Dürdane Kolankaya

Influence of vitamin C on bisphenol A, nonylphenol and octylphenol induced oxidative damages in liver of male rats.

The purpose of this study was to investigate whether bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP) induce oxidative stress in the liver of male rats and co-administration of vitamin C can prevent any possible oxidative stress. Wistar male rats were divided into seven groups (vehicle, BPA, NP, OP, BPA+C, NP+C, OP+C). BPA, OP and NP groups (25 mg kg(-1)day(-1)) were administered orally to rats three times a week for 50 days. In BPA+C, NP+C, OP+C groups, vitamin C (60 mg kg(-1)day(-1)) was administered along with BPA, OP and NP (25 mg kg(-1)day(-1)) treatments. Aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), thiobarbituric acid-reactive substances (TBARS) were increased, glutathione (GSH) levels were decreased in treatment groups. AST, ALT, LDH and TBARS levels were increased whereas GSH levels were decreased in BPA+C, NP+C and OP+C groups compared to BPA, NP, and OP groups, respectively. Hepatic necrosis and congestion were observed in livers of rats treated. In conclusion, the present results demonstrate that BPA, NP, and OP cause oxidative damage by disturbing the balance between ROS and antioxidant defenses system in liver of male rats. Vitamin C co-administration along with BPA, NP, OP aggravates the damage in liver of male rats.

Protective effects of Turkish propolis on alcohol-induced serum lipid changes and liver injury in male rats

Abstract The chemical content of Turkish Castanea sativa propolis is investigated, along with its protective effect against alcohol-induced oxidative stress. The ethanol-propolis extract, at dose of 200 mg/kg body weight/day, was given, by gavage, to male rats for 15 days. At the end of the treatment, serum lipid levels, activities of liver enzymes and other biochemical parameters were measured. HDL level decreased and LDL level increased in the alcohol group, while HDL level increased and LDL level decreased in the alcohol+propolis group. There were decreases in cholesterol and triglyceride levels in the alcohol+propolis group. Also, there were decreases in ALP and AST enzyme activities, but LDH enzyme activity increased in the propolis treatment group compared to the alcohol group. No toxic effects of Turkish C. sativa propolis were found, while it caused an increase in HDL level and a decrease in LDL level. We suggest that these effects are protective against degenerative diseases and against alcohol-induced oxidative stress via free radicals.

Protective Effect of Rutin on the Ischemia/Reperfusion Induced Damage in Rat Kidney

Reactive oxygen species (ROS) are suggested to participate in ischemia/reperfusion (I/R) injury in the kidney. This study was designed to investigate the effect of rutin, a bioflavonoid, in I/R induced renal injury. Wistar albino rats were unilaterally nephrectomized, and 2 wk later they were subjected to 45 min of left renal pedicle occlusion followed by 3h of reperfusion. Either rutin (1g/kg) or saline was administrated (i.p.) 1h prior to ischemia. At the end of the reperfusion period, kidney samples were taken for determination of renal malondialdehyde (MDA) and glutathione (GSH) levels, manganese-superoxide dismutase (MnSOD) activity and histological examination. Serum creatinine, blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) concentrations were measured for the evaluation of renal function. I/R caused a significant decrease in GSH level and MnSOD activity, which was accompanied by a significant increase in MDA level of kidney tissues. Similarly, serum BUN and creatinine levels, as well as LDH were elevated in the I/R group compared with the control group. Pretreatment of rats with rutin (1g/kg/ i.p.) significantly attenuated renal dysfunction, reduced elevated MDA levels, and restored the depleted MnSOD activity and GSH levels. These beneficial changes in the biochemical parameters were also associated with parallel changes in histopathological appearance. These findings suggest that ROS play a causal role in I/R induced renal injury, and that rutin exerts renal-protective effects, probably by inhibiting ROS and antioxidant activities.

The effect of vitamin C on bisphenol A, nonylphenol and octylphenol induced brain damages of male rats.

Bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP) are endocrine-disrupting chemicals that has been shown to exert both toxic and estrogenic effects on mammalian cells. The aim of this study was to investigate if BPA, NP and OP induce oxidative stress on the brain tissue of male rats and if co-administration of vitamin C, an antioxidant, can prevent any possible oxidative stress. The male rats were divided into seven groups as control (vehicle), BPA, NP, OP, BPA+C, NP+C, OP+C. BPA, OP and NP (25 mg/(kg day)) were administrated orally to male Wistar rats for 45 days. In vitamin C co-administration groups (BPA+C, NP+C, OP+C), vitamin C (60 mg/(kg day)) were administrated orally along with BPA, OP and NP (25 mg/(kg day)) treatments. The rats in the control group received olive oil orally. The final body and absolute organ weights of treated rats did not show any significant difference when compared with the control group. Also, there were no significant difference in relative organ weights of BPA, NP, OP, BPA+C and NP+C groups when compared with control group. Only, relative organ weights were increased significantly in OP+C group compared with control group. Decreased levels of reduced glutathione (GSH) were found in the brains of BPA, NP, OP treated rats. The end product of lipid peroxidation, malondialdehyde (MDA), appeared at significantly higher concentrations in the BPA, NP, and OP treated groups when compared to the control group. On the other hand, there were no changes in the brain MDA and GSH levels of BPA+C, NP+C and OP+C groups compared with BPA, NP and OP treatment groups, respectively. In histopathologic examination, the vitamin C co-administrated groups had much more hyperchromatic cells in the brain cortex than that observed in the groups treated with only BPA, NP, and OP. The results of this study demonstrate that BPA, NP and OP generate reactive oxygen species that caused oxidative damage in the brain of male rats. In addition, vitamin C co-administration along with BPA, NP, and OP aggravates this oxidative damage in the brain of rats.

The effect of sub-acute and sub-chronic exposure of rats to the glyphosate-based herbicide Roundup.

Roundup is a glyphosate-based herbicide that includes 78.5% glyphosate and surfactant at lower toxic concentrations. Glyphosate is an organophosphorated non-selective agrochemical widely used in many countries including Turkey and acts after the sprout in a systemic way. The objective of this study was to analyze toxic effects of the herbicide Roundup in rat liver. Animals were treated with 56mg/kg (p.o.) and 560mg/kg (p.o.) of Roundup (78% glyphosate+surfactant) each day, during 5 and 13 weeks. Hepatotoxicity was monitored by quantitative analysis of the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) activities and measured amount of serum lipoprotein (LDL, HDL), total cholesterol and creatinine were used as the biochemical markers of liver damages. Besides the biochemical analysis, we also investigated liver tissues histopathologically. Sub-chronic treatment, starting from the low and high doses of Roundup, it was observed that there were mild effects on activity of ALT, AST and LDH enzymes indicating the hepatic toxicity induced by Roundup. It was found that the mild effects were different on the enzymes in male and female rats of treatment groups. Also it was found some difference in serum lipoprotein (LDL, HDL) and t-cholesterol. There was no difference creatinine value between control and treatment groups but it was observed that degenerative formation such as mononuclear cell infiltration and congestion of the liver tissues of treatment groups.

Organochlorine pesticide reidues and their toxic effects on the environment and organisms in Turkey

Persistent toxic substances (PTSs) appear in most urbanized coastal areas of the world, accumulating in water, sediments, and biota, where they cannot be eliminated efficiently, and their derivatives can be highly toxic. Like many other countries, Turkey is also facing problems concerning pesticides and other PTS residues. BHC and alpha, beta, gamma and delta isomers of HCH were determined in 16 samples of surface and ground waters and mussels in the Middle Black Sea Region, and the concentrations of PCB and organochlorine (OC) pesticide residues were analysed in the eastern Aegean Sea water and fish samples. PCBs were not detected in Mullus barbatus living in the Aegean Sea, and its derivatives were detected in low levels. Thirteen OC pesticides were determined in water, sediment, fish, and water birds in the Göksu Delta. Thirteen OC pesticides were analysed in the Sarıyar Dam Lake, in Sakarya basin, five lakes in Central Anatolia, and the Meriç Delta in water sediment and fish samples. Some of these pesticides were found in more or less all of the samples. Micro-organisms in soil and some saprophyte fungi detoxify chlorinated hydrocarbons by dechlorinating them. The toxicity of degraded metabolites of these insecticides, for which the Cl amounts have been reduced, decreased consequently, and toxic effects also reduced in mice when Cl was removed. Mixed cultures of micro-organisms isolated from agricultural soils were used to degrade endosulphan, carbaryl, and malathion. This result indicates that these chemicals break down in soil, resulting in a significant decrease in its toxic effects. Toxic substances cause acute, sub-chronic, and chronic effects in the environment on biota. The hermit ibises, an endemic migratory bird species, no longer visit the Birecik district. In Turkey, the reason for this is also thought to be the usage of organochlorine pesticide sprays in agricultural areas of the district. In recent years, studies have been conducted on the activation of PTSs and Cyt P450 mono-oxygenase enzymes in indicator fish species. One of these studies has been conducted on the bottom-feeding fish that live in Izmir Bay. The outcomes showed a significant decrease in the EROD activity in fish (mullet and the benthic fish common sole are used as biomonitors for PAHs and PCB-type pollutants) that have been harvested from six different stations along the Bay from the city borders towards the inner parts of the Aegean Sea. The effects of OCPs have been determined by other studies in Sarıyar Dam Lake and Meriç Delta. An increase in the EROD activity has been determined in fish living in these environments.

Pro-oxidant effect of vitamin C coadministration with bisphenol A, nonylphenol, and octylphenol on the reproductive tract of male rats.

This study was performed to investigate whether bisphenol A (BPA), nonylphenol (NP), and octylphenol (OP) induce oxidative stress on the reproductive tract of male rats and if coadministration of vitamin C can prevent any possible oxidative stress. Wistar male rats were divided into seven groups as control (vehicle; olive oil), BPA, NP, OP, BPA+C, NP+C, and OP+C. BPA, OP, and NP groups (25 mg/kg/day) were administered orally to rats three times a week for 45 days. In BPA+C, NP+C, and OP+C groups, vitamin C (60 mg/kg/day) was administered orally along with BPA, OP, and NP (25 mg/kg/day) treatments. Malondialdehyde (MDA) appeared at significantly higher concentrations in BPA-, NP-, and OP-treated groups, when compared to control group. No significant decrease was observed in testes MDA levels of vitamin C coadministrated groups, compared with BPA, NP, and OP treatment groups. Decreased levels of reduced glutathione (GSH) were found in testes of BPA-, NP-, OP-treated rats. No significant increase was observed in testes GSH levels of BPA+C, NP+C, and OP+C groups, compared with BPA, NP, and OP treatment groups. Histological examination showed that vitamin C coadministrated groups had much more congestion areas, atrophy, and germinal cell debris in testes than those observed in other groups. Abnormal sperm percentages of BPA, BPA+C, NP+C, and OP+C groups were increased. In conclusion, the present results demonstrated that BPA, NP, and OP generate reactive oxygen species that cause oxidative damage in testes of rats. Coadministration of vitamin C aggravates this damage.

Vitamin C coadministration augments bisphenol A, nonylphenol, and octylphenol induced oxidative damage on kidney of rats

The aim of this study was to investigate whether bisphenol A (BPA), nonylphenol (NP), and octylphenol (OP) induce oxidative stress on the kidney tissue of male rats and whether coadministration of vitamin C, an antioxidant, can prevent any possible oxidative stress. The Wistar male rats were divided into seven groups, including control, BPA, NP, OP, BPA+C, NP + C, OP +C. BPA, NP, and OP (25 mg/kg/day) was administered alone; vitamin C (60 mg/kg/day) was administered along with BPA, OP, and NP to the rats for 50 days. There was a decrease in serum concentration of blood urea nitrogen (BUN) in NP and OP groups compared with control group. Vitamin C coadministration with BPA, NP, and OP did not produce significant increase in BUN concentration in BPA +C, NP+ C, and OP + C group as compared with BPA, NP, and OP groups, respectively. The lowest serum creatinine activity and the highest lactate dehydrogenase (LDH) activity was present in kidney of BPA+C, NP+C and OP+C groups compared with BPA, NP, and OP groups. The malondialdehyde (MDA) levels were significantly higher while glutathione (GSH) levels were lower in treatment groups than controls. Furthermore, an increase was observed in MDA levels whereas a decrease was observed in GSH levels in BPA+ C, NP + C, and OP+ C groups compared with BPA, NP, and OP groups, respectively. These finding are in accordance with immunohistochemical staining of MDA and GSH. Histopathological examination of the kidneys of rats in BPA, OP, NP, BPA+ C, NP + C, and OP+ C groups revealed necrotic lesions, congestion, and mononuclear cell infiltration. In conclusion BPA, NP, and OP might induce oxidative damage in kidney of rats. In addition, coadministration of vitamin C with BPA, NP, and OP to male rats augments this damage in the kidney of male rats.

Inhibiting inducible nitric oxide synthase with rutin reduces renal ischemia/reperfusion injury.

BACKGROUND Nitric oxide (NO) seems to play an important role during renal ischemia/reperfusion (I/R) injury. We investigated whether rutin inhibits inducible nitric oxide synthase (iNOS) and reduces 3-nitrotyrosine (3-NT) formation in the kidneys of rats during I/R. METHODS Wistar albino rats were nephrectomized unilaterally and, 2 weeks later, subjected to 45 minutes of left renal pedicle occlusion followed by 3 hours of reperfusion. We intraperitoneally administered L-N6-(1-iminoethyl)lysine (L-NIL; 3 mg/kg) for 30 minutes or rutin (1 g/kg) for 60 minutes before I/R. After reperfusion, kidney samples were taken for immunohistochemical analysis of iNOS and 3-NT. We measured plasma nitrite/nitrate and cyclic guanosine monophosphate (cGMP) to evaluate NO levels. RESULTS Ischemia/reperfusion caused plasma cGMP to increase significantly. Similarly, plasma nitrite/nitrate was elevated in the I/R group compared with the control group. Histochemical staining was positive for iNOS and 3-NT in the I/R group. Pretreatment with L-NIL or rutin significantly mitigated the elevation of plasma cGMP and nitrite/nitrate. These changes in biochemical parameters were also associated with changes in immunohistochemical appearance. Pretreatment with L-NIL or rutin significantly decreased the incidence and severity of iNOS and 3-NT formation in the kidney tissues. CONCLUSION Our findings suggest that high activity of iNOS causes renal I/R injury, and that rutin exerts protective effects, probably by inhibiting iNOS.

Determination of organochlorine pesticide residues in water, sediment, and fish samples from the Meriç Delta, Turkey

This study had been carried out between May 2002 and August 2003 in Meriç Delta, Turkey which is located at a site where the Meriç River falls to the Agean Sea. Residues of organochlorine pesticides (OC) in surface water, sediment, and fish (Cyprinus carpio) samples from Meriç Delta were analysed by gas chromatography. The results of the study showed that all analysed 20 organochlorine pesticides and their residues have been widespread throughout the study area. According to the results, it was found that the concentrations of these selected organochlorine pesticides in fish (Cyprinus carpio) samples were higher than in water and sediment samples. Because of the low water solubility of the organochlorine compounds, it is expected that any organochlorine pesticides present in the study area, will be preferably adsorbed to sediment or bioaccumulated in fish. The α- and β-HCH were the predominant HCH isomers in all analysed fish samples and ranged between 319.5 and 968.15 ng g−1 and between 397.5 and 876.4 ng g−1, respectively. The concentration levels of p,p′-DDT (ranging from 2.68 to 52.45 ng g−1) in all analysed fish samples were consistently higher than its metabolite p,p′-DDE, indicating a recent use of this organochlorine pesticide in the area. We have analysed the distribution characteristics of individual organochlorine pesticide and found that α-, β-HCH, p,p′-DDT p,p′-DDE, β-endosulphan, heptachlore epoxide, and endrin ketone were the most common organochlorine pesticides contaminants in the study area.