZn)/GFR ratio can be calculated using one sample of blood and urine; thus it could serve as an alternative indicator of marginal zinc deficiency, especially in routine health care.

Genital prolapse in a newborn following resection of sacrococcygeal teratoma.

Neonatal genital prolapse usually occurs during the first few days of life and presents as a tumor mass protruding from the vulva. We present a 15-day-old female neonate who developed neonatal genital prolapse following the operation of sacral teratoma. We suggest that sacral teratoma operation may be a significant predisposing factor for genital prolapse in neonates and the neonatal vaginal prolapse may be one of the differential diagnoses of interlabial mass during the late neonatal period.

Melatonin improves cardiovascular function and ameliorates renal, cardiac and cerebral damage in rats with renovascular hypertension.

The effect of melatonin was investigated in an angiotensin II-dependent renovascular hypertension model in Wistar albino rats by placing a renal artery clip (two-kidney, one-clip; 2K1C), while sham rats did not have clip placement. Starting either on the operation day or 3 wk after the operation, the rats received melatonin (10 mg/kg/day) or vehicle for the following 6 wk. At the end of the nineth week, after blood pressure (BP) and echocardiographic recordings were obtained, plasma samples were obtained to assay lactate dehydrogenase (LDH), creatine kinase (CK), antioxidant capacity (AOC), asymmetric dimethylarginine (ADMA), and nitric oxide (NOx) levels. In the kidney, heart and brain tissues, malondialdehyde (MDA) and glutathione (GSH) levels, superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO) and Na(+)-K(+) ATPase activities were determined. 2K1C caused an increase in BP and left ventricular (LV) dysfunction. In hypertensive animals LDH, CK, ADMA levels were increased in plasma with a concomitant reduction in AOC and NOx. Moreover, hypertension caused a significant decrease in tissue SOD, CAT, and Na(+), K(+)-ATPase activities and glutathione content, while MDA levels and MPO activity were increased in all studied tissues. On the other hand, both melatonin regimens significantly reduced BP, alleviated oxidative injury and improved LV function. In conclusion, melatonin protected against renovascular hypertension-induced tissue damage and improved cardiac function presumably due to both its direct antioxidant and receptor-dependent actions, suggesting that melatonin may be of therapeutic use in preventing oxidative stress due to hypertension.

Resveratrol treatment protects against doxorubicin-induced cardiotoxicity by alleviating oxidative damage.

The possible protective effects of resveratrol (RVT) against cardiotoxicity were investigated in Wistar albino rats treated with saline, saline+doxorubicin (DOX; 20 mg/kg) or RVT (10 mg/kg)+DOX. Blood pressure and heart rate were recorded on the 1st week and on the 7th week, while cardiomyopathy was assessed using transthoracic echocardiography before the rats were decapitated. DOX-induced cardiotoxicity resulted in decreased blood pressure and heart rate, but lactate dehydrogenase, creatine phosphokinase, total cholesterol, triglyceride, aspartate aminotransferase and 8-OHdG levels were increased in plasma. Moreover, DOX caused a significant decrease in plasma total antioxidant capacity along with a reduction in cardiac superoxide dismutase, catalase and Na+,K+-ATPase activities and glutathione contents, while malondialdehyde, myelopreoxidase activity and the generation of reactive oxygen species were increased in the cardiac tissue. On the other hand, RVT markedly ameliorated the severity of cardiac dysfunction, while all oxidant responses were prevented; implicating that RVT may be of therapeutic use in preventing oxidative stress due to DOX toxicity.

Hyperbaric oxygen therapy decreases QT dispersion in diabetic patients.

Diabetes mellitus is frequently associated with the malignant ventricular arrhythmias and sudden death. The QT dispersion is the difference between the longest and shortest QT interval calculated from the standard 12-lead electrocardiogram. The QT dispersion is suggested as an index of myocardial electrical activity. An increase in QT dispersion is associated with the malignant ventricular arrhythmias and sudden cardiac death. Diabetic patients receive hyperbaric oxygen (HBO) therapy for non-healing lower extremity ulcers. The aim of this study was to determine the effect of HBO therapy on QT dispersion in diabetic patients. Thirty diabetic patients (18 male and 12 female, 59.9 +/- 10 years), who were planning to undergo ten sessions of HBO therapy in two weeks for non-healing lower extremity ulcers, were consecutively enrolled into the study. The 12-lead resting electrocardiography recordings were taken before the first HBO therapy and after the 10th HBO-therapy session. QT intervals were measured on electrocardiogram. QT intervals were corrected for heart rate by using Bazett's formula (corrected QT [QTc] = QT/ radical R - R [seconds]). QTc dispersion was significantly decreased from 59.8 +/- 17.4 msec to 52.2 +/- 15.5 msec after ten sessions of HBO therapy (p < 0.05). However, maximum QTc, minimum QTc and mean QTc did not change significantly after HBO therapy. We have concluded that HBO therapy may reduce the risk of malignant ventricular arrhythmia and sudden cardiac death in diabetic patients when applied repetitively.

Allopurinol improves endothelial function and reduces oxidant-inflammatory enzyme of myeloperoxidase in metabolic syndrome.

OBJECTIVE: In this study, we tested in patients with metabolic syndrome whether allopurinol through decreasing oxidative stress improves endothelial function, and ameliorates inflammatory state represented by markers of myeloperoxidase, C-reactive protein (CRP) and fibrinogen. METHODS: In a randomized, double-blind fashion; subjects with metabolic syndrome were treated with allopurinol (n = 28) or placebo (n = 22) for one month. Before and after treatment, blood samples were collected and the flow-mediated dilation (FMD) and isosorbide dinitrate (ISDN)-mediated dilation of the brachial artery were performed. RESULTS: Baseline clinical characteristics of the allopurinol and placebo groups demonstrated no differences in terms of clinical characteristics, endothelial function and inflammatory markers. After the treatment with allopurinol, FMD was increased from 8.0 +/- 0.5 % to 11.8 +/- 0.6% (P < 0.01), but there were no change in the placebo group. In both groups, ISDN-mediated dilation is unaffected by the treatment. As a marker of oxidative stress, allopurinol significantly reduced malondialdehyde. Moreover, myeloperoxidase levels were reduced by the treatment with allopurinol (56.1 +/- 3.4 ng/ml vs. 44.4 +/- 2.4 ng/ml, P < 0.05) but there were no change in the placebo group. Surprisingly, neither CRP nor fibrinogen levels were affected by the treatment in both groups. CONCLUSION: Xanthine oxidoreductase inhibition by allopurinol in patients with metabolic syndrome reduces oxidative stress, improves endothelial function, ameliorates myeloperoxidase levels and does not have any effect on CRP and fibrinogen levels.

Hyperbaric oxygen therapy does not potentiate doxorubicin-induced cardiotoxicity in rats.

The current use of doxorubicin is regarded as an absolute contraindication for hyperbaric oxygen (HBO2) therapy because of the increased risk of cardiotoxicity. The aim of this study was to investigate whether additional exposure to HBO2 during the course of doxorubicin treatment would further increase the cardiotoxicity of doxorubicin in rats. Female Wistar rats were treated with either HBO2 (n = 10) or doxorubicin (n = 8) or a combination of both treatments (n = 10) for 4 consecutive weeks and followed up for an additional 4 weeks. Cardiomyopathy was evaluated using two-dimensional and M-mode echocardiography at baseline, at the fourth, sixth and eighth weeks, and by histopathological investigation of the rat hearts at the eighth week. Doxorubicin treatment significantly reduced ejection fraction and fractional shortening (P < 0.001) and caused severe histopathological injury (P < 0.05) indicating development of cardiotoxicity. Although the combination of doxorubicin and HBO(2) also markedly reduced ejection fraction and fractional shortening (P < 0.001), this reduction was significantly less than that of doxorubicin treatment (P < 0.05). HBO2 therapy also attenuated doxorubicin-induced histopathological changes in rat hearts (P < 0.05). HBO2 alone did not alter echocardiographic parameters or histopathological findings (P > 0.05). In conclusion, HBO2 therapy does not potentiate doxorubicin-induced cardiotoxicity in rats. Cardioprotection conferred by HBO2 against doxorubicin warrants further investigation.