Browsing by Author "Alak, Gonca"

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Antioxidant Potential of Ulexite in Zebrafish Brain: Assessment of Oxidative Dna Damage, Apoptosis, and Response of Antioxidant Defense System
(Springernature, 2021) Alak, Gonca; Ucar, Arzu; Parlak, Veysel; Yeltekin, Asli Cilingir; Ozgeris, Fatma Betul; Atamanalp, Muhammed; Turkez, Hasan
In recent years, because of its significant biological roles, the usage of boron has been started in animal feeding. In this research, it was aimed to investigate the ulexite's action mechanism on the zebrafish brain with an evaluation of the oxidative parameters. The adult zebrafish were exposed to four ulexite doses (5, 10, 20, and 40 mg/l) in a static test apparatus for 96 h. For assessing the oxidative responses, multiple biochemical analyses were performed in brain tissues. The results indicated the supporting potential of low ulexite doses on the antioxidant system (< 40 mg/l) and that low-dose ulexite does not lead to oxidative stress in the zebrafish brain. Again, our results showed that low ulexite concentrations did not cause DNA damage or apoptosis. As a final result, in aquatic environments, ulexite (a boron compound) can be used in a safe manner, but it would be useful at higher concentrations to consider the damages of the cells that are probable to develop because of the oxidative stress
Assessment of 8-Hydroxy Activity, Gene Expression and Antioxidant Enzyme Activity on Rainbow Trout (Oncorhynchus Mykiss) Tissues Exposed To Biopesticide
(Elsevier Science inc, 2017) Alak, Gonca; Ucar, Arzu; Parlak, Veysel; Yeltekin, Ash Cilingir; Tas, Ismail Hakki; Olmez, Dogukan; Yanik, Telat
The goal of this study was to determinate toxicity mechanism of biopesticide with antioxidant enzymes parameters such as superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) and malondialdehyde (MDA) levels, oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG)), transcriptional changes of heat shock protein 70 (HSP70), and cytochromes P4501A (CYP1A), sod, cat, and gpx in liver and gill tissues of Oncorhynchus mykiss. For this aim, plant-based (natural pesticides, azadirachtin (AZA)) and synthetic pesticides (deltamethrin (DLM)) were exposed on the fish at different concentrations (0.0005 and 0.00025 ppm of DLM; 0.24 and 0.12 ppm of AZA) for 21 days. According to the results of the study, the activity of SOD, CAT and GPx decreased, but malondialdehyde (MDA) level and activity of 8-OHdG increased in the gill and liver of rainbow trout (p < 0.05). Additionally sod, cat and gpx were down regulated; HSP70 and CYP1A were up regulated for transcriptional observation. The downwards regulation of antioxidant (sod, cat and gpx) and the upregulation of HSP70 and CYP1A was obvious with doses of AZA or DLM (p < 0.05). The findings of this study suggest that biopesticide can cause biochemical and physiological effects in the fish gill and liver by causing enzyme inhibition, an increase in 8-OHdG levels and changes in both transcriptional parameters (sod, cat, gpx, HSP70 and CYP1A). We found that excessive doses of plant -based pesticide are nearly as toxic as chemical ones for aquatic organisms. Moreover, 8-OHdG, HSP70 and CYP1A used as a biomarker to determinate toxicity mechanism of biopesticide in aquatic environment.
Borax Alleviates Copper-Induced Renal Injury Via Inhibiting the Dna Damage and Apoptosis in Rainbow Trout
(Springernature, 2019) Alak, Gonca; Yeltekin, Asli Cilingir; Ucar, Arzu; Parlak, Veysel; Turkez, Hasan; Atamanalp, Muhammed
The aim of this study was to determine the therapeutic potential of borax against copper in the kidney tissue of the rainbow trout fed with added borax (BX) (1.25, 2.5, and 5 mg/kg) and/or copper (Cu) (500,1000 mg/kg) contents. For this purpose, two treatment groups had designed, and glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) enzyme activities were determined. Besides, oxidative DNA damage (8-hydroxy-2 '-deoxyguanosine, 8-OHdG), caspase-3, and malondialdehyde (MDA) levels were assessed in kidneys of all treatment groups. In molecular pathway, hsp70, CYP1A, and antioxidant gene expression levels were determined. In the results of the analysis, antioxidant enzyme activity and gene expression were increased; 8-OHdG, caspase-3, and MDA levels were decreased in groups fed with borax supplemented feeds compared to the copper-treated group. The alterations among the groups were found as significant (p < 0.05). CYP1A and hsp70 gene expressions were upregulated in copper and copper combined groups (p < 0.05). The findings of present research showed that borax had alleviative effect on copper-induced toxicity and could be used as an antidote in fish nutrition.
Borax Attenuates Oxidative Stress, Inflammation, and Apoptosis by Modulating Nrf2/Ros Balance in Acrylamide-Induced Neurotoxicity in Rainbow Trout
(Taylor & Francis Ltd, 2025) Turkez, Hasan; Alak, Gonca; Ozgeris, Fatma Betul; Cilingir Yeltekin, Asli; Ucar, Arzu; Parlak, Veysel; Atamanalp, Muhammed
Acrylamide (ACR) can have adverse environmental effects because of its multiple applications. Relevant scientific literatures of the existence of ACR residues in foods following processing steps have raised concern in the biochemistry, chemistry and safety of this vinyl substance. The interest has focused on the hepatotoxicity of ACR in animals and humans and on the ACR content mitigation and its detoxification. Borax (BX), as a naturally occurring antioxidant featured boron compound, was selected in this investigation to assess its possible neuro-protective potential against ACR-induced neurotoxicity. Nrf2 axis signaling pathways and detoxification response to oxidative stress after exposure to ACR in brains of rainbow trout, and the effect of BX application on reducing ACR-induced neurotoxicity were investigated. Rainbow trout were acutely exposed to ACR (12.5 mg/L) alone or simultaneously treated with BX (0.75 mg/L) during 96h. The exposed fish were sampled at 48th and 96th and oxidative stress response endpoints, 8-OHdG, Nrf2, TNF-alpha, caspase-3, in addition to IL-6 activities and the levels of AChE and BDNF in brain tissues of rainbow trout (Oncorhynchus mykiss) were evaluated. Samples showed decreases in the levels of ACR-mediated biomarkers used to assess neural toxicity (SOD, CAT, GPx, AChE, BDNF, GSH), increased levels of MDA, MPO, DNA damage and apoptosis. ACR disrupted the Nrf2 pathway, and induced neurotoxicity. Inhibited activities' expressions under simultaneous administration experiments, revealed the protective effects of BX against ACR-induced toxicity damage. The obtained data allow the outline of early multi-parameter signaling pathways in rainbow trout
Borax Exerts Protective Effect Against Ferrocene-Induced Neurotoxicity in Oncorhynchus Mykiss
(Elsevier Gmbh, 2022) Yeltekin, Ash Cilingir; Ucar, Arzu; Parlak, Veysel; Ozgeris, Fatma Betul; Turkez, Hasan; Esenbuga, Nurinisa; Alak, Gonca
Background: In recent years, therapeutic targets and the development of new drugs have shifted research towards inflammatory and oxidative stress pathways. Ferrocene (FcH) is a stable, small molecule that exhibits immunostimulatory and anti-tumor properties by a different mechanism and is effective at low doses in oral administration. However, it was surprising that there has been no performed investigation using FcH on aquaculture. On the other hand, recent papers reveal the key biological functions and health benefits due to daily boron intake in animals and humans. Therefore, we investigated the neurotoxic damage potential of FcH and its related neurotoxicity action mechanism in aquatic environments. In addition, the protective potential of borax (BX, or sodium borate) were evaluated againt in vivo neurotoxicity by FcH. Methods: Neurotoxicity assessment was performed in rainbow trout brain tissue, acutely under semi-static conditions via determining a vide range of parameters including catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) activities as well as glutathione (GSH), myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA levels), DNA damage (8-OHdG), apoptosis (caspase 3), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), nuclear factor erythroid-2 (Nrf-2), acetylcholinesterase (AChE) and brain-derived neurotrophic factor (BDNF) levels. In addition, the LC50 96 h level of FcH was determined for the first time in rainbow trout in this study. Results: In the obtained results, while FcH caused inhibition in enzyme activities, it showed an inducing effect on MDA, MPO, BDNF, Nrf2, TNF-alpha and IL-6 levels. It was determined that this oxidative damage related alterations were significantly different (p < 0.05) in comparison between FcH treated and controls. Again, the LC 50 96 h value in rainbow trout was determined as 11.73 mg/L, which is approximately 5% less than the value given for freshwater fish (12.3 mg/L). On the contrary, it was observed that BX has a mitigating effect on FcH-induced neurotoxicity. Conclusion: The present study suggests that borax may be useful for preventing or alleviating neurotoxicity induced by environmental contaminants or toxic chemicals.
Borax Relieved the Acrylamide-Induced Hematotoxic, Hepatotoxic, Immunotoxic and Genotoxic Damages in Rainbow Trout by Regulating Apoptosis and Nrf2 Signaling Pathway
(Elsevier Science inc, 2022) Atamanalp, Muhammed; Turkez, Hasan; Yeltekin, Asli cilingir; Ozgeris, Fatma Betuel; Ucar, Arzu; caglar, Ozge; Alak, Gonca
Acrylamide(AA) is a compound with wide usage areas including paper, dyes, and plastics industries. Due to its broad spectrum and water solubility suggest that this vinyl compound may cause serious environmental problems. AA was shown to exhibit neurotoxic, immunotoxic, reproductive toxicant as well as carcinogenic potency on animals. Especially in recent years, the therapeutic effects of boron and boron containing compounds like borax(BX), ulexite(ULX) and colemanite(COL) had been reported. However, the ameliorative potential by boron compounds against AA-induced toxicities had not been investigated yet. Therefore, in this investigation rainbow trout were exposed acutely to AA in the presence and absence of BX. The hematological indices and genotoxic end-points were examined in the fish blood tissue. In addition to oxidative stress response, the levels of DNA damage, CASP3, TNF-alpha, Nrf-2 as well as IL-6 amounts were determined in both blood and liver tissues of fish. The obtained results executed that AA induced toxic conditions in both tissues. In fact, an increase in the amount of oxidative stress and ROS, and a decrease in GSH levels were observed. AA exposure led to an increase in CASP3levels and 8-OHdG formation. It was also found that Nrf-2 pathway contributed to the initiation of oxidative stress that associated with AA-induced toxicity. On the contrary, our findings indicated that co-exposure of BX with AA elicited oxidative stress and cell death. In a conclusion BX was suggested as a useful and effective natural agent for the prevention and early treatment of AA toxicity in fish.
Determination of Fipronil Toxicity by Different Biomarkers in Gill and Liver Tissue of Rainbow Trout (Oncorhynchus Mykiss)
(Springer, 2020) Ucar, Arzu; Parlak, Veysel; Ozgeris, Fatma Betul; Yeltekin, Asli Cilingir; Alak, Gonca; Atamanalp, Muhammed
Insecticides that disrupt the healthy functioning of the ecosystem have toxic potential on non-target organisms. Fish, an important component of the aquatic ecosystem, are exposed to these pesticides in different ways. The stress response is regarded as an adaptive mechanism that allows the fish to cope with the perceived stressor to maintain its normal or homeostatic state. This mechanism is determined by antioxidant parameters and oxidative stress indicators measured in gill and liver tissue of rainbow trout. Accordingly, the effects of fipronil (FP) insecticide on the physiology of rainbow trout (Oncorhynchus mykiss) were determined with using the different biomarkers (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), malondialdehyde (MDA), paraoxonase (PON), arylesterase (ARE), myeloperoxidase (MPO), 8-hydroxy-2-deoxyguanosine (8-OHdG)), and caspase 3 activity) in this study. Different doses of FP inhibited antioxidant enzyme activities in rainbow trout liver and gill tissues while inducing oxidative stress parameter (MDA, MPO, and 8-OHdG) levels. Also, caspase-3 activity was increased in liver and gill tissue, but this increase was statistically significant only in gill tissue (p < 0.05). When the results of the study were taken into consideration, it was concluded that different doses of FP insecticide caused physiological changes in rainbow trout and the studied parameters were usable biomarkers in explaining the adaptive response of stress factor.
The Effect of N-Acetylcysteine Supplementation on the Oxidative Stress Levels, Apoptosis, Dna Damage, and Hematopoietic Effect in Pesticide-Exposed Fish Blood
(Wiley, 2019) Ucar, Arzu; Ozgeris, Fatma Betul; Yeltekin, Asli Cilingir; Parlak, Veysel; Alak, Gonca; Keles, Mevlut Sait; Atamanalp, Muhammed
Cysteine is important for protein synthesis, detoxification, and diverse metabolic functions. However, cysteine metabolism has been poorly described in fish, and the role of the therapeutic effect in pesticide toxicology on aquatic organisms is unknown. The aim of this study was to determine the effects of regular cysteine treatment on the hematology, biochemistry, apoptosis, oxidative DNA damage, and antioxidant parameters in fish blood after chemical application. Therefore, fish were exposed to cypermethrin for 2 weeks. Then two different concentrations of N-acetylcysteine (NAC) were applied for a 4-day treatment period and compared with the group of the self-healing process. At the end of the treatment, the hematological index, blood biochemical parameters, paraoxonase (PON), arylesterase (ARE), and myeloperoxidase (MPO) activities in the fish blood samples were investigated. With regard to the hematological parameters, statistical differences were obtained except for mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) (P < 0.05). Enzyme activities (ARE, PON, and MPO), as well as some biochemical parameters (creatinin [Cre], alanine amino transferase, total glyceride, alkaline phosphatase, iron, calcium, low density lipoprotein-cholesterol [LDL-C], sodium, and potassium), were found to be importantly different among all groups at the P < 0.05 level, while 8-hydroxydeoxyguanosine and caspase-3 levels were determined to be high in the pesticide group but decreased significantly in NAC-treated groups (P < 0.05). According to the results of the study, acute cysteine treatment showed an ameliorative effect on the hematological index, biochemical parameters, PON, MPO, and ARE in the blood in the all the treatment group fish. The positive effect of NAC on protein synthesis, detoxification, and diverse metabolic functions against cypermethrin toxicity was more effective in 1.0mM NAC. NAC has an important therapeutic effect on pesticide-induced hematoxicity for fish in terms of all the data.
Hematological and Hepatic Effects of Ulexite in Zebrafish
(Elsevier, 2020) Alak, Gonca; Ozgeris, Fatma Betul; Yeltekin, Asli Cilingir; Parlak, Veysel; Ucar, Arzu; Caglar, Ozge; Atamanalp, Muhammed
The ulexite (UX), a borate mineral, is used as boron source and commonly used in various industrial processes. The hematological and hepatic effects of UX were investigated by exposing adult zebrafish to UX (5, 10, 20 and 40 mg/L) over 96 hours. The blood and liver tissues were taken at the end of the trial period then micronucleus (MN) rates, oxidative DNA damage (8-OHdG), apoptosis (Caspase-3), superoxide dismutase (SOD), catalase (CAT), glutathione pemxidase (GPx), myelopemxidase (MPO), paraoxonase (PON), arylesterase (AR) and lipid peroxidation (MDA) levels were determined. Genotoxic damage by UX occurred only at 40 mg/L in the blood MN assay. Oxidative stress, oxidative DNA damage and apoptosis in liver also occurred at this dose. Moreover, 5-20 mg/L doses led to decreases of DNA damage and apoptosis levels via promoting antioxidant system in liver tissues. UX exhibits beneficial roles on blood and liver tissues of zebrafish at relatively lower doses, which may be relevant to nutritional and medicinal industries.
Investigation of 8-Ohdg, Cyp1a, Hsp70 and Transcriptional Analyses of Antioxidant Defence System in Liver Tissues of Rainbow Trout Exposed To Eprinomectin
(Academic Press Ltd- Elsevier Science Ltd, 2017) Alak, Gonca; Yeltekin, Ash Cilingir; Tas, Ismail Hakki; Ucar, Arzu; Parlak, Veysel; Topal, Ahmet; Atamanalp, Muhammed
Eprinomectin (EPM), a member of avermectin family, is a semi-synthetic antibiotic. It has been known that avermectin family enters the aquatic environments and adversely affects the aquatic organisms. Effects of EPM is fully unknown in aquatic organisms especially fish, thus the aim of the present study was to investigate transcriptional changes (sod, cat, gpx) and activities of some antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) and malondialdehyde (MDA) levels, oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG)) and transcriptional changes of heat shock protein 70 (HSP70), and cytochromes P4501A (CYP1A) in liver tissues of rainbow trout exposed to sublethal EPM concentration (0.001 mu g/L, 0.002 mu g/L, 0.01 mu gL, 0.05 mu g/L) for 24 h, 48 h, 72 h and 96 h. The decrease in antioxidant enzyme (SOD, CAT and GPx) activity, transcriptional changes (sod, cat, gpx, HSP70 and CYP1A genes) and increase in MDA level and activity of 8-OHdG in a dose-time-dependent manner in the liver of rainbow trout were observed. The down-regulated of antioxidant (sod, cat and gpx), HSP70 and CYP1A obviously, the severity of which increased with the concentration of EPM and exposure time. The results imply that EPM could induce oxidative damage to the liver tissue of rainbow trout. The information presented in this study is helpful to understand the mechanism of veterinary pharmaceuticals-induced oxidative stress in fishes. (C) 2017 Elsevier Ltd. All rights reserved.
Investigation of 8-Ohdg, Cyp1a, Hsp70 and Transcriptional Analyses of Antioxidant Defence System in Liver Tissues of Rainbow Trout Exposed To Eprinomectin (Vol 65, Pg 136, 2017)
(Academic Press Ltd- Elsevier Science Ltd, 2018) Alak, Gonca; Yeltekin, Asli Cilingir; Tas, Ismail Hakki; Ucar, Arzu; Parlak, Veysel; Topal, Ahmet; Atamanalp, Muhammed
Magnetic Nanoparticles-Induced Neurotoxicity and Oxidative Stress in Brain of Rainbow Trout: Mitigation by Ulexite Through Modulation of Antioxidant, Anti-Inflammatory, and Antiapoptotic Activities
(Elsevier, 2022) Ucar, Arzu; Parlak, Veysel; Ozgeris, Fatma Betul; Yeltekin, Asli Cilingir; Arslan, Mehmet Enes; Alak, Gonca; Atamanalp, Muhammed
The prevalent exposition of metallic nanoparticles (MNPs) to the aquatic medium and their negative influence on human life is one of the major concerns global. Stress mechanization, as a non-specific and pervasive response, involves all physiological systems, particularly the closely interconnected neuroendocrine and immune systems. In this study, which was designed to obtain more data on the biological effects of ulexit, which prevents oxidative DNA damage by protecting against toxicity damage and offers new antioxidant roles. The concomitant use of ulexite (UX, as 18.75 mg/l) as a natural therapeutic agent against exposure to magnetic nanoparticles (Fe3O4-MNPs/0.013 ml/l) on Oncorhynchus mykiss was investigated for 96 h. The brain tissues were taken at the 48th and 96th hours of the trial period, the effects on neurotoxic, pro-inflammatory cytokine genes, antioxidant immune system, DNA and apoptosis mechanisms were analyzed. In the present study, it was determined that AChE activity and BDNF level in the brain tissue decreased over time in the Fe3O4-MNPs group compared to the control, and UX tried to depress this inhibition. While inhibition was determined in antioxidant system biomarkers (SOD, CAT, GPx, and GSH values), an induction was observed in lipid peroxidation indicators (MDA and MPO values) in Fe3O4-MNPs applied group. The same group data showed that TNF-alpha, IL-6, 8-OHdG and caspase-3 levels were increased, but Nrf-2 levels were decreased. The alterations in all biomarkers were found to be significant at the p < 0.05 level. In general, it was determined that Fe3O4-MNPs caused stress in O. mykiss and UX exhibited a positive effect on this stress management.
May Pdcu@f-Mwcnt Nps Be an Ecotoxicologic Risk
(Wiley, 2023) Alak, Gonca; Yeltekin, Asli Cilingir; Kokturk, Mine; Nas, Mehmet Salih; Parlak, Veysel; Calimli, Mehmet Harbi; Atamanalp, Muhammed
The mechanisms of various metal nanoparticles (NPs) are still a matter of debate in aquatic toxicology. In order to close this gap, the number of studies on this subject is increasing. The aims of this study are to explore the interactions of PdCu@f-MWCNT NPs with zebrafish and get to know if it has an ecotoxicological risk. In this study, we synthesized, characterized PdCu@f-MWCNT NPs, and investigated its ecotoxicological effects. The chemical and morphological structures of PdCu@f-MWCNT nanomaterials were elucidated with advanced analysis techniques such as scanning electron microscope (SEM), X-ray spectrophotometer (EDX), transmission electron microscope (TEM), and X-ray diffraction (XRD) analyses. The ecotoxicological risks were investigated by conducting biochemical analyses and malformation defects in zebrafish. The results were obtained using multiple marker applications including oxidative stress parameters, proinflammatory cytokine expressions, DNA damage, and apoptosis markers. The obtained findings showed embryonic development, survival rate, and incidence of malformation increasing in parallel with the dose increase in zebrafish exposed to PdCu@f-MWCNT NPs at 10-1000 mu g/L levels. Despite the observed decreases in antioxidant enzyme activities, GSH level, AChE activity, and NRF-2 level, inductions in malondialdehyde (MDA) level, IL-6, TNF-alpha, NF-kB, DNA damage, and apoptosis levels were observed with increasing dose. Considering these findings, it has been determined that there are toxic effects in zebrafish at all levels above the concentration that we examine as a safe dose (10 mu g/L). The effects of all studied concentrations of this NP above the safe dosage, especially on oxidative stress, malformation, and immune system, were found to be quite significant. The more widespread use of nanotechnology in the future will mean more contact of aquatic organisms with NPs. As a result, it is clearly seen that these organisms, which form the important link of the food chain, and the aquatic environment are living at risk conditions.
Neurophysiological Responses in the Brain Tissues of Rainbow Trout (Oncorhynchus Mykiss) Treated With Bio-Pesticide
(Taylor & Francis Ltd, 2019) Alak, Gonca; Ucar, Arzu; Yeltekin, Ash Cilingir; Parlak, Veysel; Nardemir, Gizem; Kizilkaya, Merve; Yanik, Telat
The aim of this study was to investigate neurophysiological responses in rainbow trout brain tissue exposed to natural/botanical pesticides. Fish were exposed to botanical and synthetic pesticides over a 21-day period. At the end of the treatment period, oxidative DNA damage (indicated by 8-OHdG (8-hydroxy-2'-deoxyguanosine), AChE activity (acetylcholinesterase) and transcriptional parameters (gpx (glutathione peroxidase), sod (superoxide dismutase), cat (catalase), HSP70 (heat shock protein 70) and CYP1A (cytochromes P450)) was investigated in control and application groups. Our results indicated that brain AChE activities decreased very significantly in fish treated with both insecticide types when compared with control (p < 0.05). 8-OHdG activity increased in a dose/time-dependent situation in the brain tissues of Oncorhynchus mykiss (p < 0.05). In addition, with regards to gene expression, gpx sod and, cat expressions were down-regulated, whereas CYP1A and HSP70 gene expression were up-regulated in fish treated with both insecticides when compared to the control group (p < 0.05). The data for this study suggests that bio-pesticides can cause neurophysiological changes in fish brain tissue.
Neuroprotective Effects of Dietary Borax in the Brain Tissue of Rainbow Trout (Oncorhynchus Mykiss) Exposed To Copper-Induced Toxicity
(Springer, 2018) Alak, Gonca; Ucar, Arzu; Yeltekin, Asli Cilingir; Comakli, Selim; Parlak, Veysel; Tas, Ismail Hakki; Turkez, Hasan
We aimed to investigate the modulating effects of dietary borax on the pathways in rainbow trout brain exposed to copper. For this aim, a comprehensive assessment was performed including biochemical (acetylcholinesterase (AChE), malondialdehyde (MDA), oxidative DNA damage (8-hydroxy-2-deoxyguanosine (8-OHdG), and caspase-3 levels) and transcriptional parameters (heat shock protein 70 (HSP70) and cytochromes P450 (CYP1A), glutathione peroxidase (gpx), superoxide dismutase (sod), and catalase (cat)) parameters and immunohistochemically staining of 8-OHdG. Special fish feed diets were prepared for the trial. These diets contained different concentrations of borax (1.25, 2.5, and 5mg/kg) and/or copper (500 and 1000mg/kg) at the period of pre- and co-treatment strategies for 21days. At the end of the treatment periods, brain tissue was sampled for each experimental group. As a result, the biochemical parameters were increased and AChE activity decreased in the copper and copper-combined groups in comparison with the control group and also with only borax applications (p<0.05). We observed an increase or decrease in particular biochemical parameters for the borax group in every application and we established that borax had protective effect against copper toxicity by decreasing and/or increasing the relevant biochemical parameters in brain tissue of fish. The biochemical results of borax and its combinations corresponded to the observations of gene expression data, which similarly concluded that HSP70 and CYP1A genes were strongly induced by copper (p<0.05). In addition, the expression levels of the sod, cat, and gpx genes in the fish brains exposed to borax and the borax combination groups were significantly higher than the only copper-treated groups. In conclusion, borax supplementation provided significant protection against copper-induced neurotoxicity in trout.
Neuroprotective Properties of Borax Against Aluminum Hydroxide-Induced Neurotoxicity: Possible Role of Nrf-2/Bdnf Pathways in Fish Brain
(Elsevier, 2023) Alak, Gonca; Turkez, Hasan; Ucar, Arzu; Yeltekin, Asli Cilingir; Ozgeris, Fatma Betul; Parlak, Veysel; Atamanalp, Muhammed
The current study was designed to assess the possible neuroprotective effect of borax (BX) against the toxicity of aluminum hydroxide [AH, Al (OH)3] on brain of rainbow trout (Oncorhynchus mykiss) with multibiomarker approaches. For this purpose, the presence of the neuroprotective action by BX against the AH exposure was assessed by the activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), myeloperoxidase (MPO), acetylcholinesterase (AChE). In addition, we evaluated glutathione (GSH), malondialdehyde (MDA), DNA damage (8-OHdG), apoptosis (caspase 3), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), nuclear factor erythroid-2 (Nrf-2), and brain-derived neurotrophic factor (BDNF) levels in 96 h semi-static treatment. In the 48th and 96th hour samplings, apoptosis induced by AH in the Nrf-2/BDNF/AChE pathways in rainbow trout brain tissue was revealed by DNA damage, enzyme inhibitions and lipid peroxidations. On the contrary applications of BX supported antioxidant capacity without leading apoptosis, lipid peroxidation, inflammatory response and DNA damage. BX also increased the BDNF levels and AChE activity. Moreover, BX exerted a neuroprotective effect against AH-induced neurotoxicity via down-regulating cytokine-related pathways, minimising DNA damage, apoptosis as well as up-regulating GSH, AChE, BDNF and antioxidant enzyme levels. It can be concluded that the combination of borax with AH modulated the toxic effects of AH.
Neurotoxic Responses in Brain Tissues of Rainbow Trout Exposed To Imidacloprid Pesticide: Assessment of 8-Hydroxy Activity, Oxidative Stress and Acetylcholinesterase Activity
(Pergamon-elsevier Science Ltd, 2017) Topal, Ahmet; Alak, Gonca; Ozkaraca, Mustafa; Yeltekin, Ash Cilingir; Comakli, Selim; Acil, Gurdal; Atamanalp, Muhammed
The extensive use of imidacloprid, a neonicotinoid insecticide, causes undesirable toxicity in non targeted organisms including fish in aquatic environments. We investigated neurotoxic responses by observing 8-hydroxy-2-deoxyguanosine (8-OHdG) activity, oxidative stress and acetylcholinesterase (AChE) activity in rainbow trout brain tissue after 21 days of imidacloprid exposure at levels of (5 mg/L, 10 mg/L, 20 mg/L). The obtained results indicated that 8-OHdG activity did not change in fish exposed to 5 mg/L of imidacloprid, but 10 mg/L and 20 mg/L of imidacloprid significantly increased 8-OHdG activity compared to the control (p < 0.05). An immunopositiv reaction to 8-OHdG was detected in brain tissues. The brain tissues indicated a significant increase in antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) compared to the control and there was a significant increase in malondialdehyde (MDA) levels (p < 0.05). High concentrations of imidacloprid caused a significant decrease in AChE enzyme activity (p < 0.05). These results suggested that imidacloprid can be neurotoxic to fish by promoting AChE inhibition, an increase in 8-OHdG activity and changes in oxidative stress parameters. Therefore, these data may reflect one of the molecular pathways that play a role in imidacloprid toxicity. (C) 2017 Elsevier Ltd. All rights reserved.
Neurotoxic Responses of Rainbow Trout (Oncorhynchus Mykiss) Exposed To Fipronil: Multi-Biomarker Approach To Illuminate the Mechanism in Brain
(Taylor & Francis Ltd, 2022) Ucar, Arzu; Ozgeris, Fatma Betul; Parlak, Veysel; Yeltekin, Asli Cilingir; Kocaman, Esat Mahmut; Alak, Gonca; Atamanalp, Muhammed
Insecticides have potential to non-target organisms, disrupting the healthy functioning of the aquatic environment as they are the ultimate receptor of the aquatic ecosystem. Insecticides, which are widely used in agriculture, have high neurotoxicity on aquatic organisms. In this study, the acute alterations [catalase (CAT), arylesterase (ARE), malondialdehyde (MDA), myeleperoxidase (MPO), paraoxonase (PON), glutathione peroxidase (GPX), superoxide dismutase (SOD), 8-hydroxy-2-deoxyguanosine (8-OHdG) level, caspase-3 activity, and Acetylcholinesterase (AChE) enzyme activity] caused by the different concentrations of Fipronil (FP) insecticide (0.05, 0.1, and 0.2 mg/L) on rainbow trout (Oncorhynchus mykiss) brain tissue were investigated. It has been determined that superoxide dismutase -catalase - glutathione peroxidase - paraoxonase and arylesterase enzyme activities were inhibited but MDA and MPO induced depending on the concentration in brain tissue. When compared with the control group, the changes between the pesticide exposed groups were found statistically significant (p < 0.05). In brain tissue, while AChE enzyme activity was decreased depending on concentration, caspase-3 activity increased with 8-OHdG level. As a result, it has been determined that FP is a dangerous environmental pollutant for aquatic organisms, even at low concentrations, inducing oxidative stress, damaging the brain tissue of fish and stimulating apoptosis.
Oxidative and Dna Damage Potential of Colemanite on Zebrafish: Brain, Liver and Blood
(Central Fisheries Research inst, 2020) Alak, Gonca; Parlak, Veysel; Ucar, Arzu; Yeltekin, Asli Cilingir; Ozgeris, Fatma Betul; Caglar, Ozge; Turkez, Hasan
Recently, boron has been used in animal feeding due to its significant biological roles. In this study, the action mechanism of colemanite (COL), a commercially important borate mineral, was aimed to investigate via evaluating parameters related to oxidative alterations on the brain, liver and blood tissues of zebrafish. For this purpose, zebrafish were exposed to different doses of COL (5, 10 and 20 mg/L) in a static test apparatus for 96 hours. Multiple biochemical analysis including determination of DNA damage (8-OHdG), apoptosis (Caspase-3), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), myeloperoxidase (MPO), paraoxonase (PON), arylesterase (AR) and lipid peroxidation (MDA) levels were performed in brain and liver tissues for assessing oxidative responses. In addition to micronucleus (MN) assay was performed in obtained blood tissues. The results indicated that low doses of COL supported antioxidant system and did not lead to oxidative stress in zebrafish brain and liver. Again, our results showed colemanite did not cause DNA damage or apoptosis at all tested concentrations. Besides the statistically insignificant changes (P>0.05) of MN rates of erythrocytes between the control and experimental groups revealed the non-genotoxic feature of COL on zebrafish. In conclusion, boron compounds especially COL can be used safely and provide positive impacts on aquatic environments.
The Protective Effect Exerted by Dietary Borax on Toxicity Metabolism in Rainbow Trout (Oncorhynchus Mykiss) Tissues
(Elsevier Science inc, 2019) Alak, Gonca; Parlak, Veysel; Yeltekin, Asli Cilingir; Ucar, Arzu; Comakli, Selim; Topal, Ahmet; Turkez, Hasan
The aim of this study was to evaluate the effectiveness of borax (BX) against heavy metal exposure on the transcriptional and biochemical reaction in vivo and alleviating effect on gill and liver tissues of rainbow trout. Due to this aim, fish were fed with different level of BX and/or copper (Cu) (1.25, 2.5 and 5 mg/kg of BX; 500 and 1000 mg/kg of Cu) for 21.days in pre- and co-treatment options. The transcriptional parameters [(heat-shock protein 70 (hsp70), and cytochromes P450 (cyp1a), glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT))], antioxidant enzyme activities (SOD, CAT and GPx), malondialdehyde (MDA), oxidative DNA damage (8-hydroxy-2'-deoxyguanosine (8-OHdG) and caspase-3 levels were investigated in different tissues samples of treated and control fish. Our results revealed that antioxidant enzyme activity was increased and levels of 8-OHdG, Caspase-3 and MDA were decreased in the BX and BX combined groups as compared to the copper combination group and to copper-only application during pre- and co-treatment (p < 0.05). Similarly, hsp70 and cyp1a gene expressions were decreased after treatment with BX. As conclusion, we suggest that borax itself is not an antioxidant it supportes antioxidant defense mechanism of fish disrupted by heavy metals.