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Androgen Backdoor Pathway
The androgen backdoor pathway is a collective name for all metabolic pathways where clinically relevant androgens are synthesized with roundabout of testosterone as an intermediate product. Initially described as pathway where 5α-reduction of 17α-hydroxyprogesterone ultimately leads to 5α-dihydrotestosterone, several other pathways have been since then discovered that lead to 11-oxyandrogens which are potent agonists of the androgen receptors. A backdoor pathway is an alternative to the conventional, canonical androgenic pathway that involves testosterone. Dihydrotestosterone The primary feature of the androgen backdoor pathway is that 17α-hydroxyprogesterone (17-OHP) can be 5α-reduced and finally converted to 5α-dihydrotestosterone (DHT) via an alternative route that bypasses the conventional intermediates androstenedione and testosterone. In mammals, this route is activated during normal prenatal development and leads to early male sexual differentiation. It was first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolic Pathway
In biochemistry, a metabolic pathway is a linked series of chemical reactions occurring within a cell. The reactants, products, and intermediates of an enzymatic reaction are known as metabolites, which are modified by a sequence of chemical reactions catalyzed by enzymes. In most cases of a metabolic pathway, the product of one enzyme acts as the substrate for the next. However, side products are considered waste and removed from the cell. These enzymes often require dietary minerals, vitamins, and other cofactors to function. Different metabolic pathways function based on the position within a eukaryotic cell and the significance of the pathway in the given compartment of the cell. For instance, the, electron transport chain, and oxidative phosphorylation all take place in the mitochondrial membrane. In contrast, glycolysis, pentose phosphate pathway, and fatty acid biosynthesis all occur in the cytosol of a cell. There are two types of metabolic pathways that are character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SRD5A1
3-Oxo-5α-steroid 4-dehydrogenase 1 is an enzyme that in humans is encoded by the ''SRD5A1'' gene. It is one of three forms of steroid 5α-reductase. Steroid 5α-reductase (EC 1.3.99.5) catalyzes, among other reactions, the conversion of testosterone into the more potent androgen, 5α-dihydrotestosterone (DHT). The ''SRD5A1'', '' SRD5A2'', and '' SRD5A3'' genes in humans all encode 5α-reductase isozymes. Function The 3-oxo-5α-steroid 4-dehydrogenase 1 enzyme is involved in bile acid biosynthesis, androgen and estrogen metabolism. For instance, the enzyme catalyzes the conversion of testosterone into the more potent androgen, 5α-dihydrotestosterone. It can also catalyze the conversion of progesterone, corticosterone or other steroids, to its corresponding 5α-3-oxo-steroids. This chemical reaction is called 5α-reduction, i.e. the reduction of the Δ5-4 double bond in steroids by catalyzing direct hydride transfer from NADPH to the carbon 5 position of the steroid substr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prostate Cancer
Prostate cancer is cancer of the prostate. Prostate cancer is the second most common cancerous tumor worldwide and is the fifth leading cause of cancer-related mortality among men. The prostate is a gland in the male reproductive system that surrounds the urethra just below the bladder. It is located in the hypogastric region of the abdomen. To give an idea of where it is located, the bladder is superior to the prostate gland as shown in the image The rectum is posterior in perspective to the prostate gland and the ischial tuberosity of the pelvic bone is inferior. Only those who have male reproductive organs are able to get prostate cancer. Most prostate cancers are slow growing. Cancerous cells may spread to other areas of the body, particularly the bones and lymph nodes. It may initially cause no symptoms. In later stages, symptoms include pain or difficulty urinating, blood in the urine, or pain in the pelvis or back. Benign prostatic hyperplasia may produce similar symptoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benign Prostatic Hyperplasia
Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss of bladder control. Complications can include urinary tract infections, bladder stones, and chronic kidney problems. The cause is unclear. Risk factors include a family history, obesity, type 2 diabetes, not enough exercise, and erectile dysfunction. Medications like pseudoephedrine, anticholinergics, and calcium channel blockers may worsen symptoms. The underlying mechanism involves the prostate pressing on the urethra and thereby making it difficult to pass urine out of the bladder. Diagnosis is typically based on symptoms and examination after ruling out other possible causes. Treatment options include lifestyle changes, medications, a number of procedures, and surgery. In those with mild symptoms, weight loss, exercise, and decre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polycystic Ovary Syndrome
Polycystic ovary syndrome, or PCOS, is the most common endocrine disorder in women of reproductive age. The syndrome is named after the characteristic cysts which may form on the ovaries, though it is important to note that this is a sign and not the underlying cause of the disorder. Women with PCOS may experience irregular menstrual periods, heavy periods, excess hair, acne, pelvic pain, difficulty getting pregnant, and patches of thick, darker, velvety skin. The primary characteristics of this syndrome include: hyperandrogenism, anovulation, insulin resistance, and neuroendocrine disruption. A review of the international evidence found that the prevalence of PCOS could be as high as 26% among some populations, though ranges between 4% and 18% are reported for general populations. Despite its high prevalence, the exact cause of PCOS remains uncertain and there is no known cure. Definition Two definitions are commonly used: * NIH : In 1990 a consensus workshop sponsore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
11-ketodihydrotestosterone
11-Ketodihydrotestosterone (11-KDHT), also known as 5α-androstan-17β-ol-3,11-dione, is an endogenous, naturally occurring steroid and androgen prohormone that is produced primarily, if not exclusively, in the adrenal glands. It is closely related to 11β-hydroxyandrostenedione (11β-KA4), adrenosterone (11-ketoandrostenedione; 11-KA4), and 11-ketotestosterone (11-KT), which are also produced in the adrenal glands. See also * Dihydrotestosterone Dihydrotestosterone (DHT, 5α-dihydrotestosterone, 5α-DHT, androstanolone or stanolone) is an endogenous androgen sex steroid and hormone. The enzyme 5α-reductase catalyzes the formation of DHT from testosterone in certain tissues includ ... References 5α-Reduced steroid metabolites Secondary alcohols Androgens and anabolic steroids Androstanes Hormones of the suprarenal cortex Ketones Sex hormones Steroid hormones {{steroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bond C=O). The simplest ketone is acetone (where R and R' is methyl), with the formula . Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids (e.g., testosterone), and the solvent acetone. Nomenclature and etymology The word ''ketone'' is derived from ''Aketon'', an old German word for ''acetone''. According to the rules of IUPAC nomenclature, ketone names are derived by changing the suffix ''-ane'' of the parent alkane to ''-anone''. Typically, the position of the carbonyl group is denoted by a number, but traditional nonsystematic names are still generally used for the most important ketones, for example acetone and benzophenone. These nonsystematic names are considere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RDH16
Retinol dehydrogenase 16 (all-trans) is a protein that in humans is encoded by the ''RDH16'' gene. The gene is also known as ''RODH-4'' and ''SDR9C8''. Model organisms Model organisms have been used in the study of RDH16 function. A conditional knockout mouse line, called ''Rdh16tm1a(KOMP)Wtsi'' was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists — at the Wellcome Trust Sanger Institute. Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty four tests were carried out on mutant In biology, and especially in genetics, a mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism. It ... mice, but no significant abnormalities were observe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSD17B6
Hydroxysteroid 17-beta dehydrogenase 6 is an enzyme that in humans is encoded by the ''HSD17B6'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba .... The protein encoded by this gene has both oxidoreductase and epimerase activities and is involved in androgen catabolism. The oxidoreductase activity can convert 3 alpha-adiol to dihydrotestosterone, while the epimerase activity can convert androsterone to epi-androsterone. Both reactions use NAD+ as the preferred cofactor. This gene is a member of the retinol dehydrogenase family. Transcript variants utilizing alternative polyadenylation signals exist. References Further reading * * * * * * * * {{gene-12-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androsterone
Androsterone, or 3α-hydroxy-5α-androstan-17-one, is an endogenous steroid hormone, neurosteroid, and putative pheromone. It is a weak androgen with a potency that is approximately 1/7 that of testosterone. Androsterone is a metabolite of testosterone and dihydrotestosterone (DHT). In addition, it can be converted back into DHT via 3α-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase, bypassing conventional intermediates such as androstanedione and testosterone, and as such, can be considered to be a metabolic intermediate in its own right. Androsterone is also known to be an inhibitory androstane neurosteroid, acting as a positive allosteric modulator of the GABAA receptor, and possesses anticonvulsant effects. The unnatural enantiomer of androsterone is more potent as a positive allosteric modulator of GABAA receptors and as an anticonvulsant than the natural form. Androsterone's 3β-isomer is epiandrosterone, and its 5β-epimer is etiocholanolone. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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