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Retinoid Transfer By CRABP1
The retinoids are a class of chemical compounds that are natural derivatives of vitamin A or are chemically related to it. Synthetic retinoids are utilized in cosmetic formulations, clinical dermatology, and the treatment of some forms of cancer. Retinoids have many important functions throughout the body, including in vision, regulation of skin proliferation and differentiation, growth of bone tissue, immune function, and male fertility. The biology of retinoids is complex, having well-documented effectiveness in the management of conditions ranging from acute promyelocytic leukemia to acne to photoaging. On the other hand, retinoids may be involved in metabolic dysfunction and, at least in some forms, carcinogenesis. Types Retinoids are divided into four generations based on their molecular structure and receptor selectivity. Structure The basic structure of the hydrophobic retinoid molecule consists of a cyclic end group, a polyene side chain and a polar end group. The c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oleyl Adapalenate
Oleyl adapalenate, sold under the brand name Adapinoid, is a lipophilic derivative of adapalene, and is a third-generation synthetic retinoid. It is primarily utilized in topical cosmetic formulations for the treatment of skin conditions associated with photoaging, rhytides (wrinkles), and acne induced post-inflammatory erythema, post-inflammatory hyperpigmentation, and scarring. Oleyl adapalenate differentiates itself from earlier retinoids by offering improved skin tolerability, reduced irritation, and enhanced stability. Structure The structure of oleyl adapalenate is similar to that of adapalene, but with oleyl alcohol covalently bound via an ester bond to the free carboxylate group of adapalene. The lipophillic character of oleyl adapalenate allows it to be soluble in skincare oils and emollients, whereas adapalene, being neither lipophilic nor hydrophilic, has low solubility in solvents and is limited in how it can be compounded and delivered in topical drugs. Uses Be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinoid X Receptor
The retinoid X receptor (RXR) is a type of nuclear receptor that is activated by 9-cis retinoic acid, which is discussed controversially to be of endogenous relevance, and 9-''cis''-13,14-dihydroretinoic acid, which may be an endogenous mammalian RXR-selective agonist. Bexarotene is the only specific activator of the RXRs which does not activate the Retinoic Acid Receptors. There are three retinoic X receptors (RXR): RXR-alpha, RXR-beta, and RXR-gamma, encoded by the , , genes, respectively. RXR heterodimerizes with multiple nuclear receptors including CAR, FXR, LXR, PPAR, PXR, RAR, TR, ER and VDR. RXRs are permissive co-receptors as only one of six alleles is needed for normal development and health. Given this, it is difficult to extrapolate whether the RXR pathway has its own endogenous activity driven by 9-cis retinoic acid species or whether it merely participates in other pathways, predominantly the retinoic nuclear receptor pathway. Genomic knockout of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
13-cis Retinoic Acid
Isotretinoin, also known as 13-''cis''-retinoic acid and sold under the brand name Accutane among others, is a medication used to treat skin diseases like harlequin-type ichthyosis, and lamellar ichthyosis, and severe cystic acne or moderate acne that is unresponsive to antibiotics. Isotretinoin is used off-label to treat basal cell carcinoma and squamous cell carcinoma, although clinical evidence suggests it is not effective in this setting. It is a retinoid, meaning it is related to vitamin A, and is found in small quantities naturally in the body. Its isomer, tretinoin, is also an acne drug. The most common adverse effects are dry lips ( cheilitis), dry and fragile skin (xeroderma), dry eyes and an increased susceptibility to sunburn. Uncommon and rare side effects include muscle aches and pains (myalgias), and headaches. Some of those side effects can persist long after the discontinuation of the use of the drug. Isotretinoin may cause liver failure, therefore the pat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9-cis-retinoic Acid
Alitretinoin, or 9-cis-retinoic acid, is a form of vitamin A. It is also used in medicine as an antineoplastic (anti-cancer) agent developed by Ligand Pharmaceuticals. It is a first generation retinoid. Ligand gained Food and Drug Administration (FDA) approval for alitretinoin in February 1999. Medical uses Kaposi's sarcoma In the United States, topical alitretinoin is indicated for the treatment of skin lesions in AIDS-related Kaposi's sarcoma. Alitretinoin is not indicated when systemic therapy against Kaposi's sarcoma is required. It has received EMA (11 October 2000) and FDA (2 March 1999) approval for this indication. Chronic hand eczema Alitretinoin has been granted prescription rights in the UK (08/09/2008) for in chronic hand eczema as used by mouth. In May 2009 the National Institute for Health and Clinical Excellence (NICE) issued preliminary guidance on the use of alitretinoin for the treatment of severe chronic hand eczema in adults. The recommendation stated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
All-trans-retinoic Acid
Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For acute promyelocytic leukemia, it is effective only when the RARA-PML fusion mutation is present and is taken by mouth for up to three months. Topical tretinoin is also the most extensively investigated retinoid therapy for photoaging. Common side effects when used as a cream are limited to the skin and include skin redness, peeling, and sun sensitivity. When taken by mouth, side effects include hypertriglyceridemia, hypercholesterolemia, shortness of breath, headache, numbness, depression, skin dryness, itchiness, hair loss, vomiting, muscle pains, and vision changes. Other severe side effects include high white blood cell counts and blood clots. Use during pregnancy is contraindicated due to the risk of birth defects. It is in the retinoid family of medications. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinoic Acid Receptor
The retinoic acid receptor (RAR) is a type of nuclear receptor which can also act as a ligand-activated transcription factor that is activated by both all-trans retinoic acid and 9-cis retinoic acid, retinoid active derivatives of Vitamin A. They are typically found within the nucleus. There are three retinoic acid receptors (RAR), RAR-alpha, RAR-beta, and RAR-gamma, encoded by the , , genes, respectively. Within each RAR subtype there are various isoforms differing in their N-terminal region A. Multiple splice variants have been identified in human RARs: four for , five for , and two for . As with other type II nuclear receptors, RAR heterodimerizes with RXR and in the absence of ligand, the RAR/RXR dimer binds to hormone response elements known as retinoic acid response elements (RAREs) complexed with corepressor protein. Binding of agonist ligands to RAR results in dissociation of corepressor and recruitment of coactivator protein that, in turn, promotes transcript ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinol Binding Protein 4
Retinol binding protein 4, also known as RBP4, is a transporter protein for retinol (vitamin A alcohol). RBP4 has a molecular weight of approximately 21 kDa and is encoded by the ''RBP4'' gene in humans. It is mainly, though not exclusively, synthesized in the liver and circulates in the bloodstream as a hepatokine bound to retinol in a complex with transthyretin. RBP4 has been a drug target for ophthalmology research due to its role in vision. RBP4 may also be involved in metabolic diseases as suggested by recent studies. Function This protein belongs to the lipocalin family and is the specific carrier for retinol (vitamin A) in the blood. It delivers retinol from the liver stores to the peripheral tissues. In plasma, the RBP-retinol complex interacts with transthyretin, which prevents its loss by filtration through the kidney glomerulus (kidney), glomeruli. A deficiency of vitamin A blocks secretion of the binding protein posttranslationally and results in defective delivery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromophore
A chromophore is the part of a molecule responsible for its color. The word is derived . The color that is seen by our eyes is that of the light not Absorption (electromagnetic radiation), absorbed by the reflecting object within a certain wavelength spectrum of visible spectrum, visible light. The chromophore is a region in the molecule where the energy difference between two separate molecular orbitals falls within the range of the visible spectrum (or in informal contexts, the spectrum under scrutiny). Visible light that hits the chromophore can thus be absorbed by exciting an electron from its ground state into an excited state. In biological molecules that serve to capture or detect light energy, the chromophore is the Moiety (chemistry), moiety that causes a conformational change in the molecule when hit by light. Conjugated pi-bond system chromophores Just like how two adjacent p-orbitals in a molecule will form a pi-bond, three or more adjacent p-orbitals in a molec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conjugated System
In physical organic chemistry, a conjugated system is a system of connected p-orbitals with delocalized electrons in a molecule, which in general lowers the overall energy of the molecule and increases Chemical stability, stability. It is Resonance (chemistry), conventionally represented as having alternating single and multiple covalent bond, bonds. Lone pairs, radical (chemistry), radicals or carbenium ions may be part of the system, which may be Cyclic molecule, cyclic, acyclic, Linear molecular geometry, linear or mixed. The term "conjugated" was coined in 1899 by the German chemist Johannes Thiele (chemist), Johannes Thiele. Conjugation is the orbital overlap, overlap of one p-orbital with another across an adjacent Sigma bond, σ bond (in transition metals, d-orbitals can be involved). A conjugated system has a region of overlapping p-orbitals, bridging the interjacent locations that simple diagrams illustrate as not having a π bond. They allow a delocalization of pi el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyene
In organic chemistry, polyenes are polyunsaturated organic compounds that contain multiple carbon–carbon double bonds (). Some sources consider dienes to be polyenes, whereas others require polyenes to contain at least three carbon–carbon double bonds. Conjugated polyenes contain a conjugated system of alternating single and double carbon–carbon bonds, with characteristic optical properties. The following polyenes are used as antimycotics for humans: amphotericin B, nystatin, candicidin, pimaricin, methyl partricin, and trichomycin. Optical properties Some polyenes are brightly colored, an otherwise rare property for a hydrocarbon. Normally alkenes absorb in the ultraviolet region of a spectrum, but the absorption energy state of polyenes with numerous conjugated double bonds can be lowered such that they enter the visible region of the spectrum, resulting in compounds which are coloured (because they contain a chromophore). Thus many natural dyes contain linear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
