- Lysosomal Reacidification Ameliorates Vinyl Carbamate-Induced Toxicity and Disruption on Lysosomal pH
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Ethyl carbamate (EC) is a carcinogen toxicant, commonly found in fermented foods and beverages. The carcinogenic and toxic possibility of EC is thought to be related to its metabolite vinyl carbamate (VC). However, we found interesting mechanisms underlying VC-induced toxicity in this study, which were greatly different from EC. We first conducted a simple synthesis procedure for VC and found that VC possessed higher toxicity but failed to regulate levels of reactive oxygen species, glutathione, and autophagy. Notably, VC treatment resulted in upregulation of lysosomal pH, which was responsible for its cytotoxicity. Cyclic adenosine monophosphate (cAMP) pretreatment could enhance restoration of lysosomal acidity and ameliorate VC-induced damage. Inhibition of protein kinase A and cystic fibrosis transmembrane conductance regulator can block cAMP-induced cytoprotection. Together, our results provided the evidence for novel mechanisms of toxicity and possible protection method under VC exposure, which might give new perspectives on the study of EC-induced toxicity.
- Chen, Wei,Cui, Sunliang,Hu, Dongwen,Li, Yuting,Qi, Jifeng
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p. 8951 - 8961
(2020/09/16)
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- Biomaterials based on low cytotoxic vinyl esters for bone replacement application
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In recent days, additive manufacturing technologies (AMT) based on photopolymerization have also found application in tissue engineering. Although acrylates and methacrylates have excellent photoreactivity and afford photopolymers with good mechanical properties, their cytotoxicity and degradation products disqualify them from medical use. Within this work, (meth)acrylate-based monomers were replaced by vinyl esters with exceptional low cytotoxicity. The main focus of this paper lies on the determination of the photoreactivity and investigations concerning mechanical properties and degradation behavior of the new materials. Tested monomers provide sufficient photoreactivity for processing by AMT. Mechanical properties similar to natural bone could be obtained by adding suitable fillers like hydroxylapatite (HA). The right ratio of hydrophobic and hydrophilic monomers allows the tuning of the degradation behavior. Finally, with the optimum formulation, cellular 3D structures were built using digital light processing.
- Husar, Branislav,Heller, Christian,Schwentenwein, Martin,Mautner, Andreas,Varga, Franz,Koch, Thomas,Stampfl, Juergen,Liska, Robert
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experimental part
p. 4927 - 4934
(2012/06/01)
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- β-Phenylselenoethanol, an efficient reagent for the one-pot synthesis of aryl vinyl ethers
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β-Phenylselenoethanol was treated with phenols under Mitsunobu conditions and subsequent oxidation-elimination with 30% hydrogen peroxide furnished aryl vinyl ethers with good yields (85-90%) in a one-pot, two-step transformation.
- Fu, Gui-Yun,Yu, La-Mei,Mao, Xue-Chun,Wu, Dan
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experimental part
p. 595 - 597
(2009/10/15)
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- Synthesis and ABTS radical, MMP-1 inhibitory activity of CAPE analogues
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In the photoaging process of skin, the ultraviolet (UV)-induced reactive oxygen species (ROS) is the key regulator of matrix metalloproteinase (MMPs) expression. In this study, a series of Caffeic acid phenethyl ester (CAPE) analogues were synthesized by
- Chiang, Chih-Chia,Hsu, Ling-Yih,Chang, Tsu-Chung,Tsai, Hou-Jen
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experimental part
p. 698 - 703
(2009/05/30)
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- Synthesis of selenium-containing polyphenolic acid esters and evaluation of their effects on antioxidation and 5-lipoxygenase inhibition
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Six novel selenium-containing polyphenolic acid esters were synthesized and evaluated as antioxidants and 5-lipoxygenase inhibitors. Synthesis of the title compounds involved the Mitsunobu reaction of polyphenolic acids (4-8, 14) with 2-phenylselenoethanol (3). Compounds 22, 23, and 25 were found to be very effective antioxidants and 5-lipoxygenase inhibitors with activity comparable to or better than caffeic acid (3,4-dihydroxycinnamic acid) phenethyl ester (CAPE).
- Lin, Chi-Fu,Chang, Tsu-Chung,Chiang, Chih-Chia,Tsai, Hou-Jen,Hsu, Ling-Yih
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p. 1402 - 1407
(2007/10/03)
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- General synthesis of alkyl phenyl selenides from organic halides mediated by zinc in aqueous medium
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Organic halides of different structural types react with diphenyl diselenide and zinc dust in aqueous medium to give alkyl phenyl selenides. Benzylic and allylic bromides, α-bromoesters, acids and ketones and some primary alkyl iodides produce high yields even under acidic conditions. Less reactive halides need basic medium. The reaction proceeds equally well in the presence of various unprotected functional groups. Control experiments support a SH2 mechanism via alkyl radicals.
- Bieber, Lothar W.,De Sá, Ana C.P.F.,Menezes, Paulo H.,Gon?alves, Simone M.C.
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p. 4597 - 4599
(2007/10/03)
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- Reductive Cleavage of the Se-Se Bond by the Sm-Me3SiCl-H2O System: Preparation of Unsymmetrical Phenyl Selenides
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The reduction of diphenyl diselenide by the Sm-Me3SiCl-H2O system led to a selenide anion. This 'living' species reacted with organic halides, epoxides, α,β-unsaturated esters and α,β-unsaturated nitrtles to afford unsymmetrical phenylselenides in good yields under mild and neutral conditions.
- Wang, Lei,Zhang, Yongmin
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p. 598 - 599
(2007/10/03)
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- Method of treating drug resistant tumor cells using organoselenones
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Organoselenones of the formula wherein R1 is selected from the group consisting of aryl, vinyl, acetylenyl, and aralkyl, n is an integer equal to 2 to 6 and X is a leaving group selected from the group consisting of halides, sulfonates and
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- Intramolecular SH2 macrocyclisations
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The synthesis of 10-15 membered α-methylene macrocyclic lactones from the functionalised allylstannanes (7e)-(7j) is described. Attempts to synthesise analogous 6-9 membered lactones proved unsuccessful, resulting instead in the production of dilactones and AIBN derived adducts.
- Baldwin, Jack E.,Adlington, Robert M.,Mitchell, Mark B.,Robertson, Jeremy
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p. 5901 - 5918
(2007/10/02)
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- A New Route to Epoxides and Ketones by m-Chloroperbenzoic Acid Oxidation of β-Hydroxyalkyl Phenyl Selenides and Tellurides
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Treatment of primary (β-hydroxy)alkyl phenyl selenides with m-chloroperbenzoic acid (3-5 mol equiv.) in tetrahydrofuran or methanol gives the corresponding epoxides in high yield. cis-1-Methylene-4-t-butylcyclohexane oxide is obtained stereospecifically from 4-t-butyl-1-(phenylselenomethyl)cyclohexanol prepared by the addition of α-(phenylseleno)methyl anion to 4-t-butylcyclohexanone.On the other hand, similar oxidation of secondary (β-hydroxy)alkyl phenyl selenides affords the unexpected carboxylic acids or their esters.When a phenyl group is present on the carbon bearing the OH moiety in β-hydroxyselenides and tellurides , the oxidation is accompanied by phenyl migration to afford ketones.The reaction can be applied to one-carbon-homologated ring expansion of the benzene-ring-fused cyclic ketones by combining with the addition of an α-(phenylseleno)methyl or α-(phenyltelluro)methyl moiety to the ketones.
- Uemura, Sakae,Ohe, Kouichi,Sugita, Nobuyuki
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p. 1697 - 1703
(2007/10/02)
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- Organic Tellurium and Selenium Chemistry. Reduction of Tellurides, Selenides, and Selenoacetals with Triphenyltin Hydride
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Preparative and mechanistic details are described for the conversion of selenides into hydrocarbons RH> by heating with triphenyltin hydride at about 120 deg C.The process has been extended to selenoacetals in a form that constitutes a reduction methods for carbonyl compounds RR'C(SePh)2 -> RR'CH2>.Selective reduction of selenoacetals in the presence of thioacetals is possible.Cold-labeled species can be prepared by using triphenyltin deuteride.Tellurides are available easily without problems arising from exposure to air provided that the work is done in a photographic darkroom equipped with a red safety light.These tellurides, as well as the corresponding dichlorides , are reduced under very mild conditions (25-80 deg C) by triphenyltin hydride.The selenium- and tellurium-based chemistry has been used for the unusual process of reducing an epoxide in the presence of a ketone carbonyl.
- Clive, Derrick L. J.,Chittattu, Gim J.,Farina, Vittorio,Kiel, William A.,Menchen, Steven M.,et al.
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p. 4438 - 4447
(2007/10/02)
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