Binding affinities of a new and unusual series of retinoic acid analogues to cellular retinoic acid-binding protein, a possible mediator of their biological function in the control of differentiation and tumorigenesis, and to serum albumin, their plasma transport protein, were determined. Also, biological activity of these retinoids in the reversal of keratinization in hamster trachéalorgan cu...

A separation procedure for retinoids based on reversephase high-pressure liquid chromatography with solvent mixtures of acetonitrile and water is described. The method may be applied to the screening of synthetic retinoids, which have potential for use in the prevention of cancer. It is easily adapted to a variety of biological samples and can be applied to other conventional retinoid assays in...

Maturation of dendritic cells (DCs) is a critical step for the induction of an immune response. We have examined the role of retinoid nuclear receptor pathways in this process. Retinoids induce DC apoptosis, in the absence of inflammatory signals, through retinoic acid receptor (RAR)alpha/retinoic X receptor (RXR) heterodimers. In contrast, via a cross talk with inflammatory cytokines, retinoid...

Many properties of chemicals depend on their stereochemistry. Among these, the effects of stereoisomerism on percutaneous absorption of drugs are not well studied. We have previously shown that permeation of tretinoin and isotretinoin (two geometric isomers) through hydrophilic enhancers-treated rat skin is stereoselective. As, depending on their lipophilicity, penetration enhancers can change ...

Many properties of chemicals depend on their stereochemistry. Among these, the effects of stereoisomerism on percutaneous absorption of drugs are not well studied. We have previously shown that permeation of tretinoin and isotretinoin (two geometric isomers) through hydrophilic enhancers-treated rat skin is stereoselective. As, depending on their lipophilicity, penetration enhancers can change ...

The clinical efficacy of retinoids in benign and malignant skin diseases involving immune mechanisms suggests that they affect the immunologic functions of the epidermis. However, these effects have yet to be demonstrated. The action of vitamin A (retinol) and the synthetic retinoids, isotretinoin, etretinate, acitretin, and arotinoid-free acid have been studied on the lymphocyte proliferation ...

BACKGROUND Retinoids are very potent inducers of cellular differentiation and apoptosis, and are efficient anti-tumoral agents. Synthetic retinoids are designed to restrict their toxicity and side effects, mostly by increasing their selectivity toward each isotype of retinoic acids receptors (RARalpha,beta, gamma and RXRalpha, beta, gamma). We however previously showed that retinoids displayed ...

Retinoids mediate their actions via RARs (retinoic acid receptors) and RXRs (retinoid X receptors). Each class of these nuclear retinoid receptors is further subdivided into three species, namely alpha, beta, and gamma. Recent studies demonstrate that estrogen receptor (ER)-positive human breast carcinoma (HBC) cell lines and tumor samples exhibit significantly higher levels of RAR alpha than t...

Through its various metabolites, vitamin A controls essential physiological functions. Both naturally occurring metabolites and novel retinoid analogues have shown effectiveness in many clinical settings that include skin diseases and cancer, and in animal models of human conditions affecting vision. In this review, we analyze several potential retinoid-based therapies from the point of view of...