Abdulkadir Yildirim

SPIRULINA PLATENSIS PROTECTS AGAINST GENTAMICIN-INDUCED NEPHROTOXICITY IN RATS

The present study aimed to investigate the protective effect of Spirulina platensis (SP) on gentamicin sulphate (GS)‐induced changes in the levels of lipid peroxidation and endogenous antioxidants in the kidney of rats. Sprague‐Dawley rats were treated in separate groups as follows for 7 consecutive days: control (C), gentamicin sulphate (100 mg/kg i.p.) (GS), Spirulina platensis (1000 mg/kg orally) (SP) and Spirulina platensis (1000 mg/kg orally) plus gentamicin sulphate (100 mg/kg i.p.) (SP + GS). The degree of protection was evaluated by determining the effects of Spirulina platensis on malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPX) and nitric oxide (NO), and plasma creatinine and urea levels were estimated in kidney homogenates to evaluate antioxidant activity, and the kidney was histologically examined as well. Spirulina platensis elicited significant nephroprotective activity by decreasing lipid peroxidation (MDA) and elevated the levels of GSH, SOD, GPX, NO, creatinine and urea. Furthermore, these biochemical observations were supplemented by histological examination of the rat kidneys. In conclusion, the present study indicates a very important role of reactive oxygen species (ROS) and the relation to renal dysfunction and point to the therapeutic potential of Spirulina platensis in gentamicin sulphate induced nephrotoxicity. Copyright

Serum Adiponectin Levels in Patients with Esophageal Cancer

OBJECTIVE The aim of the study was to investigate a possible relationship between serum levels of adiponectin and clinicopathological characteristics in esophageal cancer. This is the first report evaluating serum adiponectin levels in patients with esophageal cancer. METHODS Sixty-two patients with esophageal cancer and thirty healthy subjects were included in the study. Adiponectin levels were determined by an enzyme-linked immunosorbent assay kit. RESULTS The mean serum adiponectin level in the cancer group was significantly low compared with the adiponectin level in the healthy control group. Furthermore, adiponectin levels of the patients gradually decreased with increase in tumor stage. The patients with adenocarcinoma of the esophagus had significantly lower values of serum adiponectin than patients with squamous cell carcinoma. CONCLUSION We concluded that decreased circulating adiponectin levels may play a role in the progression and/or development of esophageal cancers. However, for clinical use of serum adiponectin in terms of early diagnosis and treatment, further studies should be performed.

Increased Serum Levels of Tumor Necrosis Factor Alpha in Lichen planus

Background: Lichen planus (LP) is a common, pruritic, inflammatory mucocutaneous disease. There are several opinions and approaches to the etiopathogenesis of LP. Immunologic mechanisms almost certainly mediate its development. T-cell-mediated immunity plays the major role in triggering the clinical expression of the disease. The cytokines that are produced by lymphocytes also play an important role in the development of LP. Objective: The goal of our study was to investigate the possible role of tumor necrosis factor α (TNF-α) in the pathogenesis of LP. Methods: Serum TNF-α levels were determined with the enzyme-linked immunosorbent sandwich assay method in the sera of 40 patients suffering from LP and in those of 40 healthy controls. Results: The serum levels of TNF-α were found to be significantly higher in the patient group compared to the healthy controls (patients: 35.64 ± 9.59 pg/ml, controls: 15.6 ± 3.97 pg/ml, p < 0.001). Conclusion: Our results revealed that TNF-α might play a major role in the pathogenesis of LP.

Correlation of P-selectin and lipoprotein(a), and other lipid parameters in preeclampsia

Abstract Preeclampsia is a pregnancy specific disorder and is thought to be associated with generalized endothelial dysfunction. P-selectin, an adhesion molecule, mediates the interaction of monocytes, platelets, and endothelial cells. Increased P-selectin levels and altered lipid and lipoprotein metabolism were reported in preeclampsia and during pregnancy. In order to investigate the relationship between serum P-selectin and lipoprotein(a), and other lipid parameters, 28 preeclampsia [13 severe (group I) and 15 mild preeclampsia (group II), 15 healthy pregnant (group III) and 20 non-pregnant (group IV)] women were investigated. Serum P-selectin, lipoprotein(a), total cholesterol, triglyceride, and high density lipoprotein cholesterol were measured and low-density lipoprotein cholesterol was derived. Serum P-selectin concentrations were consistently and significantly higher in the severe preeclampsia group than in the mild preeclampsia, healthy pregnancy, and non-pregnant control groups (P<0.0001, for all). The mild preeclampsia group also had increased serum P-selectin concentrations compared with the healthy pregnancy group and non-pregnant controls (P<0.05 and P<0.0001, respectively). Serum P-selectin and lipoprotein(a) levels revealed a significant and linear increase with the severity of preeclampsia. There were also significant (in groups I and II) and borderline (in groups III and IV) correlations between P-selectin and total cholesterol. The present study suggests that P-selectin may be an additional risk marker for preeclampsia, and may be useful in distinguishing women with mild and severe preeclampsia and normal pregnancy.

Influence of Smoking on Serum and Milk Malondialdehyde, Superoxide Dismutase, Glutathione Peroxidase, and Antioxidant Potential Levels in Mothers at the Postpartum Seventh Day

The aim of the study was to investigate simultaneously serum and milk malondialdehyde (MDA) levels, superoxide dismutase (SOD), glutathione peroxidase (GPx) activities, and antioxidant potential (AOP) in active-smoking, passive-smoking, and nonsmoking mothers and to search if there is any difference between serum and milk oxidant/ antioxidant status caused by smoking. According to their smoking status, 60 mothers (age range: 20–35 yr) were classified into one of three groups: the active-smoking mothers (n=15), the passive-smoking mothers (n=22), and the nonsmoking mothers (n=23). Serum and milk MDA, SOD, GPx, and AOP values were determined in mothers on the postpartum seventh day by the spectrophotometric method. Serum Zn and Cu concentrations were determined by atomic absorption spectrophotometry (AAS). There was no significant difference in serum samples with respect to MDA (p=0.17), SOD (p=0.51) and AOP (p=0.36) levels, but there was a significant difference in serum GPx (p=0.002) levels among the study groups. The significant differences were also found in milk samples in terms of MDA (p=0.002) and SOD (p=0.011), but not in GPx (p=0.11) and AOP (p=0.29) levels among the study groups. No significant difference was seen in serum zinc concentration (p=0.49), but copper concentration differed significantly among the groups (p=0.005). These observations suggest that human milk is more vulnerable to oxidative stress and lipid peroxidation than serum samples in smoking mothers, even if they are passive smokers.

Protective effect of L-carnitine against cisplatin-induced liver and kidney oxidant injury in rats

The present study was designed to investigate the protective effects of L-carnitine (LC) on changes in the levels of lipid peroxidation and endogenous antioxidants induced by cisplatin (cis-diamminedichloroplatinum II, CDDP) in the liver and kidney tissues of rats. Twenty-four Sprague Dawley rats were equally divided into four groups of six rats each: control, cisplatin, L-carnitine, and L-carnitine plus cisplatin. The degree of protection produced by L-carnitine was evaluated by determining the level of malondialdehyde (MDA). The activity of glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione S-transferase (GST), and superoxide dismutase (SOD) were estimated from liver and kidney homogenates, and the liver and kidney were histologically examined as well. L-carnitine elicited significant liver and kidney protective activity by decreasing the level of lipid peroxidation (MDA) and elevating the activity of GSH, GSHPx, GST, and SOD. Furthermore, these biochemical observations were supported by histological findings. In conclusion, the present study indicates a significant role for reactive oxygen species (ROS) and their relation to liver and kidney dysfunction, and points to the therapeutic potential of LC in CDDP-induced liver and kidney toxicity.

Plasma values of oxidants and antioxidants in acute brain hemorrhage : Role of free radicals in the development of brain injury

The levels of oxidants xanthine oxidase (XO), nitric oxide (NO), and malondialdehyde (MDA) and of the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GRD) were determined in plasma within 24 h after onset of hemorrhagic stroke in 17 patients (9 men and 8 women, aged 60.7±11.5 yr) and in 20 healthy controls (12 men and 8 women, aged 62.5±8.3 yr). Compared to controls, the plasma SOD and total superoxide scavenger activi ties (TSSA) were significantly lower and the NO levels were significantly higher among the stroke patients. XO showed a slight, nonsignificant increase in the patients, but the levels of MDA, NSSA, GRD, and GSH-Px did not show any significant differences between the two groups. The hemorrhage volume was negatively, correlated with the initial score of the Glasgow Coma Scale and a positive correlation with lethal outcome, but it did not correlate significantly with any of the measured parameters. The results suggest that free radicals might play a role in the development of brain injury following brain hemorrhage.

Effect of Smoking on Neonatal and Maternal Serum and Breast Milk Leptin Levels

Maternal smoking is considered to be a risk factor for low birth weight. It is hypothesized that alteration in leptin concentration may be associated with reduced fetal growth. In this study, we assess the effect of smoking during pregnancy on maternal and neonatal serum leptin concentrations, and also on breast milk leptin levels. When the infants were brought to routine physical examination at 7 days old, blood samples and breast milk specimens were taken for leptin measurement from mothers who smoked during pregnancy and their newborns. Nonsmoking mothers and their infants were recruited randomly over the same period as a control group. Maternal age, number of pregnancy, weight of the mothers, birth weight, and gestational age of the infants were similar in both groups (p > 0.05). There was no significant difference between groups in maternal serum and breast milk leptin levels (p = 0.14 and p = 0.96, respectively). However, serum leptin levels were found significantly lower in neonates born to smoking mothers compared with infants born to nonsmoking mothers (p = 0.02). Our findings suggest that maternal smoking dose not have an effect on maternal serum and breast milk leptin levels but decreases neonatal serum leptin concentration independent of birth weight.

Paraoxonase 1 gene polymorphisms, paraoxonase/arylesterase activities and oxidized low-density lipoprotein levels in patients with migraine

The vascular endothelial dysfunction has been implicated in the pathogenesis of migraine. Oxidized low‐density lipoprotein (ox‐LDL) may impair endothelial function. Paraoxonase‐1 (PON‐1) prevents oxidative modification of LDL cholesterol (LDL‐C). So we investigated serum PON‐1 and arylesterase (ARE) activities, PON‐1 55 L/M and 192Q/R polymorphisms and the serum lipid profile in patients with migraine. Biochemical parameters and PON‐1 polymorphism analyses were assessed in 104 patients with migraine and 86 healthy subjects. Ox‐LDL was detected by ELISA, and polymorphisms were determined using PCR–restriction fragment length polymorphism analysis. Patients with migraine had lower PON‐1 and ARE activities (p < 0·001, for both) and higher ox‐LDL and LDL‐C levels (p < 0·001, for both) and ox‐LDL: LDL‐C ratio (p < 0·005) than the controls. The genotype distribution and the allele frequencies for PON‐1 55 L/M and 192Q/R polymorphisms were not different among the study populations. The results of our current study indicate that migrainous patients have decreased serum PON‐1 and ARE activities and increased serum ox‐LDL levels, which may have a clinical importance in the treatment of migraine. Copyright

Antioxidant Status in Blood of Obese Children: The Relation between Trace Elements, Paraoxonase, and Arylesterase Values

Obesity is known to lead to complications involving several systems. The basic mechanism in obesity-related complications is chronic inflammation and increased oxidative stress. Trace element levels in obese children may vary due to poor nutritional habits. The purpose of this study was to investigate the relation between serum paraoxonase (PON1) and arylesterase (ARE) levels, markers of the oxidant–antioxidant balance in the body, and serum zinc (Zn), copper (Cu), manganese (Mn), and selenium (Se) concentrations in obese children. Fifty-seven overweight patients aged 6–17 and 48 age- and sex-matched healthy children were included in the study. Serum PON1 and ARE activity levels were measured, together with Cu, Zn, Mn, Se, total cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein, very low-density lipoprotein, glucose, aspartate amino transferase, and alanine amino transferase levels. PON1 and ARE activity levels were significantly lower in obese patients compared to those in healthy individuals (P < 0.05). Various changes were determined in Cu, Zn, Mn, and Se levels between the study and control groups (P < 0.05). In terms of the relation between trace elements and PON1 and ARE levels, a significant positive correlation was determined between serum Se and PON1 levels in the study group (P < 0.05, r = 0.31). No significant correlation was determined between other trace element levels and PON1 and ARE levels (P > 0.05). In conclusion, the detection in our study of a positive correlation between Se and PON1 levels in obese children may be significant in terms of showing a relation between Se and antioxidant systems in obese children.