Free Radical Oxidation of (E)-Retinoic Acid by Prostaglandin H Synthase
摘要:
Cooxidative metabolism of all-trans (E)-retinoic acid (RA) by prostaglandin H synthase was investigated employing ram seminal vesicle microsomes (RSVM) or purified, RSVM-derived enzyme. RA was shown to undergo hydroperoxide [H2O2 or 5-phenyl-4-penten-1-yl hydroperoxide (PPHP)]- or arachidonic acid-dependent cooxidation by microsomal prostaglandin H (PGH) synthase as evidenced by UV spectroscopic analysis of reaction mixtures. Cooxidation of RA by microsomal or purified PGH synthase, using PPHP as substrate, was characterized by uptake of dioxygen which was first order with respect to enzyme concentration. Dioxygen uptake was inhibited by the peroxidase reducing substrate 2-methoxyphenol. In addition, O-2 uptake was inhibited by the spin trap nitrosobenzene. ESR spin trapping studies, using alpha-phenyl-N-tert-butylnitrone (PBN) as the spin trap, demonstrated the formation of RA-PBN adducts, characterized by hyperfine coupling constants of a(H) = 3.2 G and a(N) = 15.8 G. Reverse phase HPLC analysis of reaction mixtures demonstrated the formation of 4-hydroxy-RA, 5,6-epoxy-RA, 4-oxo-RA, (13Z)-retinoic acid, and other geometric isomers which were identified on the basis of cochromatography with synthetic standards, UV spectroscopy, and/or mass spectrometry. Mechanisms are proposed for the hydroperoxide-dependent, PGH synthase-catalyzed oxidation of RA that are consistent with these results.
Retinoic acid underwent autoxidation in 90% ethanol at 25–85.5 °C to give epoxides, dioxetanes, an endoperoxide, and double-bond cleavage products. The majority of these products appear to have resulted from the initial direct oxidation of the olefinic carbons rather than from the expected allylic α oxidation process.
[EN] METHOD FOR PRODUCING N-RETINOYLCYSTEIC ACID ALKYL ESTER<br/>[FR] PROCÉDÉ DE PRODUCTION D'ESTER ALKYLIQUE DE L'ACIDE N-RÉTINOYLCYSTÉIQUE
申请人:ARDENIA INVESTMENTS LTD
公开号:WO2017099662A1
公开(公告)日:2017-06-15
A method for producing derivatives of N-retinoylaminoalkane sulfonic acid, the method comprising providing retinoic acid, chloroformate, aminoalkanesulfonic acid selected from the group consisting of cysteic acidand alkyl ester thereof, cysteinesulfinic acid and alkyl ester thereof, homocysteic acid and alkyl ester thereof, homocysteinesulfinic acid and alkyl esters thereof, taurine and derivatives thereof, and an organic solvent,and a base, mixing said components under substantial absence of oxidizing compoundsthereby forming a reaction mixture comprising a liquid phase, wherein the liquid phase is one phaseand the derivatives of N-retinoylaminoalkane sulfonic acid are formed in said liquid phase.
The present invention relates to novel receptor polypeptides, which, upon interaction with certain ligands, or activation by certain compounds, modulate transcription of certain genes by binding to cognate response elements associated with promoters of such genes. The novel receptors of the invention modulate transcription in the presence of retinoid compounds. The receptors of the present invention differ significantly from known retinoid acid receptors, in protein primar yseqence and in responsiveness to exposure to various retinoids. The invention provides DNAs encoding the novel receptors, expression vectors for expression of the receptors, cells transformed with such expression vectors, cells co-transformed with such expression vectors and with reporter vectors to monitor modulation of transcription by the receptors, and methods of using such co-transformed cells in screening for compounds which are capable, directly or indirectly, of activating the receptors. The invention also provides nucleic acid probes for identifying DNAs which encode additional retinoid receptors of the same class as the novel receptors disclosed herein.
本发明涉及新型受体多肽,它们在与某些配体相互作用或被某些化合物激活后,通过与与这些基因启动子相关的同源反应元件结合,调节某些基因的转录。本发明的新型受体可在视黄醇化合物存在的情况下调节转录。本发明的受体与已知的视黄酸受体在蛋白质序列和对各种视黄酸的反应性方面有很大不同。本发明提供了编码新型受体的 DNA、表达受体的表达载体、用这种表达载体转化的细胞、用这种表达载体和报告载体共同转化的细胞以监测受体对转录的调节,以及用这种共同转化的细胞筛选能直接或间接激活受体的化合物的方法。本发明还提供了用于鉴定 DNA 的核酸探针,这些 DNA 编码与本发明公开的新型受体属于同一类的其他视黄醇受体。
Factor for regulation of neurite growth
申请人:Oxford Biomedica (UK) Ltd
公开号:EP1762243A1
公开(公告)日:2007-03-14
The present invention relates to the use of RARβ2 and/or an agonist thereof in the preparation of a medicament to cause neurite development.