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    Evaluation of inhibition effects of some cardiovascular therapeutics on human erythrocyte carbonic anhydrase isoenzymes
    (2018) Kılınç, Namık; Alım, Zuhal; Şengül, Bülent; İşgör, Mehmet Mustafa; Beydemir, Şükrü
    Carbonic anhydrase enzyme plays a vital role in metabolic events such as acid-base regulation and respiration. In our research, it is tried to determine the inhibitory influences of the cardiovascular therapeutics esmolol hydrochloride, amiodarone hydrochloride and lidocaine hydrochloride on human erythrocytes carbonic anhydrases (hCA I and II). In accordance with this purpose, carbonic anhydrase isoenzymes were purified from human erythrocytes by using affinity chromatography method. Enzyme purity was checked by SDS-PAGE electrophoresis method. After the carbonic anhydrase enzymes were purified, the inhibitory affects of cardiovascular therapeutics on these enzymes, using esterase activity, which is the method of measuring in vitro activity, were examined. The three cardiovascular therapeutics dose-dependently decreased activity of hCAs. IC50 values of amiodarone hydrochloride, esmolol hydrochloride and lidocaine hydrochloride were found to be, respectively, 0.91 mM, 5 mM, 5.8 mM for hCA-I and 0.41 mM, 3.5 mM, and 6.36 mM for hCA-II. Our results proved that, under in vitro conditions, cardiovascular therapeutics significantly inhibit human CA-I and II activities. So, irregular use of these medicines may cause serious adverse effects in terms of human health.
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    Öğe
    Purification and characterization of nitric oxide synthase from bovine kidney and investigating drug-induced toxicities of some antibiotics on the enzyme activity
    (Bentham Science Publishers B.V., 2017) Işgör, Mehmet Mustafa; Ekinci, Deniz; Beydemir, Şükrü
    Introduction: Broad spectrums of antibiotics are widely used in the treatment of bacterial infections, particularly causing Staphylococcus aureus. These drugs have high acute renal injury (AKI) potency due to an increase in nitric oxide level. In this study, potency of nitric oxide synthase inhibition of some antibiotics was investigated according to vancomycin which was used as a reference antibiotic in renal injury. Methods and Results: Nitric oxide synthase (NOS) enzyme was purified by using 2'5'-ADP Sepharose 4B affinity chromatography from bovine kidney tissue in a single step with a yield of 3.58% and 1217-fold. Native and subunit molecular weights of the purified kidney NOS enzyme were calculated as 215 kDa and 114.8 kDa. Optimum pH, optimum ionic strength, optimum temperature and stable pH values for purified enzyme were determined as 7.5, 50 mM, 10°C and a pH range of 5.5-6.5, respectively. In vitro effects of antibiotics on purified enzyme activity were investigated by drawing Lineweaver-Burk plots. Enrofloxacin, kanamycin, chloramphenicol, gentamicin, vancomycin, cefazolin, streptomycin and ampicillin inhibited enzyme activity. IC50 values of these compounds were determined as 0.189 mM, 0.295 mM, 1.509 mM, 6.614 mM, 16.579 mM, 18.679 mM, 28.171 mM and 30.394 mM, respectively. Conclusion: Enrofloxacin and kanamycin were observed to have stronger NOS inhibitory effects as compared to vancomycin and may be more reliable antibiotics for use in renal infections as an alternative to vancomycin. © 2017 Bentham Science Publishers.