Chinese Journal of Biochemistry and Molecular Biology. Protection of Mitochondria Against Oxidative Damage by the GPX Mimic 22TeCD

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1 ISSN CN ΠQ Chinese Journal of Biochemistry and Molecular Biology 18 (4) : TeCD 1,2),,,,,,, 3 2), (, ; 2), ) 22TeCD( ), ( GPX), GPX,22TeCD, GPX Ebselen 46 Fe 2 + ΠVc 22TeCD, 22 TeCD Ebselen,, Q554 Protection of Mitochondria Against Oxidative Damage by the GPX Mimic 22TeCD XUE Yan, REN Xiao2jun 1,2), ZHANG Kun,MU Ying, LIU Jun2qiu, CAO Peng, GUO Can2hui, LUO Gui2min 3, SHEN Jia2cong 2) ( Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education, Jilin University, Changchun , China ; 2) Key Laboratory for Supramolecular Structure & Materials of Ministry of Education, Jilin University, Changchun , China) Abstract A novel dicyclodextrinyl ditelluride (22TeCD) compound was devised to mimic GPX and its activity towards H 2 O 2 was found to be 4617 UΠ mol, which had activity 46 times more than ebselen, a well2studied GPX mimic Antioxidant activity was studied by using ferrous sulfateπascorbate2induced damage model system In order to determine the capacity for 22TeCD to antioxidize, the swelling, lipid peroxidation products and cytochrome c oxidase activity of were chosen as standards 22TeCD decreased the swelling of, inhibited the lipid peroxidation, retained the activity of cytochrome2c oxidase and ex2 hibited great antioxidant ability in comparison with ebselen Key words GPX mimic,, anti2oxidation, tellurium (ROS), [,ROS,ROS DNA,, ROS : : ( G ) (No ) 3 Tel : ( ,E2mail jlu edu cn,, , Received :October 12,2001 ;Accepted :December 24,2001 Supported by the Major State Basic Research Development Program ( No, [1, ] G ) and the National Natural Science Foundation of China (No ) 3 Correspoding author Tel : ( E2mail jlu edu cn ( E )

2 4 : 22TeCD 507 ( GPX) ] ( GPX) Wilson,, 015 ml, 50 mmolπl ph 710,1 mmolπl EDTA,1 mmolπl,1 mmolπl, [2 ] GPX, 0125 mmolπl NADPH,1 U, 20 80,,37 10 min, GPX,, 015 mmolπl 340 nm NADPH, ( ) GPX H 2 O Ebselen, (U) 1 molπl [3 ] : NADPH GPX 11213, [4 ], molπl,10 mmolπl EDTA GPX 25 mmolπl HEPES2NaOH, ph 714, 22TeCD, GPX 3800 rπmin (10 # ) 20 min, Ebselen 46 22TeCD Ebselen 22TeCD, rπmin (16125 # ) Ebselen 15 min, NMR 13 C2NMR IR UV XPS (Sigma ),, (015 mgπml),1 molπl GSH, GPX ( ) c ( ph 714, 37 ) ( Fluka ) ( 015 mmolπl Vc 1215 molπl FeSO 4 ) ( ),,,, ( ), MDA( ),CCO( ) GS (, ),UV2120 ( ),UV2 Vc FeSO ( ),J [7 ] (Beckman ), HZQ2X100, 520 nm ( ), Hettich MIKRO22R) TeCD 2[ 22 2( MDA, ) ] 2CD (22OTs2 2CD) [5 ] 1127 g Te 019 g NaBH 4 20 ml, N 2 MDA,MDA 1 h Te, (TBA), ml, NaHTe 2 g 22OTs2 2CD nm mol L ml 50 mmolπl ph 710 cm - 1 MDA [8 ], 5 ml NaHTe N h :1 ml 1 ml 700 gπl TCA,1 ml 5gΠL,, TBA ;80 40 min, rπmin 10 Sephadex G225, 1 min 532 nm [6 ], rπmin (16125 # ) 15 min [9 ] Fe 2 + ΠVc molπl KCl,1 mmolπl MgCl 2,5 mmolπl, 60 % 1 H (CCO)

3 g 2 min,4, 125 mmolπl KCl,1 mmolπl MgCl 2 5 mmolπl 10 mmolπl ph 714, 22TeCD 100 mmolπl ph 710,, 22TeCD CCO [9 ] CCO 2 ml, 22TeCD Ebselen c 15 molπl, Fig12, 22TeCD Ebselen 25, 5 l 10 mmolπl K 3 Fe (CN) 6, ROS H 2 O 2 c, CCO, 550 nm TeCD c Fig13 22TeCD, K 3 Fe (CN) 6, MDA, 22TeCD,MDA ; 22TeCD A ln ( A t - A )2t,,MDA 22 ( K app ) c, TeCD 16 molπl, 50 min,mda CCO : K app Πmg TeCD GPX 22TeCD Ebselen H 2 O 2 GPX, Table 1, Table 1 Comparison between GPX activities of 22TeCD and Ebselen GPX mimic Substrate GPX activityπu mol - 1 Ebselen H 2 O [6 ] 22TeCD H 2 O GPX Fig11 Fe 2 + ΠVc, 22TeCD ; 520 nm, Fig 2 Effect of the different GPX mimics on the swelling of ( ) control ; ( ) damage + 8 molπl of 22TeCD ; ( ) damage + 8 molπl of Ebselen ; ( g ) damage Fig 1 Effect of concentration of 22TeCD on the swelling of ( ) control ; ( ) damage + 16 molπl of 22TeCD ; ( ) damage + 8 molπl of 22TeCD ; ( ) damage + 2 molπl of 22TeCD ; ( g ) damage Fig 3 Dependence of extent of MDA accumulation on concentration of 22TeCD ( ) damage ; ( ) damage + 2 molπl of 22TeCD ; ( ) damage + 8 molπl of 22TeCD ; ( g ) damage + 16 molπl of 22TeCD

4 4 : 22TeCD %, 6412 % MDA 3 Fig14 22TeCD MDA Ebselen TeCD CCO CCO,ROS,, ROS, Fig15,Fe 2 + ΠVc ROS CCO 60 min CCO 59 %, 8 molπl 22TeCD CCO 60 min 88 % Fe 2 + ΠVc,60 min, 8 molπl Ebselen, CCO 71 % Ascorbic acid + O 2 Dehydroascorbic acid + H 2 O 2 22TeCD Ebselen GPX Fig 4 Effect of different GPX mimics on the accumulation of MDA ( ) damage ; ( g ) damage + 8 molπl of 22TeCD ; ( ) damage + 8 molπl of Ebselen Absorbance values represent MDA and are means of three determinations Fig 5 Effect of different GPX mimics on CCO activity in damaged Activity of CCO in the control is defined as 100 % ( ) damage + 8 molπl of 22TeCD ; ( ) damage + 8 molπl of Ebselen ; ( g ) dam2 age Values are means from three sets of experiments ROS, [10 ] ROS, : ( Fe ( ) + biopolymer biopolymer2fe ( ) (2) Biopolymer2Fe ( ) + O - 2 Biopolymer2Fe ( ) + O 2 Bioplymer2Fe ( ) + H 2 O 2 (3) Biopolymer2Fe ( ) + OH + OH - (4) Ascorbic acid + 2Fe 3+ Dehydroascorbic acid + 2Fe H + (5),Fe 2 +, Fe 2 + [11 ] Fenton, H 2 O 2 Vc ( ) Vc ( ) GPX GPX Fe 2 + ΠVc MDA CCO,22TeCD, MDA 22TeCD, MDA, 22TeCD GPX 22TeCD Eb2 selen 50, Ebselen,22TeCD GPX, : Fe 2 + ΠVc, 22TeCD GPX

5 510 18,22TeCD, 104 ( References) 1 Spector A Oxidative stress induced cataract : mechanism of action FAS EB J, 1995, 9 : Floh L The Selenoprotein Glutathione Peroxidase In : Dolphin D, Poulsin R, Avramovic O eds Glutathione : Chemical, Biochemical, Medical Aspects New York : John Wiley & Sons, 1989 : Sies H Ebselen, a selenoorganic compound as glutathione peroxidase mimic Free Radic Biol Med, 1993, 14 : Breslow R, Dong S D Biomimetic reactions catalyzed by cyclodextrins and their derivatives Chem Rev, 1998, 98 : ,,,,, 22 2 (Liu 11 Samuni A,Aronovitch J,Godinger D,Chevion M,Czapski G On the cy2 Jun2qiu, Gao Shu2juan, Luo Gui2min, Yan Gang2lin, Jiang Ming2 shou, Shen Jia2cong Synthesis and catalytic properties of 22selenium bridged 2cyclodextrin Chin J Biochem Mol Biol), 1999,15 ( :102 6 Wilson S R, Zucker P A, Huang R C, Spector A Development of syn2 thetic compounds with glutathione peroxidase activity J Am Chem Soc, 1989, 111 : Harman L S, Carver D K, Schreiber J, Mason R P Oxidation of gluta2 thione to its thiyl free radical metabolite by prostaglandin H synthase A potential endogenous substrate for the hydroperoxidase J Biol Chem, 1986, 261 : Pryor W A,Stanley J P,Blair E Lipids, 1976,11 : Epp O, Ladenstein R, Wendel A The refined structure of the sele2 noenzyme glutathione peroxidase at 0122nm resolution Eur J Biochem, 1983, 133 : Hunter F E, Scott J A, Hoffsten P E, Guerra F, Weinstein J, Schnei2 der A, Schutz B, Fink J, Ford L, Smith E Studies on the mechanism of ascorbate2induced swelling and lysis of isolated liver J Boil Chem, 1964, 239 : totoxicity of vitamin C and metal ions Eur J Biochem, 1983, 137 :