Fikret Karatas

Antioxidant vitamin levels in term and preterm infants and their relation to maternal vitamin status.

BACKGROUND Lipid peroxidation plays a vital role in the pathogenesis of many neonatal complications. Preterm babies are especially predisposed to lung diseases and retinopathy, probably due to a deficiency in their antioxidant systems. Vitamins E, A, and C are part of the natural antioxidant defense systems. We aimed to determine the levels of vitamins E, A, and C in maternal and cord blood plasma of term and preterm infants and to investigate the relationships between these levels. METHODS In the present study we determined vitamin E, A, and C levels in the umbilical cord blood of term (n = 30) and preterm (n = 22) infants and their mothers by HPLC. Blood samples were taken during delivery. RESULTS Levels of lipid soluble antioxidant vitamin E and A in cord blood were lower than maternal values (p <0.01, p <0.05, respectively). Conversely, the level of water-soluble vitamin C was higher in cord blood than in maternal level (p <0.05). Significantly higher levels of vitamins E, A, and C were found in term babies as compared with those born preterm (p <0.05). CONCLUSIONS There was a positive correlation between maternal and cord blood levels of vitamins E and A (r = 0.775, r = 0.725, respectively). In conclusion, preterm babies have fewer lipid-soluble antioxidant vitamins in their serum compared to term infants. Therefore, it is possible to postulate that preterm infants are more susceptible to oxidative stress.

The vitamin and selenium contents of apricot fruit of different varieties cultivated in different geographical regions

Abstract High-pressure liquid chromatographic and fluorometric methods were utilized to determine the vitamin (A, C, E and β-carotene) and selenium levels in apricot fruit. The vitamins (A, C, and E), β-carotene and selenium levels of both fresh and sulphurized (sulphur-dried) apricot fruit from several common cultivars and wild type, grown in different regions, were analysed. The effects of post-harvest processing, regional difference and cultivar type on the levels of these nutrients were investigated. Cultivated varieties possessed significantly higher vitamin C (P

Comparison of the concentration of trace metals (Ni, Zn, Co, Cu and Se), Fe, vitamins A, C and E, and lipid peroxidation in patients with prostate cancer.

Abstract The anticarcinogenic and antioxidant properties of vitamins A, C, E and pro- or antioxidant properties of trace metals have recently attracted increased attention. We examined the levels of antioxidant vitamins (A, C and E), selenium and malondialdehyde (MDA), and trace metals (Fe, Ni, Zn, Co and Cu) in patients with prostate cancer. In total, 41 subjects (21 controls and 20 prostate cancer patients) were included in the study. The levels of trace elements and Fe in whole blood were determined by atomic absorption spectrophotometry. Serum levels of Se were determined using a fluorimetric method, while a HPLC method was used for serum levels of vitamins and MDA. The levels of vitamins A and E were significantly lower and MDA levels were significantly higher (p<0.001) in patients with prostate cancer compared to controls. Serum vitamin C was significantly lower in patients with prostate cancer when compared to controls (p<0.01). Moreover, Se and Zn levels were also significantly lower, and levels of Ni, Co, and Cu were higher (p<0.001) in patients with prostate cancer than in controls. Fe levels were not significantly different in patients compared to controls (p>0.05). Our findings, together with the results of previous animal studies, suggest that the administration of vitamins A, C, and E, and Se and Zn may be beneficial in the prevention and treatment of human prostate cancer.

The levels of glutathione peroxidase, vitamin A, E, C and lipid peroxidation in patients with transitional cell carcinoma of the bladder

To assess the levels of erythrocyte glutathione peroxidase (GSH‐Px), and the serum levels of antioxidant vitamins (A, E and C), selenium and malondialdehyde (MDA) in patients with transitional cell carcinoma (TCC) of the bladder.

Effects of exogenous metallothionein on acute cadmium toxicity in rats.

The present study was carried out to evaluate the effect of exogenously administered metallothionein (MT) to rats exposed to high cadmium levels. A total of 72 rats were used in the study. The animals were divided into three groups: controls, Cd administered, and Cd+MT. Cadmium was administered by subcutaneous injection of cadmium(II) chloride at a dose of 3.5 mg/kg for 7 d. In addition to CdCl2, 30 μmol/kg MT was administered to the second group of rats (group II). Control rats received 0.5 mL physiologic serum via subcutaneous injection. Eight rats from each group were sacrificed on the 1st, 3rd, 5th, and 7th day after administration of the compounds. Liver, kidney, and blood samples were harvested. Levels of malondialdehyde (MDA), glutathione peroxidase (GSH-Px), serum ALT, AST, BUN, ALP, creatinine, and urea were measured. MDA levels in group I were observed to increase starting from d 1 compared to group II (p<0.05). Although MDA levels in group II were higher than controls (p<0.05), they were lower, especially in liver and blood, compared to group II. Erythrocyte GSH-Px activity levels were determined to decrease starting from d 1 in both groups (p<0.05). Decreases in GSH-Px activity levels in group II were less than group I. Serum creatinine levels in both groups were increased significantly compared to controls (p<0.05); the increase in group I was higher than group II. Serum ALT, AST, and ALP levels in group I increased to very high levels compared to controls, whereas increases in group II were at moderate levels (p<0.05). Although serum BUN levels were determined to be reduced, there was no significant change among the groups. Serum urea levels in both groups were higher than controls. Based on our results, it is possible to postulate that exogenous MT can act as antioxidant against Cd toxicity and lipid peroxidation.

Comparison of plasma malondialdehyde, glutathione, glutathione peroxidase, hydroxyproline and selenium levels in patients with vitiligo and healthy controls

Background: The etiology and pathophysiologic mechanism of vitiligo are still unclear. The relationship between increased oxidative stress due to the accumulation of radicals and reactive oxygen species and the associated changes in blood and epidermal component of vitiliginous skin have been reported many times. We investigated the possible changes of plasma malondialdehyde, glutathione, selenium, hydroxyproline and glutathione peroxidase activity levels in patients with vitiligo in order to evaluate the relationship between oxidative stress and etiopathogenesis of vitiligo. Materials and Methods: Plasma malondialdehyde, glutathione, hydroxyproline and glutathione peroxidase activity levels were measured by spectrophotometric methods, and HPLC was used for measurement of selenium concentrations. Results: Our results showed increased malondialdehyde, hydroxyproline and glutathione peroxidase activity levels in plasma of vitiligo group (P < 0.05). Conclusion: Support of antioxidant system via nonenzymatic antioxidant compounds and antioxidant enzymes may be useful to prevent of melanocyte degeneration which occur due to oxidative damage in vitiligo.

Comparison of Serum Malondialdehyde Levels Determined by Two Different Methods in Patients With COPD: HPLC or TBARS Methods

Thus, the determination of the oxidative stress gradually gets more important during the course of chronic diseases. The results of recent studies have indicated that during the exacerbation of COPD, antioxidant capacity is lower and the levels of lipid peroxidation products are higher than those in age-matched healthy subjects. 2,5,6 These lipid peroxidation products easily create reactive carbon compounds. The most important one is malondialdehyde (MDA). The determination of the level of MDA is the most practical and confidant method used for detecting and screening oxidative stress usually. 7 Malondialdehyde levels may serve as a marker of prognosis and of the success of treatment of the exacerbation of COPD. 2,5,6 Absolute level of free MDA in serum may be also determined with HPLC as a new method without using any reactive component 8 while total MDA level in serum is commonly determined by the TBARS process, which is currently used as a spectrophotometric method. Furthermore, in this method, it is stated that TBA forms complexes with MDA and the other many subtrates such as metal ions and

Simultaneous quantification of acylated and desacylated ghrelin in biological fluids

This study reports simultaneous quantification of both acylated and desacylated forms of ghrelin in biological samples, utilizing a reverse-phase high-performance liquid chromatography (HPLC) system. The HPLC assay was also compared with RIA assays in use. Biological samples (serum, saliva, urine, milk) known for the presence of ghrelin were collected from a total of eight post-partum women and eight male volunteers. Analysis of ghrelin with HPLC was also validated for linearity, precision, detection limit and accuracy. An elution time of 6 min was observed for pure (commercial) desacylated human ghrelin and for the same form of the hormone from all body fluids studied. The elution time for acylated pure human ghrelin and that in body fluids, however, was around 16 min. The mean recovery rate was over 90% for both forms with no significant interference. The lowest detectable levels for acylated and desacylated ghrelin with the method used here were 11 (+/-2) and 14 (+/-3) pg mL(-1), respectively. Given its simplicity, accuracy, time and cost-effectiveness, the HPLC method described here for determination of two forms of ghrelin (active and inactive) might prove useful for certain diagnostic purposes.

Ghrelin in plants: What is the function of an appetite hormone in plants?

In the present work, we provide compelling evidence for the expression of a ghrelin-like peptide hormone that has only been associated with animals, in various plant tissues. Ghrelin, the appetite stimulating hormone, has been identified from a number of different species including humans, rat, pig, mouse, gerbil, eel, goldfish, bullfrog and chicken. The study here was conducted using an immunohistochemistry assay to screen whether plants have any ghrelin immunoreactivity. In this respect, Prunus x domestica L. and Marus alba were examined. Immunohistochemistry results showed that there is a strong human ghrelin immunoreactivity substance in the parenchyma cells of these plants. This was entirely unexpected since this hormone was considered to be present solely in animals. Thus, this study is the first to report the presence of a peptide with ghrelin-like activity in plants, a finding that has only been observed in the animal kingdom. RIA analysis confirmed that these plants contain significant amounts of this substance. Furthermore, reverse-phase HPLC analyses of plant extracts showed an elution characteristic of the peptide identical to that of human ghrelin. In general, fruit from both plants had higher levels of the peptide than the vegetative parts.

Protective effect of octreotide on intra-tracheal bleomycin-induced oxidative damage in rats

The present study is aimed at determining the effect of parenteral octreotide against oxidative damage caused by intra-tracheal bleomycin (BLM) administration. A total of 30 male Wistar rats randomly divided into three groups (control, bleomycin alone, and bleomycin and octreotide) were used in the study. A group of animals received a single dose of intra-tracheal bleomycin (7.5mg/kg). Animals in another group, which also received intra-tracheal bleomycin, were given 82.5 microg/kg octreotide via i.m. injection for a week. Animals in the control group received neither bleomycin nor octreotide. All animals were sacrificed at the end of the experiment. Serum levels of malondialdehyde, vitamins A, E, and C, selenium levels were determined. In addition, glutathion peroxidase activity levels in erythrocytes were also determined. Malondialdehyde levels and glutathion peroxidase activity were increased whereas antioxidant vitamin levels were decreased significantly in animals that received only bleomycin compared to control animals (p<0.05). The values in rats that received bleomycin and octreotide were found to be closer to the control group (p<0.05). Selenium levels in animals that received only bleomycin were determined to be reduced compared to controls (p<0.05). On the other hand, selenium levels in bleomycin and octreotide groups were similar to control values in (p<0.05). In conclusion, bleomycin induces a severe stress and more importantly increases the amount of free radicals whereas octreotide administration reduces this oxidative damage significantly.