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Emixustat Hydrochloride
Emixustat is a small molecule notable for its establishment of a new class of compounds known as visual cycle modulators (VCMs). Formulated as the hydrochloride salt, emixustat hydrochloride, it is the first synthetic medicinal compound shown to affect retinal disease processes when taken by mouth. Emixustat was invented by the British-American chemist, Ian L. Scott, and is currently in Phase 3 trials for dry, age-related macular degeneration (AMD). The compound is also being investigated as a potential therapy for proliferative diabetic retinopathy, diabetic macular edema and Stargardt disease. In 2008, Acucela Inc. partnered with Otsuka Pharmaceutical Company for the development of emixustat (ACU-4429) in an agreement totaling $263 million in cash and milestone payments. Emixustat hydrochloride is a non-retinoid small molecule inhibitor of RPE65 (retinal pigment epithelium-specific 65 kDa protein, also known as retinoid isomerohydrolase). It is thought to reduce visual chromop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloride
In chemistry, a hydrochloride is an acid salt resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base (e.g. an amine). An alternative name is chlorhydrate, which comes from French. An archaic alternative name is muriate, derived from hydrochloric acid's ancient name: muriatic acid. Uses Converting amines into their hydrochlorides is a common way to improve their water solubility, which can be desirable for substances used in medications. The European Pharmacopoeia lists more than 200 hydrochlorides as active ingredients in medications. These hydrochlorides, compared to free bases, may more readily dissolve in the gastrointestinal tract and be absorbed into the bloodstream more quickly. Additionally, many hydrochlorides of amines have a longer shelf-life than their respective free bases. Amine hydrochlorides represent latent forms of a more reactive free base. In this regard, formation of an amine hydrochloride confers protection. This eff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions. The component ions in a salt compound can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as fluoride (F−), or polyatomic, such as sulfate (). Types of salt Salts can be classified in a variety of ways. Salts that produce hydroxide ions when dissolved in water are called ''alkali salts'' and salts that produce hydrogen ions when dissolved in water are called ''acid salts''. ''Neutral salts'' are those salts that are neither acidic nor basic. Zwitterions contain an anionic and a cationic centre in the same molecule, but are not considered salts. Examples of zwitterions are amino acids, many metabolites, peptid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Age-related Macular Degeneration
Macular degeneration, also known as age-related macular degeneration (AMD or ARMD), is a medical condition which may result in blurred or no vision in the center of the visual field. Early on there are often no symptoms. Over time, however, some people experience a gradual worsening of vision that may affect one or both eyes. While it does not result in complete blindness, loss of central vision can make it hard to recognize faces, drive, read, or perform other activities of daily life. Visual hallucinations may also occur. Macular degeneration typically occurs in older people. Genetic factors and smoking also play a role. It is due to damage to the macula of the retina. Diagnosis is by a complete eye exam. The severity is divided into early, intermediate, and late types. The late type is additionally divided into "dry" and "wet" forms with the dry form making up 90% of cases. The difference between the two forms is the change of macula. Those with dry form AMD have drusen, ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetic Retinopathy
Diabetic retinopathy (also known as diabetic eye disease), is a medical condition in which damage occurs to the retina due to diabetes mellitus. It is a leading cause of blindness in developed countries. Diabetic retinopathy affects up to 80 percent of those who have had both type 1 and type 2 diabetes for 20 years or more. In at least 90% of new cases, progression to more aggressive forms of sight threatening retinopathy and maculopathy could be reduced with proper treatment and monitoring of the eyes The longer a person has diabetes, the higher his or her chances of developing diabetic retinopathy. Each year in the United States, diabetic retinopathy accounts for 12% of all new cases of blindness. It is also the leading cause of blindness in people aged 20 to 64. Signs and symptoms Nearly all people with diabetes develop some degree of retina damage ("retinopathy") over several decades with the disease. For many, that damage can only be detected by a retinal exam, and has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetic Macular Edema
Diabetic retinopathy (also known as diabetic eye disease), is a medical condition in which damage occurs to the retina due to diabetes mellitus. It is a leading cause of blindness in developed countries. Diabetic retinopathy affects up to 80 percent of those who have had both type 1 and type 2 diabetes for 20 years or more. In at least 90% of new cases, progression to more aggressive forms of sight threatening retinopathy and maculopathy could be reduced with proper treatment and monitoring of the eyes The longer a person has diabetes, the higher his or her chances of developing diabetic retinopathy. Each year in the United States, diabetic retinopathy accounts for 12% of all new cases of blindness. It is also the leading cause of blindness in people aged 20 to 64. Signs and symptoms Nearly all people with diabetes develop some degree of retina damage ("retinopathy") over several decades with the disease. For many, that damage can only be detected by a retinal exam, and has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stargardt Disease
Stargardt disease is the most common inherited single-gene retinal disease. In terms of the first description of the disease, it follows an autosomal recessive inheritance pattern, which has been later linked to bi-allelic ABCA4 gene variants (STGD1). However, there are Stargardt-like diseases with mimicking phenotypes that are referred to as STGD3 and STGD4, and have a autosomal dominant inheritance due to defects with ELOVL4 or PROM1 genes, respectively. It is characterized by macular degeneration that begins in childhood, adolescence or adulthood, resulting in progressive loss of vision. Signs and symptoms The presentation usually occurs in childhood or adolescence, though there is no upper age limit for presentation and late-onset is possible. The main symptom is loss of visual acuity, uncorrectable with glasses. This manifests as the lack of the ability to see fine details when reading or viewing distant objects. Symptoms typically develop before age 20 (median age of ons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otsuka Pharmaceutical
(), abbreviated OPC, is a pharmaceutical company headquartered in Tokyo, Osaka and Naruto, Japan. The company was established August 10, 1964. History OPC's parent company Otsuka Holdings Co. Ltd. joined the Tokyo Stock Exchange through an initial public offering (IPO) on December 15, 2010, at which time Otsuka Holdings was Japan's No.2 drug maker by sales after industry leader Takeda Pharmaceutical Company. The IPO debuted at $2.4 billion, making it the largest for a pharmaceutical company up to that time. Otsuka Pharmaceutical Co. LTD Holdings In 1955, the company started a football club called "Otsuka Pharmaceutical SC." In 2005 the name changed to Tokushima Vortis. The club is based in Naruto. In 2008, Otsuka Pharmaceutical Co. acquired 49% of Alma S.A., which is the parent company of CG Roxane. In March 2017, the company agreed to acquire Neurovance, Inc. for $250 million, gaining the firm’s Phase III-ready ADHD drug centanafadine (previously EB-1020). Otsuka's su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RPE65
Retinal pigment epithelium-specific 65 kDa protein, also known as retinoid isomerohydrolase, is an enzyme of the vertebrate visual cycle that is encoded in humans by the ''RPE65'' gene. RPE65 is expressed in the retinal pigment epithelium (RPE, a layer of epithelial cells that nourish the photoreceptor cells) and is responsible for the conversion of all-trans- retinyl esters to 11-cis-retinol during phototransduction. 11-cis-retinol is then used in visual pigment regeneration in photoreceptor cells. RPE65 belongs to the carotenoid oxygenase family of enzymes. Function RPE65 is a critical enzyme in the vertebrate visual cycle found in the retinal pigmented epithelium. It is also found in rods and cones. The photoisomerization of 11-cis-retinal to all-trans-retinal initiates the phototransduction pathway through which the brain detects light. All-trans-retinol is not photoactive and therefore must be reconverted to 11-cis-retinal before it can recombine with opsin to form an acti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Cycle
The visual cycle is a process in the retina that replenishes the molecule retinal for its use in vision. Retinal is the chromophore of most visual opsins, meaning it captures the photons to begin the phototransduction cascade. When the proton is absorbed, the ''11-cis retinal'' photoisomerizes into ''all-trans retinal'' as it is ejected from the opsin protein. Each molecule of retinal must travel from the photoreceptor cell to the RPE and back in order to be refreshed and combined with another opsin. This closed enzymatic pathway of ''11-cis retinal'' is sometimes called Wald's visual cycle after George Wald (1906–1997), who received the Nobel Prize in 1967 for his work towards its discovery. Retinal Retinal is a chromophore that forms photosensitive Retinylidene proteins when covalently bound to proteins called opsins. Retinal can be photoisomerized by itself, but requires to be bound to an opsin protein to both trigger the phototransduction cascade and tune the spectral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Phototransduction
Visual phototransduction is the sensory transduction process of the visual system by which light is detected to yield nerve impulses in the rod cells and cone cells in the retina of the eye in humans and other vertebrates. It relies on the visual cycle, a sequence of biochemical reactions in which a molecule of retinal bound to opsin undergoes photoisomerization, initiates a cascade that signals detection of the photon, and is indirectly restored to its photosensitive isomer for reuse. Phototransduction in some invertebrates such as fruit flies relies on similar processes. Photoreceptors The photoreceptor cells involved in vertebrate vision are the rods, the cones, and the photosensitive ganglion cells (ipRGCs). These cells contain a chromophore ( 11-''cis''-retinal, the aldehyde of vitamin A1 and light-absorbing portion) that is bound to a cell membrane protein, opsin. Rods deal with low light level and do not mediate color vision. Cones, on the other hand, can code the color o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodopsin
Rhodopsin, also known as visual purple, is a protein encoded by the RHO gene and a G-protein-coupled receptor (GPCR). It is the opsin of the rod cells in the retina and a light-sensitive receptor protein that triggers visual phototransduction in rods. Rhodopsin mediates dim light vision and thus is extremely sensitive to light. When rhodopsin is exposed to light, it immediately photobleaches. In humans, it is regenerated fully in about 30 minutes, after which the rods are more sensitive. Defects in the rhodopsin gene cause eye diseases such as retinitis pigmentosa and congenital stationary night blindness. Names Rhodopsin was discovered by Franz Christian Boll in 1876. The name rhodospsin derives from Ancient Greek () for "rose", due to its pinkish color, and () for "sight". It was coined in 1878 by the German physiologist Wilhelm Friedrich Kühne (1837-1900). When George Wald discovered that rhodopsin is a holoprotein, consisting of retinal and an apoprotein, he c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinal
Retinal (also known as retinaldehyde) is a polyene chromophore. Retinal, bound to proteins called opsins, is the chemical basis of visual phototransduction, the light-detection stage of visual perception (vision). Some microorganisms use retinal to convert light into metabolic energy. In fact, a recent study suggests most living organisms on our planet ~3 billion years ago used retinal to convert sunlight into energy rather than chlorophyll. Since retinal absorbs mostly green light and transmits purple light, this gave rise to the Purple Earth Hypothesis. There are many forms of vitamin A — all of which are converted to retinal, which cannot be made without them. Retinal itself is considered to be a form of vitamin A when eaten by an animal. The number of different molecules that can be converted to retinal varies from species to species. Retinal was originally called retinene, and was renamed after it was discovered to be vitamin A aldehyde. Vertebrate animals ingest reti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
