20-Hydroxyecdysone (ecdysterone or 20E) is a naturally occurring

ecdysteroid Ecdysteroids are arthropod steroid hormones that are mainly responsible for molting, development and, to a lesser extent, reproduction; examples of ecdysteroids include ecdysone, ecdysterone, turkesterone and 2-deoxyecdysone. These compounds are ...

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required ...

which controls the

ecdysis Ecdysis is the moulting of the cuticle in many invertebrates of the clade Ecdysozoa. Since the cuticle of these animals typically forms a largely inelastic exoskeleton, it is shed during growth and a new, larger covering is formed. The remnan ...

(moulting) and

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

arthropods Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and cuticle made of chitin, ...

. It is therefore one of the most common moulting hormones in insects, crabs, etc. It is also a phytoecdysteroid produced by various plants, including ''Cyanotis vaga'', ''

Ajuga turkestanica ''Ajuga turkestanica'' is a herbaceous flowering plant native to Central Asia. It was first described in 1894. Description ''A. turkestanica'' is a perennial herbaceous plant reaching heights between 40 and 60 cm. The plant is typically found ...

'' and ''Rhaponticum carthamoides'' where its purpose is presumably to disrupt the

development Development or developing may refer to: Arts *Development hell, when a project is stuck in development *Filmmaking, development phase, including finance and budgeting *Development (music), the process thematic material is reshaped * Photograph ...

and

reproduction Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. Reproduction is a fundamental feature of all known life; each individual or ...

of insect pests. In arthropods, 20-hydroxyecdysone acts through the ecdysone receptor. Although mammals lack this

receptor Receptor may refer to: *Sensory receptor, in physiology, any structure which, on receiving environmental stimuli, produces an informative nerve impulse *Receptor (biochemistry), in biochemistry, a protein molecule that receives and responds to a n ...

, 20-hydroxyecdysone may affect

mammalian Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fu ...

(including

human Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...

) biological systems ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology a ...

'', but there is uncertainty whether any ''

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and p ...

'' or physiological effects occur. 20-Hydroxyecdysone is an ingredient of some supplements that aim to enhance physical performance. In humans, it is hypothesized to bind to the

estrogen receptor beta Estrogen receptor beta (ERβ) also known as NR3A2 (nuclear receptor subfamily 3, group A, member 2) is one of two main types of estrogen receptor—a nuclear receptor which is activated by the sex hormone estrogen. In humans ERβ is encoded by ...

(ERβ) protein-coding gene.

Sources in arthropods

The primary sources of 20-hydroxyecdysone in larvae are the prothoracic gland, ring gland, gut, and fat bodies. These tissues convert dietary

cholesterol 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 memb ...

into the mature forms of the hormone 20-hydroxyecdysone. For the most part these glandular tissues are lost in the adult with exception of the fat body, which is retained as a sheath of lipid tissue surrounding the brain and organs of the abdomen. In the adult female the ovary is a substantial source of 20-hydroxyecdysone production. Adult males are left with, so far as is currently known, one source of 20-hydroxyecdysone which is the fat body tissue. These hormone producing tissues express the ecdysone receptor throughout development, possibly indicating a functional feedback mechanism.

Ecdysteroid activity in arthropods

is a type of steroid hormones in insects that are derived from enzymatic modification of cholesterol by

p450 Cytochromes P450 (CYPs) are a superfamily of enzymes containing heme as a cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance of various compo ...

enzymes. This occurs by a mechanism similar to

steroid synthesis 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 that alter membrane fluidity; and ...

in vertebrates.

Ecdysone Ecdysone is a prohormone of the major insect molting hormone 20-hydroxyecdysone, which is secreted from the prothoracic glands. It is of steroidal structure. Insect molting hormones (ecdysone and its homologues) are generally called ecdysteroids. E ...

and 20-hydroxyecdysone regulate larval molts, onset of puparium formation, and metamorphosis. Being that these hormones are hydrophobic, they traverse lipid membranes and permeate the tissues of an organism. Indeed, the main receptor of these hormone signals - the ecdysone receptor - is an

intracellular This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions ...

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

In humans and other mammals

Use as supplement

20-Hydroxyecdysone and other ecdysteroids are marketed as ingredients in nutritional supplements for various sports, particularly

bodybuilding Bodybuilding is the use of progressive resistance exercise to control and develop one's muscles (muscle building) by muscle hypertrophy for aesthetic purposes. It is distinct from similar activities such as powerlifting because it focuses ...

. A comprehensive study, designed to find any strength or athletic improvement from 20-hydroxyecdysone, was published in 2006. The study looked for improvement in actual exercises performed and tested for improvements/increases in chemical indicators such as body composition and free/available testosterone. The results of the 2006 study concluded that using 30 mg per day of 20-hydroxyecdysone administered orally did not significantly affect anabolic or catabolic responses to resistance training, body composition, or training adaptations. However, a number of earlier studies (,) supported the anabolic effects of 20-Hydroxyecdysone. A more recent study conducted in 2019 by a team that included the Department for Molecular and Cellular Sports Medicine at the

German Sport University Cologne German Sport University Cologne (German: Deutsche Sporthochschule Köln, DSHS, Spoho), is a sport university in Cologne, Germany. History The Sport University Cologne was founded in 1947. After the Sport University had changed its name to "G ...

, found that significantly higher increases in muscle mass were observed in participants dosed with ecdysterone, with significantly more pronounced increases in one-repetition bench press performance. The study was funded by the

World Anti-Doping Agency The World Anti-Doping Agency (WADA; french: Agence mondiale antidopage, AMA) is a foundation initiated by the International Olympic Committee based in Canada to promote, coordinate, and monitor the fight against drugs in sports. The agency's key ...

(WADA) and demonstrated a significant dose-responsive anabolic effect of 20-Hydroxyecdysone supplementation on athletes during resistance training. Furthermore, recent studies () have elucidated that the mechanism of action of 20-Hydroxyecdysone on human muscle cells is relatively selective activation of the beta form of the estrogen receptor (ERβ), which is known to result in muscle hypertrophy.

Use as research tool

20-Hydroxyecdysone and other ecdysteroids are used in biochemistry research as inducers in transgenic animals, whereby a new gene is introduced into an animal so that its expression is under the control of an introduced ecdysone receptor. Adding or removing ecdysteroids from the animal's diet then gives a convenient way to turn the inserted gene on or off (see ecdysone receptor). At usual doses, 20-hydroxyecdysone appears to have little or no effect on animals that do not have extra genes inserted; it also has high bioavailability when taken orally, so it is useful for determining whether the transgene has been taken up effectively. For uses in

gene therapy Gene therapy is a Medicine, medical field which focuses on the genetic modification of cells to produce a therapeutic effect or the treatment of disease by repairing or reconstructing defective genetic material. The first attempt at modifying ...

, it may be necessary to investigate more thoroughly the natural sources of ecdysteroids in humans (which appear to include

dietary In nutrition, diet is the sum of food consumed by a person or other organism. The word diet often implies the use of specific intake of nutrition for health or weight-management reasons (with the two often being related). Although humans are o ...

phytoecdysteroids,

gut flora Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut m ...

helminth Parasitic worms, also known as helminths, are large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as ...

infections An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable di ...

, and other

diseases A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...

External links

Ecdybase
The Ecdysone Handbook - a free online ecdysteroids database

References

{{DEFAULTSORT:Hydroxyecdysone, 20- Insect hormones Primary alcohols Sterols Tertiary alcohols