- Lipid metabolism is the synthesis and degradation of lipids in cells, involving the breakdown or storage of fats for energy and the synthesis of structural and functional lipids, such as those involved in the construction of cell membranes. In animals, these fats are obtained from food or are synthesized by the liver.
- beta-oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl-CoA, which enters the citric acid cycle, and NADH and FADH2, which are co-enzymes used in the electron transport chain. It is named as such because the beta carbon of the fatty acid undergoes oxidation to a carbonyl group. Beta-oxidation is primarily facilitated by the mitochondrial trifunctional protein, an enzyme complex associated with the inner mitochondrial membrane, although very long chain fatty acids are oxidized in peroxisomes.
- Acyl-CoA is a group of coenzymes that metabolize fatty acids. Acyl-CoA’s are susceptible beta oxidation, forming, ultimately, acetyl-CoA. The acetyl-CoA enters the citric acid cycle, eventually forming several equivalents of ATP.
- Carnitine is a quaternary ammonium compound involved in metabolism in most mammals, plants and some bacteria. Carnitine may exist in two isomers, labeled D-carnitine and L-carnitine, which are both biologically active.
Nicotinamide Adenine Dinucleotide
- Nicotinamide adenine dinucleotide is a cofactor that is central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine nucleobase and the other nicotinamide.
- Thiolases, also known as acetyl-coenzyme A acetyltransferases, are enzymes which convert two units of acetyl-CoA to acetoacetyl CoA in the mevalonate pathway.
Fatty Acid Oxidation
- Fatty acid oxidation is the mitochondrial aerobic process of breaking down a fatty acid into acetyl-CoA units
- A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes which alter membrane fluidity; and as signaling molecules.
- Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Different molecular forms of bile acids can be synthesized in the liver by different species.
- The mevalonate pathway, also known as the isoprenoid pathway or HMG-CoA reductase pathway is an essential metabolic pathway present in eukaryotes, archaea, and some bacteria.
- Ketone bodies are the water-soluble molecules containing the ketone group that are produced by the liver from fatty acids during periods of low food intake, carbohydrate restrictive diets, starvation, prolonged intense exercise, alcoholism or in untreated type 1 diabetes mellitus.
- Acetoacetate is a 3-oxo monocarboxylic acid anion that is the conjugate base of acetoacetic acid, arising from deprotonation of the carboxy group. It has a role as a human metabolite. It derives from a butyrate. It is a conjugate base of an acetoacetic acid.
- Isoprenoid, any of a class of organic compounds composed of two or more units of hydrocarbons, with each unit consisting of five carbon atoms arranged in a specific pattern. Isoprenoids play widely varying roles in the physiological processes of plants and animals. They also have a number of commercial uses.
- Lanosterol is a tetracyclic triterpenoid and is the compound from which all animal and fungal steroids are derived. By contrast plant steroids are produced via cycloartenol.
- Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, although plant sources are now used as well, including amaranth seed, rice bran, wheat germ, and olives.
- Farnesyl pyrophosphate, also known as farnesyl diphosphate, is an intermediate in both the mevalonate and non-mevalonate pathways used by organisms in the biosynthesis of terpenes, terpenoids, and sterols.
- Geranyl pyrophosphate, also known as geranyl diphosphate, is an intermediate in the HMG-CoA reductase pathway used by organisms in the biosynthesis of farnesyl pyrophosphate, geranylgeranyl pyrophosphate. These species are respectively precursors to sesquiterpenes and diterpenes.
- Chylomicrons are lipoprotein particles that consist of triglycerides, phospholipids, cholesterol, and proteins. Due to their density relative to lipoproteins, they are also commonly known as ultra low density lipoproteins in modern usage.
- Connective tissue composed of adipocytes. Its main role is to store energy in the form of fat, although it also cushions and insulates the body.
- Receptor-mediated endocytosis, also called clathrin-mediated endocytosis, is a process by which cells absorb metabolites, hormones, proteins – and in some cases viruses – by the inward budding of the plasma membrane.
- A steroid hormone is a steroid that acts as a hormone. Steroid hormones can be grouped into two classes: corticosteroids and sex steroids. Within those two classes are five types according to the receptors to which they bind: glucocorticoids, mineralocorticoids, androgens, estrogens, and progestogens.
- Cholic acid, also known as 3α,7α,12α-trihydroxy-5β-cholan-24-oic acid is a primary bile acid that is insoluble in water, it is a white crystalline substance. Salts of cholic acid are called cholates.
- Deoxycholic acid, also known as cholanoic acid, Kybella, Celluform Plus, Belkyra, and 3α,12α-dihydroxy-5β-cholan-24-oic acid, is a bile acid. Deoxycholic acid is one of the secondary bile acids, which are metabolic byproducts of intestinal bacteria.
- Taurocholic acid, known also as cholaic acid, cholyltaurine, or acidum cholatauricum, is a deliquescent yellowish crystalline bile acid involved in the emulsification of fats. It occurs as a sodium salt in the bile of mammals. It is a conjugate of cholic acid with taurine.
- Inositol, or more precisely myo-inositol, is a carbocyclic sugar that is abundant in brain and other mammalian tissues, mediates cell signal transduction in response to a variety of hormones, neurotransmitters and growth factors and participates in osmoregulation.
- Sphingolipids are a class of lipids containing a backbone of sphingoid bases, a set of aliphatic amino alcohols that includes sphingosine. They were discovered in brain extracts in the 1870s and were named after the mythological sphinx because of their enigmatic nature.
- Sphingosine is an 18-carbon amino alcohol with an unsaturated hydrocarbon chain, which forms a primary part of sphingolipids, a class of cell membrane lipids that include sphingomyelin, an important phospholipid.
- Sphingomyelin is a type of sphingolipid found in animal cell membranes, especially in the membranous myelin sheath that surrounds some nerve cell axons. It usually consists of phosphocholine and ceramide, or a phosphoethanolamine head group; therefore, sphingomyelins can also be classified as sphingophospholipids
- Cerebrosides is the common name for a group of glycosphingolipids called monoglycosylceramides which are important components in animal muscle and nerve cell membranes. They consist of a ceramide with a single sugar residue at the 1-hydroxyl moiety.
- A ganglioside is a molecule composed of a glycosphingolipid (ceramide and oligosaccharide) with one or more sialic acids (e.g. n-acetylneuraminic acid, NANA) linked on the sugar chain.