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It is well known that cancer cells have an altered metabolism both to meet the energy needs and to provide initial molecules for the synthesis of macromolecules. To cope with the new metabolic state, different forms of certain enzymes are expressed in extreme amounts. These enzymes are seen as very attractive targets to deal with cancer. Pyruvate kinases isoenzyme M2 (PKM2) is a key enzyme that determines whether glucose is used for energy or synthesis of biosynthetic molecules. The dimeric form of PKM2 main form in several cancer cells serves the formation of synthetic precursors required for the cell growth and proliferation from glycolytic intermediates. Areas covered: This article reviews appropriate publications on PKM2 activators from the points of view of synthesis and biological activities between 2011-2017. Herein, based on the chemical structure, PKM2 activators are classified into sulfonamide, phenolic, carboxamide and pyridopyrimidinone derivatives. Expert opinion: PKM2 activation inhibits cell growth and proliferation by decreasing a number of biomolecules required for cell building. Therefore; PKM2 activators are considered as an ideal drug for or the treatment of many cancer pathogens. It is necessary to discover new, more active and selective compounds for PKM2 activation.

To date, sixteen CA isoenzymes found in humans belong to α-CA family, which differ in tissue distribution and subcellular localization 5, 6 . These isoenzymes provide carbon dioxide and ion transport, respiration, fluid balance and acid-base balance in many tissues 3 . They are also involved in biosynthetic reactions such as gluconeogenesis, lipogenesis, and urea synthesis as well as in many pathological and physiological events such as tumor formation and calcifica-Abstract: Recently, carbonic anhydrase (CA, E.C.4.2.1.1) inhibitors from natural product have paved the way for novel drug design in the treatment and prevention of some global diseases such as glaucoma, diabetes, and cancer. For this purpose, the inhibition effects of oleuropein and verbascoside from olive (Olea europaea L.) oil on human carbonic anhydrase I, and II (hCA I, and II) isoenzymes were evaluated in the current study. The inhibition effects of both natural compounds were determined by the esterase activity (in vitro). IC 50 value of oleuropein and verbascoside was calculated as 1.57 and 1.73 µM for hCA I isoenzyme, respectively. At the same manner, K i values were determined as 1.25 ± 0.42 and 2.00 ± 0.42 µM, respectively. Then, IC 50 value of each compound for hCA II isoenzyme was calculated as 2.23 and 1.90 µM, respectively. Similarly, K i values were determined as 2.37 ± 0.87 µM and 1.49 ± 0.33 µM, respectively. Also, the inhibitory effects and potent binding mechanisms of oleuropein and verbascoside on hCA I, and II isoenzymes were realized by molecular docking studies. Consequently, both natural phenolic compounds demonstrated the potent inhibition profiles against the both isoenzymes. Therefore, we believe that these results may break new ground in the drug development for the treatment of some global disorders.

Background:The aim of this study was to evaluate the antioxidant role of zinc (Zn) against radiation-induced cataract in the rat lens after total cranial irradiation with a single 5 Gray (Gy) dose of gamma irradiation.Materials and Methods:Twenty-one Sprague-Dawley rats were used for the experiment. The control group did not receive Zn or irradiation but received 1-ml saline orally plus sham-irradiation. The irradiation (IR) group received 5 Gy gamma irradiation to the total cranium as a single dose plus 0.1 ml physiological saline intraperitoneally. The IR plus Zn group received irradiation to total cranium plus 10 mg/kg/day Zn intraperitoneally. Biochemical parameters measured in rat lenses were carried out using spectrophotometric techniques.Results:Lens total (enzymatic plus non-enzymatic) superoxide scavenger activity (TSSA), glutathione reductase (GRD), and glutathione-S-transferase (GST) activities significantly increased in the IR plus Zn groups when compared with the IR group. However, TSSA, GRD and GST activities were significantly lower in the IR group when compared with the control group. Lens non-enzymatic superoxide scavenger activity (NSSA) in the IR plus Zn group was significantly increased compared to that of the IR group. Lens xanthine oxidase (XO) activity in the IR group significantly increased compared to that of both the control and IR plus Zn groups.Conclusion:Zn has clear antioxidant properties and prevented oxidative stress by scavenging free radicals generated by ionizing radiation in rat lenses.

This paper presents experimental and molecular docking studies on the inhibitory effects of tyrosol, hydroxytyrosol, luteolin, diosmetin, caffeic acid, luteolin 7-Oglycoside, and apigenin 7-O-glycoside from olive (Olea europaea L.) leaf against human carbonic anhydrase (hCA, E.C.4.2.1.1) isozymes I and II. After these isozymes were separately purified, their activities were determined using the esterase activity. IC 50 values for hCA I and II were calculated as 2.02-11.38 µM and 2.23-9.05 µM, respectively. The compounds were identified as CA inhibitors, with K i values in the ranges of 1.66-9.17 µM for the hCA I isozyme and 1.49-14.21 µM for hCA II. The inhibitory effects of these natural compounds were also compared to acetazolamide, which is a potent inhibitor of both CA isozymes. Our results may contribute to the synthesis of new CA inhibitors and pave the way for new drug design in the treatment of a number of diseases including cancer, obesity, diabetes, and glaucoma.