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Cholesterol Esters
file:Cholesterol oleate.svg, 300px, Cholesterol oleate, a member of the cholesteryl ester family Cholesteryl ester, a dietary lipid, is an ester of cholesterol. The ester bond is formed between the carboxylate group of a fatty acid and the hydroxyl group of cholesterol. Cholesteryl esters have a lower solubility in water due to their increased Hydrophobicity scales, hydrophobicity. Esters are formed by replacing at least one –OH (hydroxyl) group with an –O–alkyl (alkoxy) group. They are hydrolyzed by pancreatic enzymes, cholesterol esterase, to produce cholesterol and free fatty acids. They are associated with atherosclerosis. Cholesteryl ester is found in human brains as lipid droplets which store and transport cholesterol. Increased levels of cholesteryl ester have been found in certain parts of the brain of people with Huntington disease. Higher concentrations of cholesteryl ester have been found in the Caudate nucleus, caudate and putamen, but not the cerebellum, of people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholesterol Oleate
Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell membranes. When chemically isolated, it is a yellowish crystalline solid. Cholesterol also serves as a precursor for the biosynthesis of steroid hormones, bile acid and vitamin D. Cholesterol is the principal sterol synthesized by all animals. In vertebrates, hepatic cells typically produce the greatest amounts. It is absent among prokaryotes (bacteria and archaea), although there are some exceptions, such as ''Mycoplasma'', which require cholesterol for growth. François Poulletier de la Salle first identified cholesterol in solid form in gallstones in 1769. However, it was not until 1815 that chemist Michel Eugène Chevreul named the compound "cholesterine". Etymology The word "cholesterol" comes from the Ancient Greek ''chole-'' (bile) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Putamen
The putamen (; from Latin, meaning "nutshell") is a round structure located at the base of the forebrain (telencephalon). The putamen and caudate nucleus together form the dorsal striatum. It is also one of the structures that compose the basal nuclei. Through various pathways, the putamen is connected to the substantia nigra, the globus pallidus, the claustrum, and the thalamus, in addition to many regions of the cerebral cortex. A primary function of the putamen is to regulate movements at various stages (e.g. preparation and execution) and influence various types of learning. It employs GABA, acetylcholine, and enkephalin to perform its functions. The putamen also plays a role in degenerative neurological disorders, such as Parkinson's disease. History The word "putamen" is from Latin, referring to that which "falls off in pruning", from "putare", meaning "to prune, to think, or to consider". Until recently, most MRI research focused broadly on the basal ganglia as a who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lecithin–cholesterol Acyltransferase
Lecithin–cholesterol acyltransferase (LCAT, also called phosphatidylcholine–sterol O-acyltransferase) is an enzyme, in many animals including humans, that converts free cholesterol into cholesteryl ester (a more hydrophobic form of cholesterol), which is then sequestered into the core of a lipoprotein particle, eventually making the newly synthesized HDL spherical and forcing the reaction to become unidirectional since the particles are removed from the surface. The enzyme is bound to high-density lipoproteins (HDLs) (alpha-LCAT) and LDLs (beta-LCAT) in the blood plasma. LCAT deficiency can cause impaired vision due to cholesterol corneal opacities, anemia, and kidney damage. It belongs to the family of phospholipid:diacylglycerol acyltransferases. Interactive pathway map See also * Lecithin cholesterol acyltransferase deficiency Lecithin cholesterol acyltransferase deficiency is a disorder of lipoprotein metabolism. The disease has two forms: Familial LCAT deficiency, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acyl CoA Cholesteryl Acyltransferase
Sterol O-acyltransferase (also called Acyl-CoA cholesterol acyltransferase, Acyl-CoA cholesterin acyltransferase or simply ACAT) is an intracellular protein located in the endoplasmic reticulum that forms cholesteryl esters from cholesterol. Sterol O-acyltransferase catalyzes the chemical reaction: :acyl-CoA + cholesterol \rightleftharpoons CoA + cholesterol ester Thus, the two substrates of this enzyme are acyl-CoA and cholesterol, whereas its two products are CoA and cholesteryl ester. This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups, the membrane-bound O-acyltransferases. This enzyme participates in bile acid biosynthesis. Class and structure Acyl-CoA cholesterol acyl transferase , more simply referred to as ACAT, also known as sterol O-acyltransferase (SOAT), belongs to the class of enzymes known as acyltransferases. The role of this enzyme is to transfer fatty acyl groups fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholesteryl Ester Storage Disease
Lysosomal acid lipase deficiency (LAL deficiency or LAL-D) is an autosomal recessive inborn error of metabolism that results in the body not producing enough active lysosomal acid lipase (LAL) enzyme. This enzyme plays an important role in breaking down fatty material (cholesteryl esters and triglycerides) in the body. Infants, children and adults that have LAL deficiency experience a range of serious health problems. The lack of the LAL enzyme can lead to a build-up of fatty material in a number of body organs including the liver, spleen, gut, in the wall of blood vessels and other important organs. Very low levels of the LAL enzyme lead to LAL deficiency. LAL deficiency typically affects infants in the first year of life. The accumulation of fat in the walls of the gut in early onset disease leads to serious digestive problems including malabsorption, a condition in which the gut fails to absorb nutrients and calories from food. Because of these digestive complications, affecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholesteryl Ester Transfer Protein
Cholesteryl ester transfer protein (CETP), also called plasma lipid transfer protein, is a plasma protein that facilitates the transport of cholesteryl esters and triglycerides between the lipoproteins. It collects triglycerides from very-low-density (VLDL) or Chylomicrons and exchanges them for cholesteryl esters from high-density lipoproteins (HDL), and vice versa. Most of the time, however, CETP does a heteroexchange, trading a triglyceride for a cholesteryl ester or a cholesteryl ester for a triglyceride. Genetics The ''CETP'' gene is located on the sixteenth chromosome (16q21). Protein Fold The crystal structure of CETP is that of dimer of two TUbular LIPid (TULIP) binding domains. Each domain consists of a core of 6 elements: 4 beta-sheets forming an extended superhelix; 2 flanking elements that tend to include some alpha helix. The sheets wrap around the helices to produce a cylinder 6 x 2.5 x 2.5 nm. CETP contains two of these domains that interact head-to-head ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alzheimer’s Disease
Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation (including easily getting lost), mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the typical life expectancy following diagnosis is three to nine years. The cause of Alzheimer's disease is poorly understood. There are many environmental and genetic risk factors associated with its development. The strongest genetic risk factor is from an allele of APOE. Other risk factors include a history of head injury, clinical depression, and high blood pressu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Sclerosis
Multiple (cerebral) sclerosis (MS), also known as encephalomyelitis disseminata or disseminated sclerosis, is the most common demyelinating disease, in which the insulating covers of nerve cells in the brain and spinal cord are damaged. This damage disrupts the ability of parts of the nervous system to transmit signals, resulting in a range of signs and symptoms, including physical, mental, and sometimes psychiatric problems. Specific symptoms can include double vision, blindness in one eye, muscle weakness, and trouble with sensation or coordination. MS takes several forms, with new symptoms either occurring in isolated attacks (relapsing forms) or building up over time (progressive forms). In the relapsing forms of MS, between attacks, symptoms may disappear completely, although some permanent neurological problems often remain, especially as the disease advances. While the cause is unclear, the underlying mechanism is thought to be either destruction by the immune system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to Motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in Fine motor skill, fine movement, Equilibrioception, equilibrium, Human positions, posture, and motor learning in humans. Anatomica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudate Nucleus
The caudate nucleus is one of the structures that make up the corpus striatum, which is a component of the basal ganglia in the human brain. While the caudate nucleus has long been associated with motor processes due to its role in Parkinson's disease, it plays important roles in various other nonmotor functions as well, including procedural learning, associative learning and inhibitory control of action, among other functions. The caudate is also one of the brain structures which compose the reward system and functions as part of the cortico–basal ganglia– thalamic loop. Structure Together with the putamen, the caudate forms the dorsal striatum, which is considered a single functional structure; anatomically, it is separated by a large white matter tract, the internal capsule, so it is sometimes also referred to as two structures: the medial dorsal striatum (the caudate) and the lateral dorsal striatum (the putamen). In this vein, the two are functionally distinct not a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid
Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing energy, signaling, and acting as structural components of cell membranes. Lipids have applications in the cosmetic and food industries, and in nanotechnology. Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, multilamellar/unilamellar liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huntington Disease
Huntington's disease (HD), also known as Huntington's chorea, is a neurodegenerative disease that is mostly inherited. The earliest symptoms are often subtle problems with mood or mental abilities. A general lack of coordination and an unsteady gait often follow. It is also a basal ganglia disease causing a hyperkinetic movement disorder known as chorea. As the disease advances, uncoordinated, involuntary body movements of chorea become more apparent. Physical abilities gradually worsen until coordinated movement becomes difficult and the person is unable to talk. Mental abilities generally decline into dementia. The specific symptoms vary somewhat between people. Symptoms usually begin between 30 and 50 years of age but can start at any age. The disease may develop earlier in each successive generation. About eight percent of cases start before the age of 20 years, and are known as ''juvenile HD'', which typically present with the slow movement symptoms of Parkinson's di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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