|
20α-dihydroprogesterone
20α-Dihydroprogesterone (20α-DHP), also known as 20α-hydroxyprogesterone (20α-OHP), is a naturally occurring, endogenous progestogen. It is a metabolite of progesterone, formed by the 20α-hydroxysteroid dehydrogenases (20α-HSDs) AKR1C1, AKR1C2, and AKR1C3 and the 17β-hydroxysteroid dehydrogenase (17β-HSD) HSD17B1. 20α-DHP can be transformed back into progesterone by 20α-HSDs and by the 17β-HSD HSD17B2. HSD17B2 is expressed in the human endometrium and cervix among other tissues. In animal studies, 20α-DHP has been found to be selectively taken up into and retained in target tissues such as the uterus, brain, and skeletal muscle. 20α-DHP has very low affinity for the progesterone receptor and is much less potent as a progestogen in comparison to progesterone, with about one-fifth of the relative progestogenic activity. It has also been found to act as an aromatase inhibitor and to inhibit the production of estrogen in breast tissue ''in vitro''. A single 200-mg ora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progesterone
Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the major progestogen in the body. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroids, including the sex hormones and the corticosteroids, and plays an important role in brain function as a neurosteroid. In addition to its role as a natural hormone, progesterone is also used as a medication, such as in combination with estrogen for contraception, to reduce the risk of uterine or cervical cancer, in hormone replacement therapy, and in feminizing hormone therapy. It was first prescribed in 1934. Biological activity Progesterone is the most important progestogen in the body. As a potent agonist of the nuclear progesterone receptor (nPR) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progestogen
Progestogens, also sometimes written progestagens or gestagens, are a class of natural or synthetic steroid hormones that bind to and activate the progesterone receptors (PR). Progesterone is the major and most important progestogen in the body. The progestogens are named for their function in maintaining pregnancy (i.e., ''progestational''), although they are also present at other phases of the estrous and menstrual cycles. The progestogens are one of three types of sex hormones, the others being estrogens like estradiol and androgens/anabolic steroids like testosterone. In addition, they are one of the five major classes of steroid hormones, the others being the androgens, estrogens, glucocorticoids, and mineralocorticoids, as well as the neurosteroids. All endogenous progestogens are characterized by their basic 21-carbon skeleton, called a pregnane skeleton (C21). In similar manner, the estrogens possess an estrane skeleton (C18), and androgens, an androstane skeleton (C19). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Product
A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical synthesis (both semisynthesis and total synthesis) and have played a central role in the development of the field of organic chemistry by providing challenging synthetic targets. The term natural product has also been extended for commercial purposes to refer to cosmetics, dietary supplements, and foods produced from natural sources without added artificial ingredients. Within the field of organic chemistry, the definition of natural products is usually restricted to organic compounds isolated from natural sources that are produced by the pathways of primary or secondary metabolism. Within the field of medicinal chemistry, the definition is often further restricted to secondary metabolites. Secondary metabolites (or specialized metabolites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Affinity (pharmacology)
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from ''ligare'', which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure. Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition of liga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
11-Deoxycorticosterone
11-Deoxycorticosterone (DOC), or simply deoxycorticosterone, also known as 21-hydroxyprogesterone, as well as desoxycortone (INN), deoxycortone, and cortexone, is a steroid hormone produced by the adrenal gland that possesses mineralocorticoid activity and acts as a precursor to aldosterone. It is an active (Na+-retaining) mineralocorticoid. As its names indicate, can be understood as the 21- hydroxy-variant of progesterone or as the 11-deoxy-variant of corticosterone. ''DOCA'' is the abbreviation for the ester 11-deoxycorticosterone acetate. Biological activity DOC is a potent mineralocorticoid but is virtually devoid of glucocorticoid activity. However, 11β-hydroxylation of DOC produces corticosterone and confers glucocorticoid activity, along with 10-fold reduced mineralocorticoid activity. In addition to its mineralocorticoid activity, DOC has been found to possess one-third to one-tenth the potency of progesterone as a progestogen when administered systematically to r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-Dihydroprogesterone
5α-Dihydroprogesterone (5α-DHP, allopregnanedione, or 5α-pregnane-3,20-dione) is an endogenous progestogen and neurosteroid that is synthesized from progesterone. It is also an intermediate in the synthesis of allopregnanolone and isopregnanolone from progesterone. 5α-DHP is metabolized by the aldo-keto reductases (AKRs) AKR1C1, AKR1C2, and AKR1C4 with high catalytic efficiency. AKR1C1 preferentially forms 20α-hydroxy-5α-pregnane-3-one while AKR1C2 preferentially forms allopregnanolone. Similarly AKR1C1 reduces and consequently inactivates allopregnanolone into 5α-pregnane-3α,20α-diol. In contrast to the other AKRs, AKR1C3 has low catalytic efficiency for reduction of 5α-DHP. These AKRs are highly expressed in the human liver and mammary gland but have relatively modest expression in the human brain and uterus. 5α-DHP is an agonist of the progesterone receptor and a positive allosteric modulator of the GABAA receptor (albeit with an affinity for this receptor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
16α-Hydroxyprogesterone
16α-Hydroxyprogesterone (16α-OHP), also known as 16α-hydroxypregn-4-ene-3,20-dione, is a minor endogenous progestogen steroid hormone and a metabolite of progesterone that is formed in lower amounts than 17α-hydroxyprogesterone (17α-OHP). It occurs in micromolar concentrations and its physiological relevance hence is questionable. However, it may accumulate in target tissues and could have a physiological role in the reproductive system and mammary gland development as well as the cardiovascular and central nervous systems. 16α-OHP is formed from progesterone via 16α- hydroxylation primarily by CYP17A1 and primarily in steroidogenic tissues including the adrenal glands, testes, and ovaries. It is also synthesized from progesterone during pregnancy by hepatic cytochrome P450 enzymes like CYP3A4 and CYP1A1 in the fetal liver as well as placenta. It appears to be an end metabolite of progesterone and does not seem to be further metabolized. 16α-OHP has approximately ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
17α-Hydroxyprogesterone
17α-Hydroxyprogesterone (17α-OHP), also known as 17-OH progesterone (17-OHP), or hydroxyprogesterone (OHP), is an endogenous progestogen steroid hormone related to progesterone. It is also a chemical intermediate in the biosynthesis of many other endogenous steroids, including androgens, estrogens, glucocorticoids, and mineralocorticoids, as well as neurosteroids. Biological activity 17α-OHP is an agonist of the progesterone receptor (PR) similarly to progesterone, albeit weakly in comparison. In addition, it is an antagonist of the mineralocorticoid receptor (MR) as well as a partial agonist of the glucocorticoid receptor (GR), albeit with very low potency ( EC50 >100-fold less relative to cortisol) at the latter site, also similarly to progesterone. Biochemistry Biosynthesis 17α-OHP is derived from progesterone via 17α-hydroxylase (encoded by CYP17A1) 17α-OHP increases in the third trimester of pregnancy primarily due to fetal adrenal production. This steroid is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
20β-Dihydroprogesterone
20β-Dihydroprogesterone (20β-DHP), also known as 20β-hydroxyprogesterone (20β-OHP), is an endogenous metabolite of progesterone which is formed by 20β-hydroxysteroid dehydrogenase (20β-HSD). It is a progestogen similarly to progesterone, with about 20 to 50% of the progestogenic activity of progesterone. It can be converted by 20β-HSD into progesterone in the uterus. The effects of 20β-HSD on the uterus, mammary glands, and in maintaining pregnancy have been studied. The progestogenic activity of 20β-HSD has also been characterized in women. See also * 20α-Dihydroprogesterone * 17α-Hydroxyprogesterone * 16α-Hydroxyprogesterone * 5α-Dihydroprogesterone * 11-Deoxycorticosterone 11-Deoxycorticosterone (DOC), or simply deoxycorticosterone, also known as 21-hydroxyprogesterone, as well as desoxycortone (INN), deoxycortone, and cortexone, is a steroid hormone produced by the adrenal gland that possesses mineralocorticoid ac ... References Secondary alcohols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver
The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it is located in the quadrant (anatomy), right upper quadrant of the abdomen, below the thoracic diaphragm, diaphragm. Its other roles in metabolism include the regulation of Glycogen, glycogen storage, decomposition of red blood cells, and the production of hormones. The liver is an accessory digestive organ that produces bile, an alkaline fluid containing cholesterol and bile acids, which helps the fatty acid degradation, breakdown of fat. The gallbladder, a small pouch that sits just under the liver, stores bile produced by the liver which is later moved to the small intestine to complete digestion. The liver's highly specialized biological tissue, tissue, consisting mostly of hepatocytes, regulates a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 and its subdisciplines are traditionally done in labware such as test tubes, flasks, Petri dishes, and microtiter plates. Studies conducted using components of an organism that have been isolated from their usual biological surroundings permit a more detailed or more convenient analysis than can be done with whole organisms; however, results obtained from ''in vitro'' experiments may not fully or accurately predict the effects on a whole organism. In contrast to ''in vitro'' experiments, ''in vivo'' studies are those conducted in living organisms, including humans, and whole plants. Definition ''In vitro'' ( la, in glass; often not italicized in English usage) studies are conducted using components of an organism that have been isolated fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breast
The breast is one of two prominences located on the upper ventral region of a primate's torso. Both females and males develop breasts from the same embryological tissues. In females, it serves as the mammary gland, which produces and secretes milk to feed infants. Subcutaneous fat covers and envelops a network of ducts that converge on the nipple, and these tissues give the breast its size and shape. At the ends of the ducts are lobules, or clusters of alveoli, where milk is produced and stored in response to hormonal signals. During pregnancy, the breast responds to a complex interaction of hormones, including estrogens, progesterone, and prolactin, that mediate the completion of its development, namely lobuloalveolar maturation, in preparation of lactation and breastfeeding. Humans are the only animals with permanent breasts. At puberty, estrogens, in conjunction with growth hormone, cause permanent breast growth in female humans. This happens only to a much lesser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
