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Adrenal Androgen-stimulating Hormone
Adrenal androgen stimulating hormone (AASH), also known as cortical androgen stimulating hormone (CASH), is a hypothetical hormone which has been proposed to stimulate the adrenal glands to produce adrenal androgens such as dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and androstenedione (A4). It is hypothesized to be involved in adrenarche and adrenopause. The existence of this hormone is controversial and disputed and it has not been identified to date. A number of other mechanisms and/or hormones may instead play the functional role of the so-called AASH. See also * Adrenocorticotrophic hormone Adrenocorticotropic hormone (ACTH; also adrenocorticotropin, corticotropin) is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important c ... (ACTH) References {{Biochemistry-stub Biochemistry Hormones Adrenal gland ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 for the correct development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Among the substances that can be considered hormones, are eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organs and tissues. In vertebrates, hormones are responsible for regulating a variety of physiological processes and behavioral activities such as diges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenal Gland
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which produces steroid hormones and an inner medulla. The adrenal cortex itself is divided into three main zones: the zona glomerulosa, the zona fasciculata and the zona reticularis. The adrenal cortex produces three main types of steroid hormones: mineralocorticoids, glucocorticoids, and androgens. Mineralocorticoids (such as aldosterone) produced in the zona glomerulosa help in the regulation of blood pressure and electrolyte balance. The glucocorticoids cortisol and cortisone are synthesized in the zona fasciculata; their functions include the regulation of metabolism and immune system suppression. The innermost layer of the cortex, the zona reticularis, produces androgens that are converted to fully functional sex hormones in the gonads ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenal Androgen
Adrenal steroids are steroids that are derived from the adrenal glands. They include corticosteroids, which consist of glucocorticoids like cortisol and mineralocorticoids like aldosterone, adrenal androgens like dehydroepiandrosterone (DHEA), DHEA sulfate (DHEA-S), and androstenedione (A4), and neurosteroids like DHEA and DHEA-S, as well as pregnenolone and pregnenolone sulfate (P5-S). Adrenal steroids are specifically produced in the adrenal cortex. Adrenal steroids are distinguished from ''gonadal steroids'', which are steroids that are derived from the gonads and include sex steroids such as progestogens like progesterone, potent androgens like testosterone, and estrogens like estradiol. Function The main role of adrenal steroids is to regulate electrolyte and water levels in the kidneys. Each steroid has a different effect on these levels. These effects also depend on the functionality of the adrenal glands. In people with adrenal insufficiency, desoxycorticosterone acts to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydroepiandrosterone
Dehydroepiandrosterone (DHEA), also known as androstenolone, is an endogenous steroid hormone precursor. It is one of the most abundant circulating steroids in humans. DHEA is produced in the adrenal glands, the gonads, and the brain. It functions as a metabolic intermediate in the biosynthesis of the androgen and estrogen sex steroids both in the gonads and in various other tissues. However, DHEA also has a variety of potential biological effects in its own right, binding to an array of nuclear and cell surface receptors, and acting as a neurosteroid and modulator of neurotrophic factor receptors. In the United States, DHEA is sold as an over-the-counter supplement, and medication called prasterone. Biological function As an androgen DHEA and other adrenal androgens such as androstenedione, although relatively weak androgens, are responsible for the androgenic effects of adrenarche, such as early pubic and axillary hair growth, adult-type body odor, increased oiliness of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehydroepiandrosterone Sulfate
Dehydroepiandrosterone sulfate, abbreviated as DHEA sulfate or DHEA-S, also known as androstenolone sulfate, is an endogenous androstane steroid that is produced by the adrenal cortex. It is the 3β-sulfate ester and a metabolite of dehydroepiandrosterone (DHEA) and circulates in far greater relative concentrations than DHEA. The steroid is hormonally inert and is instead an important neurosteroid and neurotrophin. Biological activity Neurosteroid activity Similarly to other conjugated steroids, DHEA-S is devoid of hormonal activity, lacking affinity for the steroid hormone receptors. However, DHEA-S retains activity as a neurosteroid and neurotrophin. It has been found to act as a positive allosteric modulator of the NMDA receptor (50 nM–1 μM), negative allosteric modulator of the GABAA and glycine receptors, and weak agonist of the sigma-1 receptor (Kd > 50 μM). In addition, DHEA-S has been found to directly bind to and activate the TrkA and p75NT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androstenedione
Androstenedione, or 4-androstenedione (abbreviated as A4 or Δ4-dione), also known as androst-4-ene-3,17-dione, is an endogenous weak androgen steroid hormone and intermediate in the biosynthesis of estrone and of testosterone from dehydroepiandrosterone (DHEA). It is closely related to androstenediol (androst-5-ene-3β,17β-diol). Biological function Androstenedione is a precursor of testosterone and other androgens, as well as of estrogens like estrone, in the body. In addition to functioning as an endogenous prohormone, androstenedione also has weak androgenic activity in its own right. Androstenedione has been found to possess some estrogenic activity, similarly to other DHEA metabolites. However, in contrast to androstenediol, its affinity for the estrogen receptors is very low, with less than 0.01% of the affinity of estradiol for both the ERα and ERβ. Adrenarche In children aged 6 to 8 years old, there is a rise in androstenedione secretion along with DHEA during adr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenarche
Adrenarche is an early stage in sexual maturation that happens in some higher primates and in humans, typically peaks at around 20 years of age, and is involved in the development of pubic hair, body odor, skin oiliness, axillary hair, sexual attraction/sexual desire/increased libido and mild acne. During adrenarche the adrenal glands secrete increased levels of weak adrenal androgens, including dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and androstenedione (A4), but without increased cortisol levels. Adrenarche is the result of the development of a new zone of the adrenal cortex, the zona reticularis. Adrenarche is a process related to puberty, but distinct from hypothalamic–pituitary–gonadal axis (HPG axis) maturation and function. Occurrence Adrenarche occurs starting at the age of 6 years. After the first year of life, the adrenal glands secrete very low levels of adrenal androgens. Adrenarche begins on average between age 5 to 8& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenopause
Adrenopause is the decline in secretion and levels of adrenal androgens such as dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) from the zona reticularis of the adrenal glands with age. Levels of adrenal androgens start to increase around age 7 or 8 years (adrenarche), peak in early adulthood around age 20 to 25 years, and decrease at a rate of approximately 2% per year thereafter, eventually reaching levels of 10 to 20% of those of young adults by age 80 years. It is caused by the progressive apoptosis of adrenal androgen-secreting cell (biology), cells and hence involution (medicine), involution of the zona reticularis. It is analogous to andropause in men and menopause in women, the abrupt or gradual decline in production of sex hormones from the gonads with age. DHEA can be dietary supplement, supplemented or taken as a medication in the form of prasterone to replace adrenal androgens later in life if it is desired. Some clinical studi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adrenocorticotrophic Hormone
Adrenocorticotropic hormone (ACTH; also adrenocorticotropin, corticotropin) is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress (along with its precursor corticotropin-releasing hormone from the hypothalamus). Its principal effects are increased production and release of cortisol by the cortex of the adrenal gland. ACTH is also related to the circadian rhythm in many organisms. Deficiency of ACTH is an indicator of secondary adrenal insufficiency (suppressed production of ACTH due to an impairment of the pituitary gland or hypothalamus, cf. hypopituitarism) or tertiary adrenal insufficiency (disease of the hypothalamus, with a decrease in the release of corticotropin releasing hormone (CRH)). Conversely, chronically elevated ACTH levels occur in primary a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research. Voet (2005), p. 3. Biochemistry focuses on understanding the chemical basis which allows biological molecules to give rise to the processes that occur within living cells and between cells,Karp (2009), p. 2. in turn relating greatly to the understanding of tissues and organs, as well as organism structure and function.Miller (2012). p. 62. Biochemistry is closely related to molecular biology, which is the study of the molecular mechanisms of biological phenomena.As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormones
A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required for the correct development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Among the substances that can be considered hormones, are eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. Estrogen, oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organ (anatomy), organs and Tissue (biology), tissues. In vertebrates, hormones are responsible for regulating a variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
