Mechanism of the inhibition of mutagenicity of a benzo[a]pyrene 7,8-diol 9,10-epoxide by riboflavin 5'-phosphate.

Wood, Alexander W.; Sayer, Jane M.; Newmark, Harold L.; Yagi, Haruhiko; Michaud, Dennis P.; Jerina, Donald M.; Conney, Allan H.

doi:10.1073/pnas.79.17.5122

Cited by 38 publications

(12 citation statements)

References 26 publications

(39 reference statements)

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“…There are some early investigations of the hetero-association of the riboflavin vitamins (RBF or FMN) with other aromatic compounds: the complexation of RBF/FMN with a series of betacarbolines, indoles [171][172][173][174][175], simple hydrocarbons [176][177][178][179][180] and some antibiotics [129,130]. The formation of 1:1 stacked complexes of aromatic molecules was reported, where an increase in stability and lowering of entropy was related to the increase in aromaticity of the drug chromophore in RBF-drug complexes for a series of betacarbolines and some other hydrocarbons [171].…”

Section: Drug-vitamin Systemmentioning

confidence: 99%

Hetero-association of aromatic molecules in aqueous solution

Evstigneev

2014

International Reviews in Physical Chemistry

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Knowledge of the physical chemistry of small molecules complexation (the hetero-association) in aqueous solution is increasingly important in view of the rapidly emerging branch of supramolecular chemistry dealing with the formation of heterogeneous polymeric structures having specific functional roles. In this paper, the 50-year history of scientific studies of hetero-association of heterocyclic aromatic molecules in aqueous solution has been reviewed. Some important correlations of structural and thermodynamic parameters of complexation have been reported based on large data-set of hetero-association parameters accumulated to date. The fundamental problem of 'energetic composition' of π-stacking is extensively discussed. The review has shown that there are some gaps in our understanding of heteroassociation, which provides a challenge for further studies in this area.

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Section: Drug-vitamin Systemmentioning

confidence: 99%

Hetero-association of aromatic molecules in aqueous solution

Evstigneev

2014

International Reviews in Physical Chemistry

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“…Cycloheximide being an inhibitor of general protein synthesis inhibits the BaP-mediated induction of AHH and thus lowers the effective level of the enzyme in the cell. Flavin mononucleotide inhibits the interaction of the metabolite with nucleic acids (22,23).…”

Section: Covalent Interaction Of [3h]bap With Cytoplasmic and Nuclearmentioning

confidence: 99%

Mechanism of benzo(a)pyrene induction of alpha-human chorionic gonadotropin gene expression in human lung tumor cells.

Wong¹,

Biswas²

1985

The Journal of Cell Biology

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Human lung cells (ChaGo) derived from a bronchogenic carcinoma synthesize and secrete in the culture medium the alpha subunit of the glycoprotein hormone, human chorionic gonadotropin (alpha-hCG). The synthesis of alpha-hCG by ChaGo cells could be further stimulated by treatment with sublethal concentrations of the polycyclic aromatic hydrocarbons (PAHs), benzo(a)pyrene (gaP), or dimethylbenzanthracene. The production of alpha-hCG could be correlated to the levels of alpha-hCG-specific mRNA sequences in control and PAH-treated cells. Further analysis of the RNA species (Northern blot) revealed that the level of the mature (~1.0 kb) and the high molecular weight alpha-hCG specific nuclear RNA sequences (~2.2 and 5 kb) were all greater in PAH-treated cells.Addition of [3H]BaP (0.25 #g/ml) in the culture medium of ChaGo cells led to immediate uptake of the radioactive compound apparently by simple diffusion. SDS PAGE and subsequent fluorography revealed that the radioactive compound interacted and formed covalent complexes with cytoplasmic and nuclear proteins. This covalent interaction of the [3H]BaP molecule with cellular proteins could be significantly inhibited by either inhibiting the activity of the enzyme aryl hydrocarbon hydroxylase with 7,8-benzoflavone or by reducing the cellular concentration of the enzyme by simultaneous incubation with cycloheximide. These results suggested that in ChaGo cells, the observed covalent complexes were formed by the interaction of the BaP metabolites with cellular proteins. The concentrations at which 7,8-benzoflavone or cycloheximide inhibited (a) formation of metabolites from [3H]BaP and (b) their covalent interaction with cell protein did not affect the BaP-induced stimulation of alphahCG gene expression. However, the cytotoxic effects of BaP in ChaGo cells seemed to be exerted by the metabolism of the compounds. Results presented in this report suggest that gap metabolism and the interaction of the metabolites with cell proteins were not essential for the BaP-induced modulation of alpha-hCG gene expression.Polycyclic aromatic hydrocarbons (PAHs) ~ are currently recognized as one of the major classes of environmental carcinogenic pollutants (1). Of the PAHs, benzo(a)pyrene (BaP) is Abbreviations used in this paper: AHH, aryl hydrocarbon hydroxylase; BaP benzo(a)pyrene; BF, 7,3-benzoflavone; ChaGo cells, human lung bronchogenic carcinoma cells; DMBA, dimethylbenzanthracene; alpha-hCG, the alpha subunit of human chorionic gonadotropin; alpha-hCG mRNA, alpha-hCG-specific mRNA sequences; PAHs, polycyclic aromatic hydrocarbons; SSC, 3 M NaC! and 0.3 M sodium acetate. accepted as the prototype (2, 3). Ectopic hormone and inappropriate gene expression are commonly found to be associated with neoplastic transformation of cells. BaP and several other members of the PAHs have been found to induce aryl hydrocarbon hydroxylase (AHH) in different mammalian cell systems (4). These inducers of AHH also enhance the expression of alpha-fetoprotein gene (5); activities of phospho...

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“…Dihydroriboflavin also protects against reperfusion oxidative damage by reducing oxidized iron in hemeproteins [109,110]. Riboflavin directly scavenges for free radicals produced by mutagens, thereby inhibiting their mutagenicity [111].…”

Section: Vitaminsmentioning

confidence: 99%

Vitreous Antioxidants, Degeneration, and Vitreo-Retinopathy: Exploring the Links

Ankamah

Sebag²,

et al. 2019

Antioxidants

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The transparent vitreous body, which occupies about 80% of the eye’s volume, is laden with numerous enzymatic and non-enzymatic antioxidants that could protect the eye from oxidative stress and disease. Aging is associated with degeneration of vitreous structure as well as a reduction in its antioxidant capacity. A growing body of evidence suggests these age-related changes may be the precursor of numerous oxidative stress-induced vitreo-retinopathies, including vision degrading myodesopsia, the clinically significant entoptic phenomena that can result from advanced vitreous degeneration. Adequate intravitreal antioxidant levels may be protective against vitreous degeneration, possibly preventing and even improving vision degrading myodesopsia as well as mitigating various other vitreo-retinopathies. The present article is, therefore, a review of the different antioxidant molecules within vitreous and the inter-relationships between vitreous antioxidant capacity and degeneration.

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Mechanism of the inhibition of mutagenicity of a benzo[a]pyrene 7,8-diol 9,10-epoxide by riboflavin 5'-phosphate.

Cited by 38 publications

References 26 publications

Hetero-association of aromatic molecules in aqueous solution

Hetero-association of aromatic molecules in aqueous solution

Mechanism of benzo(a)pyrene induction of alpha-human chorionic gonadotropin gene expression in human lung tumor cells.

Vitreous Antioxidants, Degeneration, and Vitreo-Retinopathy: Exploring the Links

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