Rapid Inactivation of Prostaglandin Endoperoxide Synthases by N-(Carboxyalkyl)maleimides

Kalgutkar, Amit S.; Marnett, Lawrence J.

doi:10.1021/bi00195a002

Cited by 13 publications

(14 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have recently shown that maleimide derivatives tethered to a series of medium-length fatty acids exhibit much more potent cyclooxygenase inactivation. The most potent of these inhibitors, N -(carboxyheptyl)maleimide, inhibits enyzme activity within seconds after mixing with a stoichiometric amount of PGHS protein …”

Section: Introductionmentioning

confidence: 99%

“…The most potent of these inhibitors, N-(carboxyheptyl)maleimide, inhibits enyzme activity within seconds after mixing with a stoichiometric amount of PGHS protein. 13 The lack of PGHS inhibition by the N-(carboxyheptyl)succinimide suggests that this rapid inhibition results from covalent modification of the protein. Varying the length of the alkyl chain in N-(carboxyalkyl)maleimides alters their potency as rapid inhibitors but does not significantly affect their ability to inhibit the enzyme on prolonged incubation (∼30 min).…”

Section: Introductionmentioning

confidence: 99%

“…The mechanism of inhibition of PGHS-1 by N-(carboxyheptyl)maleimide was investigated. Incubation of apoPGHS-1 with 2 equiv of N-(carboxyheptyl) [3,[4][5][6][7][8][9][10][11][12][13][14] C]maleimide led to the incorporation of radioactivity in the protein, but no adduct was detected by reversedphase HPLC, suggesting that it was unstable to the chromatographic conditions. Furthermore, hematin-reconstituted PGHS-1, which was rapidly inhibited by N-(carboxyheptyl)maleimide, displayed spontaneous regeneration of about 50% of the cyclooxygenase and peroxidase activities, suggesting that the adduct responsible for the inhibition breaks down to regenerate active enzyme.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Design, Synthesis, and Biochemical Evaluation ofN-Substituted Maleimides as Inhibitors of Prostaglandin Endoperoxide Synthases

1996

Self Cite

View full text Add to dashboard Cite

N-(Carboxyalkyl)maleimides are rapid as well as time-dependent inhibitors of prostaglandin endoperoxide synthase (PGHS). The corresponding N-alkylmaleimides were only time-dependent inactivators of PGHS, suggesting that the carboxylate is critical for rapid inhibition. Several N-substituted maleimide analogs containing structural features similar to those of the nonsteroidal anti-inflammatory drug aspirin were synthesized and evaluated as inhibitors of PGHS. Most of the aspirin-like maleimides inactivated the cyclooxygenase activity of purified ovine PGHS-1 in a time- and concentration-dependent manner similar to that of aspirin. The peroxidase activity of PGHS was also inactivated by the maleimide analogs. The cyclooxygenase activity of the inducible isozyme, i.e., PGHS-2, was also inhibited by these compounds. The corresponding succinimide analog of N-5-maleimido-2-acetoxy-1-benzoic acid did not inhibit either enzyme activity, suggesting that inactivation was due to covalent modification of the protein. The mechanism of inhibition of PGHS-1 by N-(carboxyheptyl)maleimide was investigated. Incubation of apoPGHS-1 with 2 equiv of N-(carboxyheptyl)[3,4-14C]maleimide led to the incorporation of radioactivity in the protein, but no adduct was detected by reversed-phase HPLC, suggesting that it was unstable to the chromatographic conditions. Furthermore, hematin-reconstituted PGHS-1, which was rapidly inhibited by N-(carboxyheptyl)maleimide, displayed spontaneous regeneration of about 50% of the cyclooxygenase and peroxidase activities, suggesting that the adduct responsible for the inhibition breaks down to regenerate active enzyme. ApoPGHS-1, inhibited by N-(carboxyheptyl)maleimide, did not display regeneration of enzyme activity, but addition of hematin to the inhibited apoenzyme led to spontaneous recovery of about 50% of cyclooxygenase activity. These results suggest that addition of heme leads to a conformational change in the protein which increases the susceptibility of the adduct toward hydrolytic cleavage. ApoPGHS-1, pretreated with N-(carboxyheptyl)maleimide, was resistant to trypsin cleavage, suggesting that the carboxylate functionality of the maleimide binds in the cyclooxygenase channel. A model for the interaction of N-(carboxyheptyl)maleimide in the cyclooxygenase active site is proposed.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Design, Synthesis, and Biochemical Evaluation ofN-Substituted Maleimides as Inhibitors of Prostaglandin Endoperoxide Synthases

1996

Self Cite

View full text Add to dashboard Cite

show abstract

“…This suggested that the products were GSH-IP (Marnett et al, 1983), were used as a source of PGS. The peroxidase activity in the RSV microsomes was determined to be 5.4 mol/min/mg protein, using guaiacol as a substrate as described previously (Kalgutkar and Marnett, 1994). RSV microsomal incubations of 5-OHTBZ were fortified with reduced GSH (or GSH-IP) and initiated with either arachidonic acid or H 2 O 2 (to bypass the cyclooxygenase step of PGS).…”

Section: Formation Of Gsh Conjugate Of 5-ohtbz (M3) By Hrp Lc-ms/msmentioning

confidence: 99%

In Vitro Metabolic Activation of Thiabendazole via 5-Hydroxythiabendazole: Identification of a Glutathione Conjugate of 5-Hydroxythiabendazole

Dalvie¹,

Smith²,

Deese³

et al. 2006

Drug Metab Dispos

View full text Add to dashboard Cite

Thiabendazole (TBZ) (Fig. 1) is a broad-spectrum antihelmintic used for treatment of parasitic infections in animals and humans and an agricultural fungicide for postharvest treatment of fruits and vegetables (Walton et al., 1999;Groten et al., 2000). It is recognized as a potent nephrotoxin that causes tubular necrosis, leading to severe kidney damage and a teratogen that results in impairment of mouse limb development and selective toxicity to the embryo (Ogata et al., 1984;Mizutani et al., 1990;Tada et al., 1992;Fujitani et al., 1999). Irreversible binding of TBZ-related radioactivity to macromolecules and tissue protein in the mouse embryo has also been observed after oral dosing of [ 14 C]TBZ to pregnant mice (Yoneyama and Ichikawa, 1986). In humans, several isolated cases of hepatotoxicity, such as intrahepatic cholestasis or micronodular cirrhosis, have also been reported after TBZ administration (Manivel et al., 1987;Bion et al., 1995). It is currently believed that TBZ-induced nephrotoxicity is a result of P450-dependent oxidative cleavage of the thiazole moiety in TBZ to a proximate toxicant, thioformamide ( Fig. 1) (Mizutani et al., 1994). However, the mechanisms responsible for TBZ-induced hepatotoxicity in humans and teratogenicity in preclinical species are not clear.TBZ is extensively metabolized in animals and humans (Tocco et al., 1966). The primary route of metabolism is the CYP1A2-catalyzed formation of 5-hydroxythiabendazole (5-OHTBZ), which is further converted to a glucuronide and a sulfate conjugate and is eliminated in the urine and bile (Wilson et al., 1973;Rey-Grobellet et al., 1996; Coulet et al., 1998a,b). Other metabolites such as 4-hydroxythiabendazole, 2-acetylbenzimidazole, N-methylthiabendazole, and benzimidazole have also been detected (Fujitani et al., 1991). Recent studies by Coulet et al. (2000) have shown good correlation in the covalent binding of the radiolabel to proteins and the formation of 5-OHTBZ in incubations of [ 14 C]TBZ with cultured human and rabbit hepatocytes. These studies have also shown that treatment of CYP1A2-expressing liver cells with isolated [14 C]5-OHTBZ leads to significant covalent binding of the radiolabel (Coulet et al., 2000). Furthermore, 5-OHTBZ has been described to possess the same teratogenic potential as the parent drug TBZ, as demonstrated in a limb-bud culture system (Tsuchiya et al., 1987

show abstract

“…In recent years, aspirin was found to reduce the risk of heart attack and stroke. Aspirin is also suggested to be effective against colorectal cancer, although it has no effect on other types of cancers such as lung, breast, ovary, testis, lymphoma, and leukemia. − The exact mechanism by which aspirin exerts its antitumor activity is not clear. However, NSAID drugs are found to block the synthesis of prostaglandins long chain fatty acid compounds that have various functions, including stimulation of cell proliferation and suppression of immune reaction, both of which are linked to tumor progression.…”

Section: Introductionmentioning

confidence: 99%

RNA−Aspirin Interaction Studied by FTIR Difference Spectroscopy

Neault

Tajmir-Riahi

1997

J. Phys. Chem. B

View full text Add to dashboard Cite

Aspirin is an old drug, which belongs to the nonsteroidal anti-inflammatory drugs. It is used extensively as a painkiller, and recently, it has been suggested to be effective against colorectal cancer. The aim of this study is to investigate the interaction of yeast RNA with aspirin in aqueous solution at physiological pH with drug/RNA(P) (P=phosphate) molar ratios of r = 1/80, 1/40, 1/20, 1/10, 1/4, 1/2, and 1. Fourier transform infrared (FTIR) difference spectroscopy is used to determine drug binding mode, sequence selectivity, and RNA secondary structure, as well as the structural variations of the aspirin−RNA complexes in aqueous solution. Spectroscopic evidence showed that at low drug concentration (r = 1/80), aspirin−RNA interaction is through the G-C and A-U base pairs and the backbone PO2 group. Such interaction largely perturbs the G-C vibrations at 1698 and 1488 cm-1 and the A-U bands at 1654 and 1608 cm-1 as well as the phosphate antisymmetric stretch at 1244 cm-1. At r = 1/40, minor structural changes occur for the ribose−phosphate backbone geometry with RNA remaining in the A-conformation. At r > 1/20, a partial helix destabilization occurs. The drug distributions around the double helix are about 50% G-C, 30% A-U, and 20% PO2 groups. A comparison between aspirin−RNA and asprin−DNA complexes shows minor differences. The aspirin anion binding is via drug OCO and COOCH3 groups.

show abstract

Rapid Inactivation of Prostaglandin Endoperoxide Synthases by N-(Carboxyalkyl)maleimides

Cited by 13 publications

References 19 publications

Design, Synthesis, and Biochemical Evaluation ofN-Substituted Maleimides as Inhibitors of Prostaglandin Endoperoxide Synthases

Design, Synthesis, and Biochemical Evaluation ofN-Substituted Maleimides as Inhibitors of Prostaglandin Endoperoxide Synthases

In Vitro Metabolic Activation of Thiabendazole via 5-Hydroxythiabendazole: Identification of a Glutathione Conjugate of 5-Hydroxythiabendazole

RNA−Aspirin Interaction Studied by FTIR Difference Spectroscopy

Contact Info

Product

Resources

About