Biomimetic Chemical Catalysts in the Oxidative Activation of Drugs

ChemInform ◽  
2004 ◽  
Vol 35 (27) ◽  
Author(s):  
Jean Bernadou ◽  
Bernard Meunier
Keyword(s):  
Oxidative Activation

Oxidative activation of acylguanidine prodrugs: intestinal presystemic activation in rats limits absorption and can be inhibited by co-administration of ketoconazole

Xenobiotica ◽  
2003 ◽  
Vol 33 (1) ◽  
pp. 93-106 ◽  
Author(s):  
W. G. Humphreys ◽  
M. T. Obermeier ◽  
S. Chong ◽  
S. D. Kimball ◽  
J. Das ◽  
...  
Keyword(s):  
Oxidative Activation

scholarly journals Vitamin E isoforms directly bind PKCα and differentially regulate activation of PKCα

2011 ◽  
Vol 441 (1) ◽  
pp. 189-198 ◽  
Author(s):  
Christine A. McCary ◽  
Youngdae Yoon ◽  
Candace Panagabko ◽  
Wonhwa Cho ◽  
Jeffrey Atkinson ◽  
...  
Keyword(s):  
Vitamin E ◽  
Lipid Vesicles ◽  
C2 Domain ◽  
Binding Studies ◽  
Leucocyte Migration ◽  
Protein Kinase Cα ◽  
Oxidative Activation ◽  
Regulatory Effects ◽  
Opposing Effects

Vitamin E isoforms have opposing regulatory effects on leucocyte recruitment during inflammation. Furthermore, in vitro, vitamin E isoforms have opposing effects on leucocyte migration across endothelial cells by regulating VCAM (vascular cell-adhesion molecule)-1 activation of endothelial cell PKCα (protein kinase Cα). However, it is not known whether tocopherols directly regulate cofactor-dependent or oxidative activation of PKCα. We report in the present paper that cofactor-dependent activation of recombinant PKCα was increased by γ-tocopherol and was inhibited by α-tocopherol. Oxidative activation of PKCα was inhibited by α-tocopherol at a 10-fold lower concentration than γ-tocopherol. In binding studies, NBD (7-nitrobenz-2-oxa-1,3-diazole)-tagged α-tocopherol directly bound to full-length PKCα or the PKCα-C1a domain, but not PKCζ. NBD-tagged α-tocopherol binding to PKCα or the PKCα-C1a domain was blocked by diacylglycerol, α-tocopherol, γ-tocopherol and retinol, but not by cholesterol or PS (phosphatidylserine). Tocopherols enhanced PKCα-C2 domain binding to PS-containing lipid vesicles. In contrast, the PKCα-C2 domain did not bind to lipid vesicles containing tocopherol without PS. The PKCα-C1b domain did not bind to vesicles containing tocopherol and PS. In summary, α-tocopherol and γ-tocopherol bind the diacylglycerol-binding site on PKCα-C1a and can enhance PKCα-C2 binding to PS-containing vesicles. Thus the tocopherols can function as agonists or antagonists for differential regulation of PKCα.

scholarly journals Extracellularly oxidative activation and inactivation of matured prodrug for cryptic self-resistance in naphthyridinomycin biosynthesis

2018 ◽  
Vol 115 (44) ◽  
pp. 11232-11237 ◽  
Author(s):  
Yue Zhang ◽  
Wan-Hong Wen ◽  
Jin-Yue Pu ◽  
Man-Cheng Tang ◽  
Liwen Zhang ◽  
...  
Keyword(s):  
Assembly Line ◽  
Antibiotic Biosynthesis ◽  
Bond Functionalization ◽  
Gram Positive Bacteria ◽  
Self Defense ◽  
Clinical Resistance ◽  
Reactive Chemicals ◽  
Peptide Synthetase ◽  
Oxidative Activation ◽  
Temporal And Spatial

Understanding how antibiotic-producing bacteria deal with highly reactive chemicals will ultimately guide therapeutic strategies to combat the increasing clinical resistance crisis. Here, we uncovered a distinctive self-defense strategy featured by a secreted oxidoreductase NapU to perform extracellularly oxidative activation and conditionally overoxidative inactivation of a matured prodrug in naphthyridinomycin (NDM) biosynthesis from Streptomyces lusitanus NRRL 8034. It was suggested that formation of NDM first involves a nonribosomal peptide synthetase assembly line to generate a prodrug. After exclusion and prodrug maturation, we identified a pharmacophore-inactivated intermediate, which required reactivation by NapU via oxidative C-H bond functionalization extracellularly to afford NDM. Beyond that, NapU could further oxidatively inactivate the NDM pharmacophore to avoid self-cytotoxicity if they coexist longer than necessary. This discovery represents an amalgamation of sophisticatedly temporal and spatial shielding mode conferring self-resistance in antibiotic biosynthesis from Gram-positive bacteria.

scholarly journals Evidence for Oxidative Activation of c-Myc–Dependent Nuclear Signaling in Human Coronary Smooth Muscle Cells and in Early Lesions of Watanabe Heritable Hyperlipidemic Rabbits

Circulation ◽  
2000 ◽  
Vol 102 (17) ◽  
pp. 2111-2117 ◽  
Author(s):  
Filomena de Nigris ◽  
Tammam Youssef ◽  
SilviaAnna Ciafré ◽  
Flavia Franconi ◽  
Vittorio Anania ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Coronary Smooth Muscle ◽  
Nuclear Signaling ◽  
Early Lesions ◽  
Oxidative Activation

ChemInform Abstract: Electrophilic and Oxidative Activation of the Central C-C Bond in [3.3.n]Propellanes: A Theoretical Study.

ChemInform ◽  
2010 ◽  
Vol 30 (6) ◽  
pp. no-no
Author(s):  
A. A. FOKIN ◽  
P. R. SCHREINER ◽  
P. VON RAGUE SCHLEYER ◽  
P. A. GUNCHENKO
Keyword(s):  
Theoretical Study ◽  
Oxidative Activation
Sign in / Sign up

Export Citation Format

Share Document