Some Anticancer Agents Act on Human Serum Paraoxonase-1 to Reduce Its Activity

WOS: 000381035500003PubMed ID: 26873069Human serum paraoxonase (hPON1) is an important antioxidant enzyme. It protects low-density lipoproteins against oxidative stress and prevents atherosclerosis development. Anticancer agents have cardiotoxic effects, and this situation can lead to significant complications. Our aim was to evaluate the in vitro effects of some of the anticancer agents such as cetuximab, paclitaxel, etoposide, docetaxel, and ifosfamide on the activity of hPON1 in this study. For this reason, PON1 was purified from human serum with a specific activity of 3654.2 EU/mg and 16.84% yield using simple chromatographic methods. The five chemotherapeutic agents dose dependently decreased in vitro hPON1 activity. IC50 values for cetuximab, paclitaxel, etoposide, docetaxel, and ifosfamide were 0.0111, 0.042, 0.226, 0.665, and 23.3 mM, respectively. K-i constants were 0.0194, 0.0165, 0.131, 0.291, and 8.973 mM, respectively. The inhibition mechanisms of cetuximab, etoposide, docetaxel, and ifosfamide were non-competitive, and for paclitaxel was competitive. Consequently, inhibition of hPON1 by these anticancer agents may explain some of the cardiotoxic actions of these drugs

Purification and properties of glucose 6-phosphate dehydrogenase from turkey erythrocytes

62-65Glucose 6-phosphate dehydrogenase (G6PD) was purified from turkey erythrocytes by ammonium sulphate precipitation and followed by ADP Sepharose affinity gel chromatography. The yield was 49.71% and specific activity of the enzyme was found to be 44.16 EU/mg protein. By gel filtration the molecular mass was found to be 75 kDa. The enzyme had an optimum pH at 9.0, and optimum temperature at 50oC. Km and Vmax for NADP+ and glucose 6- phosphate (G6-P) as substrates were also determined and effects of inhibitors such as ATP, NADH and NADPH were examined

Inhibition behaviours of some phenolic acids on rat kidney aldose reductase enzyme: an in vitro study

WOS: 000392591100021PubMed ID: 28111996Aldose reductase (AR) inhibitors have vital importance in the treatment and prevention of diabetic complications. In this study, rat kidney AR was purified 19.34-fold with a yield of 3.49% and a specific activity of 0.88 U/mg using DE-52 Cellulose anion exchange chromatography, gel filtration chromatography and 2'5' ADP Sepharose-4B affinity chromatography, respectively. After purification, the in vitro inhibition effects of some phenolic acids (tannic acid, chlorogenic acid, sinapic acid, protocatechuic acid, 4-hydroxybenzoic acid, p-coumaric acid, ferulic acid, vanillic acid, syringic acid, alpha-resorcylic acid, 3-hydroxybenzoic acid and gallic acid) were investigated on purified enzyme. We determined IC50, K-i values and inhibition types of these phenolic acids. As a result, tannic and chlorogenic acid had a strong inhibition effect. On the other hand, gallic acid had a weak inhibition effect. In this study, all phenolic acids except for chlorogenic acid and p-coumaric acid showed non-competitive inhibition effects on rat kidney AR

Assessment of the inhibitory effects and molecular docking of some sulfonamides on human serum paraoxonase 1

WOS: 000412328200009Paraoxonase-1 (PON1) is an organophosphate hydrolyzer and antiatherogenic enzyme. Due to the PON1's crucial functions, inhibitors and activators of PON1 must be known for pharmacological applications. In this study, we investigated the in vitro effects of some sulfonamides compounds on human serum PON1 (hPON1). For this aim, we purified the hPON1 from human serum with high specific activity by using simple chromatographic methods, and after the purification processes, we investigated in vitro interactions between the enzyme and some sulfonamides (2-amino-5-methyl-1,3-benzenedisulfonamide, 2-chloro-4-sulfamoilaniline, 4-amino-3-methylbenzenesulfanilamide, sulfisoxazole, sulfisomidine, and 5-amino-2-methylbenzenesulfonamide). IC50, K-i values, and inhibition types were calculated for each sulfonamide. 2-amino-5-methyl-1,3-benzenedisulfonamide and 2-chloro-4-sulfamoilaniline exhibited noncompetitive inhibition effect, whereas 4-amino-3-methylbenzenesulfanilamide, sulfisoxazole, and sulfisomidine exhibited mixed type inhibition. On the other hand, 5-amino-2-methylbenzenesulfonamide showed competitive inhibition and so molecular docking studies were performed for this compound in order to assess the probable binding mechanism into the active site of hPON1

The synthesis of novel pyrazole-3,4-dicarboxamidesbearing 5-amino-1,3,4-thiadiazole-2-sulfonamide moiety with effective inhibitory activity against the isoforms of human cytosolic carbonic anhydrase I and II

WOS: 000387978400008PubMed ID: 27454619A series of 1-(3-substituted-phenyl)-5-phenyl-N-3,N-4-bis(5-sulfamoyl-1,3,4-thiadiazol-2-yl)-1H-pyrazole-3,4- dicarboxamides (4-15) were synthesized. The structures of these pyrazole-sulfonamides were confirmed by FT-IR, H-1 NMR, C-13 NMR and elemental analysis methods. Human cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isozymes (hCA I and II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of newly synthesized derivatives (4-15) were investigated in vitro on esterase activities of these isozymes. The K-i values were determined as 0.119-3.999 mu M for hCA I and 0.084-0.878 mu Mfor hCA II. The results showed that the compound 6 for hCA I and the compound 11 for hCA II had the highest inhibitory effect. Beside that, the compound 8 had the lowest inhibition effect on both isozymes. (C) 2016 Elsevier Inc. All rights reserved.Dumlupinar University Research FundDumlupinar University [2010/14]This work was supported by the Dumlupinar University Research Fund (Project Number: 2010/14). Also the authors are grateful to the Ataturk University Faculty of Sciences Department of Chemistry for providing the usage of spectroanalytic laboratory facilities and Dumlupinar University Faculty of Arts and Sciences Department of Physics for FT-IR measurements

Synthesis, biological evaluation and in silico studies of novel N-substituted phthalazine sulfonamide compounds as potent carbonic anhydrase and acetylcholinesterase inhibitors

The synthesis, characterization and biological evaluation of a series of novel N-substituted phthalazine sulfonamide (5a-1) are disclosed. Phthalazines which are nitrogen-containing heterocyclic compounds are biologically preferential scaffolds, endowed with versatile pharmacological activity, such as anti-inflammatory, cardiotonic vasorelaxant, anticonvulsant, antihypertensive, antibacterial, anti-cancer action. The compounds were investigated for the inhibition against the cytosolic hCA I, II and AChE. Most screened sulfonamides showed high potency in inhibiting hCA II, widely involved in glaucoma, epilepsy, edema, and other pathologies (K(i)s in the ranging from 6.32 +/- 0.06 to 128.93 +/- 23.11 nM). hCA I was inhibited with K(i)s in the range of 6.80 +/- 0.10-85.91 +/- 7.57 nM, whereas AChE in the range of 60.79 +/- 3.51-249.55 +/- 7.89 nM. ADME prediction study of the designed N-substituted phthalazine sulfonamides showed that they are not only with carbonic anhydrase and acetylcholinesterase inhibitory activities but also with appropriate pharmacokinetic, physicochemical parameters and drug-likeness properties. Also, in silico docking studies were investigated the binding modes of selected compounds, to hCA I, II, and AChE