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Corticoid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involved in a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. Some common naturally occurring steroid hormones are cortisol (), corticosterone (), cortisone () and aldosterone () (cortisone and aldosterone are isomers). The main corticosteroids produced by the adrenal cortex are cortisol and aldosterone. The etymology of the '' cortico-'' part of the name refers to the adrenal cortex, which makes these steroid hormones. Thus a corticosteroid is a "cortex steroid". Classes * Glucocorticoids such as cortisol affect carbohydrate, fat, and protein metabolism, and have anti-inflammatory, immuno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucocorticoid
Glucocorticoids (or, less commonly, glucocorticosteroids) are a class of corticosteroids, which are a class of steroid hormones. Glucocorticoids are corticosteroids that bind to the glucocorticoid receptor that is present in almost every vertebrate animal cell. The name "glucocorticoid" is a portmanteau of "glucose", "cortex", and "steroid" and is composed from its role in regulation of glucose metabolism, synthesis in the adrenal cortex, and its steroidal structure (see structure below). Glucocorticoids are part of the feedback mechanism in the immune system, which reduces certain aspects of immune function, such as inflammation. They are therefore used in medicine to treat diseases caused by an Autoimmunity, overactive immune system, such as Allergy, allergies, asthma, autoimmune diseases, and sepsis. Glucocorticoids have many Side effect, diverse effects such as pleiotropy (drugs), pleiotropy, including Adverse drug reaction, potentially harmful side effects. They also interfer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucocorticoid Receptor
The glucocorticoid receptor (GR or GCR) also known by its gene name ''NR3C1'' ( nuclear receptor subfamily 3, group C, member 1) is the steroid receptor for glucocorticoids such as cortisol. The GR is expressed in almost every cell in the body and regulates genes controlling the development, metabolism, inflammation, and immune response. Because the receptor gene is expressed in several forms, it has many different ( pleiotropic) effects in different parts of the body and in the context of different diseases. GR is a steroid receptor and thus its canonical action is similar to other steroid receptors. ree full text/ref> The unbound receptor resides in the cytosol of the cell. When glucocorticoids bind to the receptor, GR translocates to the nucleus of the cell where it acts as a transcription factor. The activated GR complex up-regulates the expression of anti-inflammatory proteins in the nucleus or represses the expression of pro-inflammatory proteins in the cytosol (by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineralocorticoid Receptor
The mineralocorticoid receptor (or MR, MLR, MCR), also known as the aldosterone receptor or nuclear receptor subfamily 3, group C, member 2, (NR3C2) is a protein that in humans is encoded by the ''NR3C2'' gene that is located on chromosome 4q31.1-31.2. MR is a receptor with equal affinity for mineralocorticoids and glucocorticoids. It belongs to the nuclear receptor family where the ligand diffuses into cells, interacts with the receptor and results in a signal transduction affecting specific gene expression in the nucleus. The selective response of some tissues and organs to mineralocorticoids over glucocorticoids occurs because mineralocorticoid-responsive cells express Corticosteroid 11-beta-dehydrogenase isozyme 2, an enzyme which selectively inactivates glucocorticoids more readily than mineralocorticoids. Function MR is expressed in many tissues, such as the kidney, colon, heart, central nervous system (hippocampus), brown adipose tissue and sweat glands. In epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineralocorticoid
Mineralocorticoids are a class of corticosteroids, which in turn are a class of steroid hormones. Mineralocorticoids are produced in the adrenal cortex and influence salt and water balances (electrolyte balance and fluid balance). The primary mineralocorticoid is aldosterone. Physiology The name mineralocorticoid derives from early observations that these hormones were involved in the retention of sodium, a mineral. The primary endogenous mineralocorticoid is aldosterone, although a number of other endogenous hormones (including progesterone and deoxycorticosterone) have mineralocorticoid function. Aldosterone acts on the kidneys to provide active reabsorption of sodium and an associated passive reabsorption of water, as well as the active secretion of potassium in the principal cells of the cortical collecting tubule and active secretion of protons via proton ATPases in the lumenal membrane of the intercalated cells of the collecting tubule. This in turn results in an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cortisol
Cortisol is a steroid hormone in the glucocorticoid class of hormones and a stress hormone. When used as medication, it is known as hydrocortisone. Cortisol is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in an adrenal gland. In other tissues, it is produced in lower quantities. By a Circadian rhythm, diurnal cycle, cortisol is released and increases in response to Stress (biology), stress and a low Blood sugar, blood-glucose concentration. It functions to increase blood sugar through gluconeogenesis, suppress the immune system, and aid in the metabolism of calories. It also decreases bone formation. These stated functions are carried out by cortisol binding to glucocorticoid or mineralocorticoid receptors inside a cell, which then bind to DNA to affect gene expression. Health effects Metabolic response Metabolism of glucose Cortisol plays a crucial role in regulating glucose metabolism and promotes gluconeogenesis (glucose synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldosterone
Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays a central role in the homeostatic regulation of blood pressure, plasma sodium (Na+), and potassium (K+) levels. It does so primarily by acting on the mineralocorticoid receptors in the distal tubules and collecting ducts of the nephron. It influences the reabsorption of sodium and excretion of potassium (from and into the tubular fluids, respectively) of the kidney, thereby indirectly influencing water retention or loss, blood pressure, and blood volume.Marieb Human Anatomy & Physiology 9th edition, chapter:16, page:629, question number:14 When dysregulated, aldosterone is pathogenic and contributes to the development and progression of cardiovascular and kidney disease. Aldosterone has exactly the opposite function of the atrial nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenal Cortex
The adrenal cortex is the outer region and also the largest part of the adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. It is also a secondary site of androgen synthesis. Layers The adrenal cortex comprises three main zones, or layers that are regulated by distinct hormones as noted below. This ''anatomic zonation'' can be appreciated at the microscopic level, where each zone can be recognized and distinguished from one another based on structural and anatomic characteristics. Zona glomerulosa The outermost layer, the zona glomerulosa is the main site for the production of aldosterone, a mineralocorticoid. The synthesis and secretion of aldosterone are mainly regulated by the renin–angiotensin–aldosterone system. The zona glomerulosa cells express a specific enzyme aldosterone synthase (also known as CYP11B2). Aldosterone is largely responsible ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocortisone
Hydrocortisone is the name for the hormone cortisol when supplied as a medication. It is a corticosteroid and works as an anti-inflammatory and by immune suppression. Uses include conditions such as adrenocortical insufficiency, adrenogenital syndrome, high blood calcium, thyroiditis, rheumatoid arthritis, dermatitis, asthma, and COPD. It is the treatment of choice for adrenocortical insufficiency. It can be given by mouth, topically, rectally or by injection. Stopping treatment after long-term use should be done slowly. Common side effects may include mood changes, increased appetite, hyperglycemia, hypertension, and edema (swelling). With long-term use, common side effects include osteoporosis, adrenal insufficiency, upset stomach, physical weakness, easy bruising, and candidiasis (yeast infections). It is unclear if it is safe for use during pregnancy. Hydrocortisone was patented in 1936 and approved for medical use in 1941. It is on the World Health Orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticosterone
Corticosterone, also known as 17-deoxycortisol and 11β,21-dihydroxyprogesterone, is a 21-carbon steroid hormone of the corticosteroid type produced in the cortex of the adrenal glands. In the very rare case of congenital adrenal hyperplasia due to 17α-hydroxylase deficiency cortisol production is blocked. Roles In many species, including amphibians, reptiles, rodents and birds, corticosterone is a main glucocorticoid, involved in regulation of energy, immune reactions, and stress responses. However, in humans, cortisol is the primary glucocorticoid that is produced primarily in the zona fasciculata of the adrenal cortex. Corticosterone has only weak glucocorticoid and mineralocorticoid potencies in humans and is important mainly as an intermediate in the steroidogenic pathway from pregnenolone to aldosterone. Corticosterone is converted to aldosterone by aldosterone synthase, found only in the mitochondria of glomerulosa cells. Glomerulosa cells are found in the zon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steroid
A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and as signal transduction, signaling molecules. Examples include the lipid cholesterol, sex hormones estradiol and testosterone, anabolic steroids, and the anti-inflammatory corticosteroid drug dexamethasone. Hundreds of steroids are found in Fungus, fungi, plants, and animals. All steroids are manufactured in cells from a sterols, sterol: Cholesterol, cholesterol (animals), lanosterol (opisthokonts), or cycloartenol (plants). All three of these molecules are produced via Cyclic compound, cyclization of the triterpene squalene. Structure The steroid nucleus (parent structure, core structure) is called gonane (cyclopentanoperhydrophenanthrene). It is typically composed of seventeen carbon atoms, bonded in fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
