Sürdürülebilir Kalkınma Amaçları

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• MakaleYalnız künye2016Scopus SJRQ2/r/bayburt/12391
  In vitro inhibitory effects of palonosetron hydrochloride, bevacizumab and cyclophosphamide on purified paraoxonase-I (hPON1) from human serum

  Türkeş, Cüneyt; Söyüt, Hakan; Beydemir, Şükrü

  In this study, we investigated the effects of the drugs, palonosetron hydrochloride, bevacizumab and cyclophosphamide, on human serum paraoxonase-I (hPON1) enzyme activity in in vitro conditions. The enzyme was purified ~231-fold with 34.2% yield by using ammonium sulphate precipitation, DEAE-Sephadex A-50 ion-exchange chromatography and Sephadex G-200 gel-filtration chromatography from human serum. hPON1 exhibited a single protein band on the SDS polyacrylamide gel electrophoresis. The inhibition studies were performed on paraoxonase activity of palonosetron hydrochloride, bevacizumab and cyclophosphamide. Ki constants were found as 0.033 ± 0.001, 0.054 ± 0.003 mM and 3.419 ± 0.518 mM, respectively. Compared to the inhibition rates of the drugs, palonosetron hydrochloride has the maximum inhibition rate. However, inhibition mechanisms of the drugs were determined as noncompetitive by Lineweaver-Burk curves.

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  AtıfScopus49·WoS49·OpenAlex56

  İncele
• MakaleAçık Erişim2015Scopus SJRQ2/r/bayburt/13905
  The toxicological impacts of some heavy metals on carbonic anhydrase from gilthead sea bream (Sparus aurata) gills

  Kaya, Elif Duygu; Söyüt, Hakan; Beydemir, Şükrü

  It is known that heavy metals have toxic effects on fish. Insufficient measures are a serious problem in our country and around the world. This problem can threaten human health in areas where it is common for people to obtain nutrition from local bodies of water. In this study, the toxicological impacts of some heavy metals were investigated on carbonic anhydrase activity in gilthead gills. Carbonic anhydrase (CA) was purified from gilthead sea bream (Sparus aurata) gills with a specific activity of 2872.92EUmg-1 and a yield of 32.84% using affinity chromatography. The overall purification was approximately ~84-fold. SDS-polyacrylamide gel electrophoresis showed a single band, and the MW was approximately 30.5kDa (Soyut et al., 2008, 2012; Soyut and Beydemir, 2008, 2012; Kaya et al., 2013). The kinetic and characteristic properties of CA such as the optimum pH, stable pH, optimum temperature, activation energy (Ea), activation enthalpy (δH), Q10, Km and Vmax were determined. Cadmium (Cd2+), copper (Cu2+), nickel (Ni2+) and silver (Ag+) inhibited CA activity in in vitro conditions. Ki values were calculated for these metals. Ki values were 31.20mM for cadmium (Cd2+), 161.96mM for copper (Cu2+), 10.79mM for nickel (Ni2+) and 0.0082mM for silver (Ag+) based on Lineweaver-Burk plots. Except for cadmium, heavy metals had the same inhibition mechanism. Cadmium was competitive, and the others were noncompetitive.

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  AtıfScopus17·WoS16·OpenAlex19

  İncele
• MakaleYayıncıda açık erişim2015Scopus SJRQ1/r/bayburt/13858
  Human serum paraoxonase-1 (hPON1): In vitro inhibition effects of moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium

  Türkeş, Cüneyt; Söyüt, Hakan; Beydemir, Şükrü

  In this study, we investigated the effects of antibacterial drugs (moxifloxacin hydrochloride, levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium) on human serum paraoxonase-1 (hPON1) enzyme activity from human serum in vitro conditions. For this purpose, hPON1 enzyme was purified from human serum using simple chromatographic methods. The antibacterial drugs exhibited inhibitory effects on hPON1 at low concentrations. Ki constants were calculated to be 2.641 ± 0.040 mM, 5.525 ± 0.817 mM, 35.092 ± 1.093 mM, 252.762 ± 5.749 mM and 499.244 ± 10.149 mM, respectively. The inhibition mechanism of moxifloxacin hydrochloride was competitive, whereas levofloxacin hemihidrate, cefepime hydrochloride, cefotaxime sodium and ceftizoxime sodium were noncompetitive inhibitors.

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  AtıfScopus53·WoS53·OpenAlex57

  İncele
• MakaleAçık Erişim2014Scopus SJRQ2/r/bayburt/13795
  Impact of antibacterial drugs on human serum paraoxonase-1 (hPON1) activity: An in vitro study

  Söyüt, Hakan; Kaya, Elif Duygu; Beydemir, Şükrü

  Objective: To investigate the in vitro effects of the antibacterial drugs, meropenem trihydrate, piperacillin sodium, and cefoperazone sodium, on the activity of human serum paraoxonase (hPON1). Methods: hPON1 was purified from human serum using simple chromatographic methods, including DEAE-Sephadex anion exchange and Sephadex G-200 gel filtration chromatography. Results: The three antibacterial drugs decreased in vitro hPON1 activity. Inhibition mechanisms meropenem trihydrate was noncompetitive while piperacillin sodium and cefoperazone sodium were competitive. Conclusions: Our results showed that antibacterial drugs significantly inhibit hPON1 activity, both in vitro, with rank order meropenem trihydrate piperacillin sodium cefoperazone sodium in vitro.

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  AtıfScopus5·OpenAlex7

  İncele
• MakaleAçık Erişim2014Scopus SJRQ2/r/bayburt/13724
  Effect of calcium channel blockers on paraoxonase-1 (PON1) activity and oxidative stress

  Türkeş, Cüneyt; Söyüt, Hakan; Beydemir, Şükrü

  Background: In this study, we investigated the in vitro effects of calcium channel blockers (nifedipine, nitrendipine, isradipine, and amlodipine besylate) on the activity of paraoxonase-1 (PON1). Methods: PON1 was purified from human serum using simple chromatographic methods, including DEAE-Sephadex anion-exchange and Sephadex G-200 gel filtration chromatography. Results: The calcium channel blockers decreased the in vitro PON1 activity. The inhibition mechanism of amlodipine besylate was noncompetitive, whereas nifedipine, nitrendipine, and isradipine were competitive inhibitors. Conclusions: Our results showed that calcium channel blockers exhibit inhibitory effects on PON1 at low concentrations. The IC50 values for nifedipine, nitrendipine, isradipine, and amlodipine besylate were determined to be 0.121 mM, 0.130 mM, 0.255 mM, and 0.304 mM, respectively, and the Ki constants were calculated to be 0.222 ± 0.049 mM, 0.151 ± 0.067 mM, 0.286 ± 0.137 mM, and 0.321 ± 0.002 mM, respectively.

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  AtıfScopus68·WoS67·OpenAlex74

  İncele
• MakaleAçık Erişim2013Scopus SJRQ2/r/bayburt/14154
  Carbonic anhydrase activity from the gilthead sea bream (Sparus aurata) liver: The toxicological effects of heavy metals

  Kaya, Elif Duygu; Söyüt, Hakan; Beydemir, Sukru

  Many studies have shown that metal ions may lead to oxidative stress in biological systems. Accordingly, DNA damage, protein modification, enzyme inhibition and activation, lipid peroxidation and many other effects may occur in living organisms. Many different formations of metal ions may enter human cells along with water, air, and various foods, and humans are negatively affected by these conditions, either directly or indirectly. These effects may cause irreversible damage to human metabolism. In this study, the toxicological effects of heavy metals on carbonic anhydrase enzyme activity from the gilthead sea bream liver were investigated. The carbonic anhydrase enzyme was purified via affinity chromatography and had a specific activity of 6775.5 EU mg(-1). The kinetics and characteristic properties, such as optimum pH, stable pH, optimum temperature, activation energy (E-a), activation enthalpy (Delta H), Q(10), K-m, and V-max, were determined for the purified enzyme SDS-polyacrylamide gel electrophoresis showed a single band and molecular weight of the subunit was approximately 25 kDa. Cd(II), Cu(II), Ni(II) and Ag(I) inhibited the enzyme activity in vitro. The type of inhibition and K-i values for these metals were calculated from Lineweaver-Burk plots as 17.74 mM, 36.20 mM, 12.85 mM and 0.025 mM for Cd(II), Cu(II), Ni(II) and Ag(I), respectively. All the metals were noncompetitive inhibitors. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.

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  AtıfWoS27·OpenAlex32

  İncele
• MakaleAçık Erişim2012Scopus SJRQ3/r/bayburt/14002
  Changes in carbonic anhydrase activity and gene expression of Hsp70 in rainbow trout (Oncorhynchus mykiss) muscle after exposure to some metals

  Söyüt, Hakan; Beydemir, Sükrü; Ceyhun, Saltuk Buǧrahan; Erdoǧan, Orhan; Kaya, Elif Duygu

  The effects of some heavy metals Co(II), Cu(II), Zn(II), and Ag(I) on carbonic anhydrase (CA) activity from rainbow trout (RT) muscle were investigated. Moreover, the effects of these metals on the expression of heat shock protein 70 (Hsp70) gene in muscle tissue were examined by real-time quantitative PCR (RT-PCR) in muscle tissue aft er exposure to the metals at the end of 6, 12, 24, and 48 h. CA was purified with a specific activity of 2300 EU mg-1, a yield of 19%, and 1080-fold. The molecular weights (Mw) of subunit and native enzyme were approximately 30 and 31 kDa, respectively. Optimum pH, stable pH, optimum temperature, activation energy (Eα), activation enthalpy (ΔH), and Q10 (the difference in activity of enzyme caused by the increment of 10 oC) value were determined. Apparent Michaelis constant (Km), maximum reaction rate (Vmax), and turnover rate of the enzyme (Kcat) values were 1.29 mM, 0.17 μmol min-1, and 28.8 s-1, respectively. The catalytic efficiency (Kcat/Km) was 22.3. The heavy metals decreased in vitro CA activity. Inhibition mechanisms of the metal ions were noncompetitive, except for the Co(II) ion, which was competitive. The expression of the Hsp70 gene was increased in the presence of the metal ions. The expression level at the end of 48 h was the highest for all of the metals. Consequently, the in vitro inhibition rank order was determined as Co(II) > Zn(II) > Cu(II) > Ag(I). Interestingly, Ag(I) was the most effective metal ion on Hsp70 gene expression.

  AtıfScopus9·WoS8·OpenAlex9

  İncele
• MakaleAçık Erişim2012Scopus SJRQ2/r/bayburt/13978
  The impact of heavy metals on the activity of carbonic anhydrase from rainbow trout (Oncorhynchus mykiss) kidney

  Söyüt, Hakan; Beydemir, Şükrü

  Many environmental and health problems have become a consequence of contamination of soil and water by toxic heavy metals and organic pollutants in the present age of technology. Heavy metals play vital roles in enzyme activities and other metabolic events with their bioaccumulative and nonbiodegradable properties among aquatic pollutants. Metal toxicity causes irregular metallothioneins protein synthesis, renal damage, and disruption of bone structure in humans and wildlife. In this study, we investigated in vitro effects of some metals on chemical-targeted carbonic anhydrase (CA) enzyme from rainbow trout kidney. The enzyme was purified with a specific activity of 17,285 EU × mg-1 and 31.7% yield and approximately 1800-fold using simple affinity purification method. Molecular weights of the subunit and native enzyme were estimated as 28.7 kDa and 26.9 kDa via sodium dodecyl sulfate polyacrylamide gel electrophoresis and Sephadex-G 200 column, respectively. Other kinetic properties of the enzyme were determined. Apparent Km, Vmax and kcat values were 0.40 mM, 0.097 μmol min-1 and 15.2 s-1 for p-nitrophenylacetate substrate, respectively. Inhibitory effects of cobalt, zinc, copper, cadmium and silver on CA activity were determined using the esterase method under in vitro conditions. IC50 and Ki values were calculated for metals. Ki values for Co2+, Zn2+, Cu2+, Cd2+ and Ag+ were 0.035, 1.2, 34.8, 103 and 257 from Lineweaver-Burk graphs, respectively. Consequently, in vitro inhibition rank order was determined as Co2+ > Zn2+ > Cu 2+ > Cd2+ > Ag+. The potential inhibitor for CA was found as Co2+ from these results.

  AtıfScopus17·WoS17·OpenAlex17

  İncele
• MakaleAçık Erişim2012Scopus SJRQ2/r/bayburt/13975
  Synthesis and carbonic anhydrase inhibitory properties of novel bromophenols including natural products

  Balaydiin, Halis Türker; Soyut, Hakan; Ekinci, Deniz; Göksu, Sleyman; Beydemir, Şkrü; Menzek, Abdullah; Şahin, Ertan

  (2-Bromo-3,4-dimethoxyphenyl) (3,4-dimethoxyphenyl)methanone (10) and its derivatives with Br, one dibromide and isomeric three tribromides, were synthesized. Demethylation of these compounds afforded a series of new bromophenols. Inhibition of human cytosolic carbonic anhydrase II (hCA II) isozyme by these new bromophenols and naturally occurring 3,4,6-tribromo-5-(2,5- dibromo-3,4-dihydroxybenzyl)benzene-1,2-diol (3), and 5,5′-methylenebis(3, 4,6-tribromo-benzene-1,2-diol) (4) was investigated. The synthesized compounds showed carbonic anhydrase inhibitory capacities with IC 50 values in the range of 0.7372 μM against hCA II. Some bromophenols investigated here showed effective hCA II inhibitory activity and might be used as leads for generating novel carbonic anhydrase inhibitors which are valuable drug candidates for the treatment of glaucoma, epilepsy, gastric and duodenal ulcers, neurological disorders, or osteoporosis.

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  AtıfScopus42·WoS43·OpenAlex41

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