Ataman Gönel

Dr. Ataman Gönel

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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Verified
Journal Article
Open access
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ETEbru TEMİZ
Ebru TEMİZ
IKIsmail Koyuncu
Ismail Koyuncu
MDMustafa DURGUN
Mustafa DURGUN
MCMurat CAGLAYAN
Murat CAGLAYAN
AGAtaman Gönel
Ataman Gönel
Claudiu SupuranClaudiu Supuran
Claudiu Supuran
Carbonic anhydrase IX (CAIX) is a hypoxia-related protein that plays a role in proliferation in solid tumours. However, how CAIX increases proliferation and metastasis in solid tumours is unclear. The objective of this study was to investigate how a synthetic CAIX inhibitor triggers apoptosis in the HeLa cell line. The intracellular effects of CAIX inhibition were determined with AO/EB, AnnexinV-PI, and γ-H2AX staining; measurements of intracellular pH (pHi), reactive oxygen species (ROS), and mitochondrial membrane potential (MMP); and analyses of cell cycle, apoptotic, and autophagic modulator gene expression (Bax, Bcl-2, caspase-3, caspase-8, caspase-9, caspase-12, Beclin, and LC3), caspase protein level (pro-caspase 3 and cleaved caspase-3, -8, -9), cleaved PARP activation, and CAIX protein level. Sulphonamide CAIX inhibitor E showed the lowest IC50 and the highest selectivity index in CAIX-positive HeLa cells. CAIX inhibition changed the morphology of HeLa cells and increased the ratio of apoptotic cells, dramatically disturbing the homeostasis of intracellular pHi, MMP and ROS levels. All these phenomena consequent to CA IX inhibition triggered apoptosis and autophagy in HeLa cells. Taken together, these results further endorse the previous findings that CAIX inhibitors represent an important therapeutic strategy, which is worth pursuing in different cancer types, considering that presently only one sulphonamide inhibitor, SLC-0111, has arrived in Phase Ib/II clinical trials as an antitumour/antimetastatic drug.

1 January 2018 in Journal of Enzyme Inhibition and Medicinal Chemistry
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Journal Article
Open access
IKIsmail Koyuncu
Ismail Koyuncu
AGAtaman Gönel
Ataman Gönel
AKAbdurrahim Kocyigit
Abdurrahim Kocyigit
ETEbru TEMİZ
Ebru TEMİZ
MDMustafa DURGUN
Mustafa DURGUN
Claudiu SupuranClaudiu Supuran
Claudiu Supuran
Selective inhibition with sulphonamides of carbonic anhydrase (CA) IX reduces cell proliferation and induces apoptosis in human cancer cells. The effect on CA IX expression of seven previously synthesised sulphonamide inhibitors, with high affinity for CA IX, as well as their effect on the proliferation/apoptosis of cancer/normal cell lines was investigated. Two normal and three human cancer cell lines were used. Treatment resulted in dose- and time-dependent inhibition of the growth of various cancer cell lines. One compound showed remarkably high toxicity towards CA IX-positive HeLa cells. The mechanisms of apoptosis induction were determined with Annexin-V and AO/EB staining, cleaved caspases (caspase-3, caspase-8, caspase-9) and cleaved PARP activation, reactive oxygen species production (ROS), mitochondrial membrane potential (MMP), intracellular pH (pHi), extracellular pH (pHe), lactate level and cell cycle analysis. The autophagy induction mechanisms were also investigated. The modulation of apoptotic and autophagic genes (Bax, Bcl-2, caspase-3, caspase-8, caspase-9, caspase-12, Beclin and LC3) was measured using real time PCR. The positive staining using γ-H2AX and AO/EB dye, showed increased cleaved caspase-3, caspase-8, caspase-9, increased ROS production, MMP and enhanced mRNA expression of apoptotic genes, suggesting that anticancer effects are also exerted through its apoptosis-inducing properties. Our results show that such sulphonamides might have the potential as new leads for detailed investigations against CA IX-positive cervical cancers.

19 May 2020 in Combinatorial Chemistry & High Throughput Screening
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EYEsra YAKIŞIK
Esra YAKIŞIK
UCUfuk Cakir
Ufuk Cakir
CTCuneyt Tayman
Cuneyt Tayman
TTTugba Taskin Turkmenoglu
Tugba Taskin Turkmenoglu
AGAtaman Gönel
Ataman Gönel
ITIşıl Ozkocak Turan
Işıl Ozkocak Turan
Background: Activated inflammation and oxidant stress during cerebral ischemia reperfusion injury (IRI) lead to brain damage. Astaxanthin (ASX) is a type of carotenoid with a strong antioxidant effect.Objective: The aim of this study was to investigate the role of ASX on brain IRI.Methods: A total of 42 adult male Sprague-Dawley rats were divided into 3 groups as control (n=14) group, IRI (n=14) group and IRI + ASX (n=14) group. Cerebral ischemia was instituted by occluding middle cerebral artery for 120 minutes and subsequently, reperfusion was performed for 48 hours. Oxidant parameter levels and protein degradation products were evaluated. Hippocampal and cortex cell apoptosis, neuronal cell count, neurological deficit score were evaluated.Results: In the IRI group, oxidant parameter levels and protein degradation products in the tissue were increased compared to control group. However, these values were significantly decreased in the IRI + ASX group (p<0.05). There was a significant decrease in hippocampal and cortex cell apoptosis and a significant increase in the number of neuronal cells in the IRI + ASX group compared to the IRI group alone (p<0.05). The neurological deficit score which was significantly lower in the IRI group compared to the control group was found to be significantly improved in the IRI + ASX group (p<0.05).Conclusion: Astaxanthin protects the brain from oxidative damage and reduces neuronal deficits due to IRI injury.

14 June 2019 in Medicina
Verified
Journal Article
Open access
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VAveysel ağan
veysel ağan
HCHakim Celik
Hakim Celik
MEMehmet Ali Eren
Mehmet Ali Eren
FAFatma Zehra Agan
Fatma Zehra Agan
ÖEÖzcan EREL
Özcan EREL
AGAtaman Gönel
Ataman Gönel
Background and objectives: The aim of this study was to research oxidative stress and thiol/disulphide homeostasis in Graves’ patients. Materials and Methods: The study included 33 Graves’ patients (research group) and 35 healthy subjects (control group). Serum oxidative stress and thiol/disulphide homeostasis (a new and automated spectrophotometric method developed by Erel and Neselioglu) parameters were studied and compared between the groups. Results: The native and total thiol levels and the native thiol/total thiol ratio were lower in patients with Graves’ disease compared to the control group (p < 0.001, p < 0.001, and p = 0.006, respectively). TOS (total antioxidant status), PC (protein carbonyl), OSI (Oxidative stress index), and disulphide/native thiol and disulphide/total thiol ratios were determined to be higher in the Graves’ disease group than in the control group (p < 0.001, p = 0.001, p = 0.001, p = 0.004, and p = 0.006, respectively). In the Graves’ disease group, the free triiodothyronine (FT3) and free thyroxine (FT4) levels were significantly positively correlated with impaired thiol/disulphide homeostasis and oxidative stress parameters (p < 0.05). Conclusion: The results of the current study demonstrated that oxidative stress and thiol/disulphide homeostasis increased towards disulphide formation due to thiol oxidation in Graves’ disease. In addition, a positive correlation of FT3 and FT4 was observed with oxidative stress parameters and impaired thiol/disulphide homeostasis.

29 June 2021 in Combinatorial Chemistry & High Throughput Screening
Verified
Journal Article
Closed access
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HAHasan Akduman
Hasan Akduman
CTCuneyt Tayman
Cuneyt Tayman
UCUfuk Cakir
Ufuk Cakir
EYEsra YAKIŞIK
Esra YAKIŞIK
DDDILEK DILLI
DILEK DILLI
AGAtaman Gönel
Ataman Gönel
Background/Aims: This study aimed to ascertain the effects of astaxanthin on the lungs of rat pups with bronchopulmonary dysplasia (BPD) induced by hyperoxia and lipopolysaccharide (LPS). Materials and Methods: Forty-two newborn Wistar rats, born to spontaneous pregnant rats, were divided into three groups: Hyperoxia (95% O2) + lipopolysaccharide (LPS) group, hyperoxia + LPS + astaxhantin group, and control: no treatment group (21% O2). Pups in the hyperoxia + LPS + astaxanthin group were given 100 mg/kg/day oral astaxanthin from the first day to the fifth day. Histopathologic and biochemical evaluations, including glutathione (GSH), total anti-oxidant status (TAS), total oxidant status (TOS), lipid hydroperoxide (LPO), 8-hydroxydeoxyguanosine (8-OHdG), advanced oxidation protein products (AOPP), myeloperoxidase (MPO), total thiol, tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), and caspase-3 activities, were performed. Results: Better survival rates and weight gain were demonstrated in the hyperoxia + LPS + astaxanthin group (p <0.001). In the histopathologic evaluation, the severity of lung damage was significantly reduced in the hyperoxia+LPS+astaxanthin group, as well as decreased apoptosis (ELİSA for caspase-3) (p <0.001). The biochemical analyses of lung tissues showed that TAS, GSH, and Total thiol levels were significantly higher in the astaxanthin treated group compared to the hyperoxia + LPS group (p <0.05) while TOS, AOPP, LPO, 8-OHdG, MPO levels were significantly lower (p <0.001). In addition, unlike the hyperoxia + LPS group, TNF-α and IL-1β levels in lung tissue were significantly lower in the astaxanthin-treated group (p <0.001). Conclusion: Astaxanthin was shown to reduce lung damage caused by inflammation and hyperoxia with its anti-inflammatory, anti-oxidant, anti-apoptotic properties, and to protect the lung from severe destruction.

25 December 2018 in Acta Clinica Belgica
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Journal Article
Closed access
AGAtaman Gönel
Ataman Gönel
Objectives: The purpose of this study is to investigate the elimination ratios of requested unnecessary tests and the cost-effectiveness to be achieved by means of 5 different algorithms with clinical validity defined in an artificial intelligence program. Methods: The clinician orders received from the hospital information management system were adapted to eliminate AST, direct bilirubin, chlorine, fPSA and fT3 tests using five different algorithms defined in the ALIN IQ software. Results: In this study, 18387 AST, 9500 direct bilirubin, 61 free PSA, 1127 FT3 and 11172 chlorine tests that were ordered within 45 days were eliminated using 5 different algorithms defined in the ALIN IQ software in the Laboratory of Harran University Faculty of Medicine. USD 5592.76 was saved in 45 days. The annual saving is expected to be 363710 tests and USD 45363.49. Conclusion: Five different tests were successfully eliminated with this study. Open-code smart softwares, which can create indefinite algorithms may be utilized as test eliminators in diagnostic clinical laboratories. Millions of dollars may be saved by means of such artificial intelligence softwares that can be adapted to any analyzer across the world.