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The effects of caffeine on the renal antioxidant activity in rats [Ratlarda böbrek antioksidan aktivitesi üzerine kafeinin etkileri]

Demir E.O. | Demirtaş C.Y. | Paşaoğlu Ö.T.

Article | 2016 | Turkish Journal of Biochemistry41 ( 3 ) , pp.216 - 222

Objective: In our study, the short-term effects of caffeine on the renal antioxidant activity in rats were investigated. Methods: Caffeine was given orally at two different doses: 30 mg/kg and 100 mg/kg (a high non-toxic dose). The current study included 30 rats, which were divided into 3 groups: a control group and two caffeine-treated groups. Group 1 was given caffeine at 30 mg/kg and Group 2 was given caffeine at 100 mg/kg for 14 days. We measured advanced oxidation protein products (AOPP), malondialdehyde (MDA) and nitric oxide (NO) levels in the kidney tissue following caffeine administration. In addition, we also evaluated sup . . .eroxide dismutase (SOD), and glutathione S transferase (GST) activities in the kidney tissue. Results: Our results showed that caffeine administration decreased lipid peroxidation and advanced oxidation protein products in kidney. Especially, MDA levels in the kidney tissue of the caffeine-treated groups decreased significantly as a result of the dose. NO levels in the kidney tissue of the caffeine-treated groups were higher than those in the control group. GST activities in the kidney tissue of rats in the caffeine groups also increased significantly. In our study, we did not observe significant changes in renal SOD activities upon caffeine consuption. Conclusion: These results show that short-term consumption of two different doses of caffeine may protect against oxidative stress in the kidney tissue of rats. This effect is related to the caffeine dosage. Determining the mechanisms and antioxidant effects of caffeine at suitable dose requires advanced animal and human studies. © 2016, Turkish Biochemistry Society. All rights reserved Daha fazlası Daha az

Dexmedetomidine did not reduce the effects of tourniquet-induced ischemia-reperfusion injury during general anesthesia

Bostankolu E. | Ayoglu H. | Yurtlu S. | Okyay R.D. | Erdogan G. | Deniz Y. | Hanci V.

Article | 2013 | Kaohsiung Journal of Medical Sciences29 ( 2 ) , pp.75 - 81

Ischemia reperfusion injury causes the release of free oxygen radicals. Free oxygen radicals initiate the production of toxic metabolites, such as malondialdehyde (MDA), through the lipid peroxidation of cellular membranes. Following lipid peroxidation, the antioxidant enzyme system is activated against reactive oxygen species (ROS) and attempts to protect cells from oxidative damage. There is a balance between the scavenging capacity of antioxidant enzymes and ROS. Because of this balance, the total antioxidant capacity (TAC) measurement is a sensitive indicator of the overall protective effects of the antioxidants. Alpha2 receptor . . . agonists are effective in preventing hemodynamic reactions during extremity surgeries by preventing the release of catecholamines secondary to tourniquet application. They have also been shown to possess preventive effects in various ischemia-reperfusion injury models. In our study, we examined the effects of dexmedetomidine on tourniquet-induced ischemia-reperfusion injury in lower extremity surgeries performed under general anesthesia. The effects of dexmedetomidine were measured with serum MDA and TAC levels. We studied 60 adult American Society of Anesthesiologists (ASA) physical status I or II patients undergoing one-sided lower extremity surgery with tourniquet. The patients were randomly divided into two groups. Group D was administered a dexmedetomidine infusion at a rate of 0.1 µg/kg/minute -1 for 10 minutes prior to induction and then at 0.7 µg/kg/hour-1 until 10 minutes before the end of the operation. The control group (Group C) received a saline infusion of the same amount and for the same period of time. General anesthesia was induced with thiopental, fentanyl, and rocuronium and maintained with nitrous oxide and sevoflurane in both groups. Venous blood samples were obtained before the administration of the study drugs (basal) at 1 minute before tourniquet release and at 5 and 20 minutes after tourniquet release (ATR). In both groups, MDA levels decreased at 5 and 20 minutes ATR when compared with the basal values (p < 0.05). TAC levels decreased at 1 and 5 minutes ATR and then returned to basal values at 20 minutes ATR (p < 0.05). In reference to the prevention of lipid peroxidation in tourniquet-induced ischemia-reperfusion injury, the results from the two groups in our study showed that dexmedetomidine did not have an additional protective role during routine general anesthesia. Copyright © 2012, Kaohsiung Medical University. Published by Elsevier Taiwan LLC. All rights reserved Daha fazlası Daha az

Exposure to streptomycin alters oxidative and antioxidative response in larval midgut tissues of Galleria mellonella

Büyükgüzel, Ender | Kalender, Yusuf

Article | 2009 | Pesticide Biochemistry and Physiology94 ( 02.Mar ) , pp.112 - 118

Although antibiotics have different molecular modes of actions, increasing evidence for their secondary effects suggests that they disturb cellular homeostasis by generating free radical intermediates that trigger lipid peroxidation, which leads to oxidative stress. Streptomycin is an antibiotic insecticide used to control pest insects and microbial diseases of agricultural crops. We investigated the biochemical basis for pro-oxidative effects of streptomycin in the midgut tissues of greater wax moth, Galleria mellonella (L.) seventh-instar larvae by measuring content of the oxidative stress indicator, malondialdehyde (MDA), and ant . . .ioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST) and glutathione peroxidase (GPx)] and transaminases [alanine aminotransferase (ALT), aspartate aminotransferase (AST)] activities. The insects were reared from first-instar larvae on artificial diets containing 0.001, 0.01, 0.1 or 1.0 g streptomycin per 100 g of diets. The supplementation of streptomycin at high concentrations to the diets caused oxidative stress as evidenced by the elevation of MDA content, SOD and GPx activities, accompanied by the concurrent depletion of CAT and GST activities. The streptomycin-induced oxidative stress was also accompanied by decreases of transaminases activities in midgut tissues. We found a significant negative correlation of MDA contents with GST activities in the larval midgut tissues. These results suggest that exposure to dietary streptomycin resulted in oxidative stress which could impact midgut digestive physiology at the expense of impairment of antioxidant and transaminases enzymes in G. mellonella larvae. © 2009 Elsevier Inc. All rights reserved Daha fazlası Daha az

The effects of boric acid-induced oxidative stress on antioxidant enzymes and survivorship in Galleria mellonella

Hyršl, Pavel | Büyükgüzel, Ender | Büyükgüzel, Kemal

Article | 2007 | Archives of Insect Biochemistry and Physiology66 ( 1 ) , pp.23 - 31

Larvae of the wax moth, Galleria mellonella (L.), were reared from first instar on a diet supplemented with 156, 620, 1,250, or 2,500 ppm boric acid (BA). The content of malondialdehyde (MDA, an oxidative stress indicator), and activities of the antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and glutathione peroxidase (GPx)] were determined in the fat body and hemolymph in the 7th instar larvae and newly emerged pupae. Relative to control larvae, MDA was significantly increased in larval hemolymph, larval and pupal fat body, but decreased in the pupal hemolymph. Insects reared on di . . .ets with 156-and 620-ppm BA doses yielded increased SOD activity but 1,250- and 2,500-ppm doses resulted in decreased SOD activity in larval hemolymph. SOD activity was significantly increased but CAT was decreased in the larval fat body. High dietary BA treatments led to significantly decreased GST activity. However, they increased GPx activity in larval hemolymph. Dietary BA also affected larval survival. The 1,250- and 2,500-ppm concentrations led to significantly increased larval and pupal mortality and prolonged development. In contrast, the lowest BA concentration increased longevity and shortened development. We infer that BA toxicity is related, at least in part, to oxidative stress management. © 2007 Wiley-Liss, Inc Daha fazlası Daha az

Protective effects of Vitamins C, alone or in combination with Vitamin A, on endotoxin-induced oxidative renal tissue damage in rats

Kanter M. | Coskun O. | Armutcu F. | Uz Y.H. | Kizilay G.

Article | 2005 | Tohoku Journal of Experimental Medicine206 ( 2 ) , pp.155 - 162

This study was designed to investigate the protective effects of vitamin C and vitamin A on oxidative renal tissue damage. Male Wistar rats were given an intraperitoneal injection of 0.5 ml saline (control) or 0.5 ml solution of lipopolysaccharide (10 mg/kg), which caused endotoxemia. Immediately (within 5 min) after the endotoxin injection, the endotoxemic rats were untreated or treated with intraperitoneal injection of vitamin A (195 mg/kg bw), vitamin C (500 mg/kg bw) or their combination. After 24 hours, tissue and blood samples were obtained for histopathological and biochemical investigation. Endotoxin injection caused renal t . . .issue damage and increased erythrocyte and tissue malondialdehyde (MDA) and serum nitric oxide (NO), urea and creatinine concentrations, but decreased the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities compared to the parameters of control animals. Treatment with vitamin C or with vitamins C and A significantly decreased the MDA levels and serum NO, urea and creatinine levels, recovered the antioxidant enzyme activities (SOD, GSH-Px and CAT), and prevented the renal tissue damage in endotoxemic rats. In contrast, vitamin A alone did not change the altered parameters except for creatinine levels. Notably, the better effects were observed when vitamins A and C given together. It is concluded that vitamin C treatment, alone or its combination with vitamin A, may be beneficial in preventing endotoxin-induced oxidative renal tissue damage and shows potential for clinical use. © 2005 Tohoku University Medical Press Daha fazlası Daha az

Biochemical stress indicators of greater wax moth exposure to organophosphorus insecticides

İçen, Ender | Armutçu, Ferah | Büyükgüzel, Kemal | Gürel, Ahmet

Article | 2005 | Journal of Economic Entomology98 ( 2 ) , pp.358 - 366

Although acetylcholinesterase (AChE) is the primary target of organophosphorus insecticides (OPs), increasing evidence regarding their secondary effects suggests that OPs disturb homeostasis of insects by generating free radical intermediates that trigger lipid peroxidation. We therefore investigated alterations in lipid peroxidation product, malondialdehyde (MDA) content, and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, in conjunction with AChE activity as biochemical stress indicators in greater wax moth, Galleria mellonella (L.) larvae for OPs methyl parathion (MP) and ethyl parathion (EP). The . . .effects of MP and EP were first investigated by rearing the young larvae on an artificial diet containing 0.01, 0.1, 1, 10, and 100 ppm of each insecticide. Second, the mature larvae were injected with 0.05, 0.5, 5, 50, and 500 ng of insecticides for determining the changes in biochemical stress responses. The diet with lowest level of MP significantly decreased the activities of all measured enzymes, whereas it increased MDA content. However ALT and AST were significantly higher in the larvae reared with the diet with high levels of MP than in control larvae. All tested levels of MP resulted in a decrease in AChE activity. The lowest level of EP in diet (0.01 ppm) significantly increased ALT activity, whereas it reduced that of AChE. This insecticide at 0.1 ppm resulted in reduced AST activity, but 1 ppm in diet elevated AST activity and MDA content. EP at 0.1 ppm and higher levels in the diet reduced ALT activity. All dietary EP levels significantly decreased AChE activity. ALT, AST, and AChE were lower in larvae fed with the diet containing 100 ppm ethyl parathion compared with larvae on control diet. MP at 50 ng per larva increased ALT and AST activities from 35.42 ± 0.74 and 26.34 ± 0.83 to 203.57 ± 1.09, and 122.90 ± 1.21 U/g, respectively, when the mature larvae were injected. All injected doses of EP dramatically reduced both ALT and AST activities, but only the lowest and highest levels of this insecticide decreased AChE activity. The lowest level of this insecticide also significantly increased MDA content in larvae. High levels of both insecticides increased MDA content. We observed a significant higher increase in MDA content in the larvae reared with 10 ppm EP (102.16 ± 1.57 nmol/g protein) than the control group (30.28 ± 1.42 nmol/g protein). These results suggest that OPs caused the metabolic and synaptic dysfunctions in greater wax moth and alter its biochemical physiology in response to oxidative stress. © 2005 Entomological Society of America Daha fazlası Daha az

The evaluation of serum cystatin C, malondialdehyde, and total antioxidant status in patients with metabolic syndrome

Demircan N. | Gürel A. | Armutcu F. | Ünalacak M. | Aktunç E. | Atmaca H.

Article | 2008 | Medical Science Monitor14 ( 2 ) , pp.358 - 366

Background: This study was designed to determine if serum cystatin C (Cys C) levels are affected by metabolic syndome and whether they correlate with lipid peroxidation and total antioxidant status (TAS) in this disorder. Material/Methods: Cases with metabolic syndrome diagnosed according to the ATP III criteria (18 females, 12 males) were compared with healthy control subjects (20 females, 17 males) matched by age and gender. Plasma Cys C, malondialdehyde (MDA), and TAS levels were studied. Results: Compared with the controls, Cys C and MDA levels were significantly higher (p

Serum iron concentrations, lipid peroxidation and superoxide dismutase activity in Turkish iron miners

Armutcu F. | Gurel A. | Aker A.

Article | 2004 | Environmental Geochemistry and Health26 ( 1 ) , pp.1 - 4

The effects of iron exposure, on serum iron, serum superoxide dismutase (SOD), a free radical scavenger, and plasma malondialdehyde (MDA), a lipid peroxidation parameter, were investigated in Turkish iron miners, office workers and healthy control subjects. Serum iron levels in both miner and office workers groups were higher than those of healthy controls (p < 0.05). There were higher mean values of plasma MDA levels in both iron miners and office workers compared to controls (p < 0.05). Serum SOD activity in the miner group was lower than that of controls (p < 0.05). These results suggested that elevated MDA levels in both miners . . .and office workers were the result of an increased production and/or decreased catabolism of MDA in chronic iron exposure. These changes in MDA metabolism may be due to iron-induced lipid peroxidation in the blood and related body compartments. © 2004 Kluwer Academic Publishers Daha fazlası Daha az

Influence of smoking on serum and milk malondialdehyde, superoxide dismutase, glutathione peroxidase, and antioxidant potential levels in mothers at the postpartum seventh day

Ermis B. | Yildirim A. | Örs R. | Tastekin A. | Ozkan B. | Akcay F.

Article | 2005 | Biological Trace Element Research105 ( 01.Mar ) , pp.27 - 36

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 det . . .ermined 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. © Copyright 2005 by Humana Press Inc Daha fazlası Daha az

Influence of smoking on maternal and neonatal serum malondialdehyde, superoxide dismutase, and glutathione peroxidase levels

Ermis B. | Ors R. | Yildirim A. | Tastekin A. | Kardas F. | Akcay F.

Article | 2004 | Annals of Clinical and Laboratory Science34 ( 4 ) , pp.405 - 409

This cohort study investigated postnatal serum malondialdehyde (MDA), Superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels in 14 active-smoking, 14 passive-smoking, and 15 non-smoking mothers and their newborns on day 7 post-partum. No significant differences were noted among the study groups with respect to MDA (p = 0.63) or SOD levels (p = 0.98) in either the mothers or their infants. However, there were significant differences among the study groups with respect to serum GPx activities in both the mothers (p = 0.028) and the infants (p = 0.039). When GPx activities were analyzed separately in both mothers and infan . . .ts, a significant difference was noted only between the infants of smoking mothers and the infants of non-smoking mothers (p = 0.015). In conclusion, there was a significant increase in GPx activities of smoking mothers and their infants, suggesting that they may have been exposed to more oxidant stress Daha fazlası Daha az

Effects of increasing ratio of progesterone in estrogen/progesterone combination on total oxidant/antioxidant status in rat uterus and plasma

Hekimoglu A. | Bilgin H.M. | Kurcer Z. | Ocak A.R.

Article | 2010 | Archives of Gynecology and Obstetrics281 ( 1 ) , pp.23 - 28

Purpose: The relationship between increasing ratio of progesterone in estrogen/progesterone combination and oxidative stress (OS) was investigated. Methods: Thirty non-pregnant Wistar Albino female rats were divided into five groups and bilaterally ovariectomized (Ovx) except sham group. Groups: Sham + 0.3 cc seaseme oil, Ovx + 0.3 cc seaseme oil, Ovx + estradiol propionate (E2) (1 µg/kg), Ovx + E2 + medroxyprogesterone acetate (MPA) 1 mg/kg, Ovx + E2 + MPA 20 mg/kg. Hormones were applied for three consecutive days after 28 days of ovariectomy. Their uteri and blood samples were collected and nitric oxide (NO), malondialdehyde (MDA) . . ., total oxidative status (TOS) and total antioxidant capacity (TAC) levels were determined. Results: E2 + MPA1 treatment decreased NO, MDA and TOS levels and increased TAC levels in uterus. Plasma NO levels elevated in all groups and MDA production increased due to E2 treatment when compared to ovariectomy. E2 + MPA20 treatment increased TOS levels, while TAC levels decreased when compared to ovariectomy in plasma. Conclusions: Using E2 plus low dose progesterone may prevent pathologies resourced of OS. © 2009 Springer-Verlag Daha fazlası Daha az

Purine catabolic enzymes and nitric oxide in patients with recurrent aphthous ulceration

Gurel A. | Altinyazar H.C. | Unalacak M. | Armutcu F. | Koca R.

Article | 2007 | Oral Diseases13 ( 6 ) , pp.570 - 574

Objectives: Recurrent aphthous ulceration (RAU) is one of the most common oral mucosal disorders found in humans. Although the exact etiology of RAU is unkown, local and systemic conditions, and genetic, immunologic, and infectious factors all have been identified as potential etiopathogenic agents. The aim of our study was to compare serum xanthine oxidase (XO) and adenosine deaminase (AD) activities, and malondialdehyde (MDA), nitric oxide (NO) and uric acid (UA) levels in a group of patients affected by RAU and in a group of healthy controls. Subjects and methods: A total of 26 patients with minor RAU were included in the study. . . .Twenty-six healthy volunteers were selected to form the control group. AD and XO activities, and UA, NO, and MDA levels were studied in the serum samples of all patients and controls. Results: Serum XO and AD activities, and MDA, NO, and UA levels were significantly higher in RAU patients than in controls. Conclusion: Increased XO and AD activities, NO and UA levels and lipid peroxidation were thought to take part in the pathogenesis of RAU. Hence the effects of XO inhibitors in the treatment of RAU should be evaluated in future studies. © 2007 The Authors Daha fazlası Daha az

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