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MK-386
MK-386, also known as 4,7β-dimethyl-4-aza-5α-cholestan-3-one, is a synthetic, steroidal 5α-reductase inhibitor which was first reported in 1994 and was never marketed. It is a 4-azasteroid and a potent and selective inhibitor of 5α-reductase type I and shows high selectivity for inhibition of human 5α-reductase type I over 5α-reductase type II, with IC50 values of 0.9 nM and 154 nM, respectively. The drug was under investigation for potential treatment of androgen-dependent conditions such as acne and pattern hair loss (androgenic alopecia or baldness), but was discontinued in early clinical trials due to observations of hepatotoxicity such as elevated liver enzymes. MK-386 has been found to decrease circulating concentrations of dihydrotestosterone (DHT) in men by 20 to 30%, which is in accordance with the fact that 5α-reductase type II is responsible for 70 to 80% of DHT production while 5α-reductase type I is responsible for 20 to 30%. In contrast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 including the prostate gland, seminal vesicles, epididymides, skin, hair follicles, liver, and brain. This enzyme mediates reduction of the C4-5 double bond of testosterone. Relative to testosterone, DHT is considerably more potent as an agonist of the androgen receptor (AR). In addition to its role as a natural hormone, DHT has been used as a medication, for instance in the treatment of low testosterone levels in men; for information on DHT as a medication, see the androstanolone article. Biological function DHT is biologically important for sexual differentiation of the male genitalia during embryogenesis, maturation of the penis and scrotum at puberty, growth of facial, body, and pubic hair, and development and maintenance of the pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-Reductase Inhibitors
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of 5α-reductase encoded by the genes SRD5A1, SRD5A2, and SRD5A3. 5α-Reductases catalyze the following generalized chemical reaction: :a 3-oxo-5α-steroid + acceptor a 3-oxo-Δ4-steroid + reduced acceptor Where a 3-oxo-5α-steroid and acceptor are substrates, and a corresponding 3-oxo-Δ4-steroid and the reduced acceptor are products. An instance of this generalized reaction that 5α-reductase type 2 catalyzes is: :dihydrotestosterone + NADP+ \rightleftharpoons testosterone + NADPH + H+ where dihydrotestosterone is the 3-oxo-5α-steroid, NADP+ is the acceptor and testosterone is the 3-oxo-Δ4-steroid and NADPH the reduced acceptor. Production and activity The enzyme is produced in many tissues in both males and females, in the rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-reductase Inhibitor
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of 5α-reductase encoded by the genes SRD5A1, SRD5A2, and SRD5A3. 5α-Reductases catalyze the following generalized chemical reaction: :a 3-oxo-5α-steroid + acceptor a 3-oxo-Δ4-steroid + reduced acceptor Where a 3-oxo-5α-steroid and acceptor are substrates, and a corresponding 3-oxo-Δ4-steroid and the reduced acceptor are products. An instance of this generalized reaction that 5α-reductase type 2 catalyzes is: :dihydrotestosterone + NADP+ \rightleftharpoons testosterone + NADPH + H+ where dihydrotestosterone is the 3-oxo-5α-steroid, NADP+ is the acceptor and testosterone is the 3-oxo-Δ4-steroid and NADPH the reduced acceptor. Production and activity The enzyme is produced in many tissues in both males and females, in the rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-reductase
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of 5α-reductase encoded by the genes SRD5A1, SRD5A2, and SRD5A3. 5α-Reductases catalyze the following generalized chemical reaction: :a 3-oxo-5α-steroid + acceptor a 3-oxo-Δ4-steroid + reduced acceptor Where a 3-oxo-5α-steroid and acceptor are substrates, and a corresponding 3-oxo-Δ4-steroid and the reduced acceptor are products. An instance of this generalized reaction that 5α-reductase type 2 catalyzes is: :dihydrotestosterone + NADP+ \rightleftharpoons testosterone + NADPH + H+ where dihydrotestosterone is the 3-oxo-5α-steroid, NADP+ is the acceptor and testosterone is the 3-oxo-Δ4-steroid and NADPH the reduced acceptor. Production and activity The enzyme is produced in many tissues in both males and females, in the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5α-Reductase Inhibitor
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of 5α-reductase encoded by the genes SRD5A1, SRD5A2, and SRD5A3. 5α-Reductases catalyze the following generalized chemical reaction: :a 3-oxo-5α-steroid + acceptor a 3-oxo-Δ4-steroid + reduced acceptor Where a 3-oxo-5α-steroid and acceptor are substrates, and a corresponding 3-oxo-Δ4-steroid and the reduced acceptor are products. An instance of this generalized reaction that 5α-reductase type 2 catalyzes is: :dihydrotestosterone + NADP+ \rightleftharpoons testosterone + NADPH + H+ where dihydrotestosterone is the 3-oxo-5α-steroid, NADP+ is the acceptor and testosterone is the 3-oxo-Δ4-steroid and NADPH the reduced acceptor. Production and activity The enzyme is produced in many tissues in both males and females, in the rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Administration
Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are intended to have a systemic effect, reaching different parts of the body via the bloodstream, for example. Oral administration can be easier and less painful than other routes, such as injection. However, the onset of action is relatively low, and the effectiveness is reduced if it is not absorbed properly in the digestive system, or if it is broken down by digestive enzymes before it can reach the bloodstream. Some medications may cause gastrointestinal side effects, such as nausea or vomiting, when taken orally. Oral administration can also only be applied to conscious patients, and patients willing and able to swallow. Terminology ''Per os'' (; ''P.O.'') is an adverbial phrase meaning literally from Latin "through the mouth" or "by mouth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatotoxicity
Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn from the market after approval. The liver plays a central role in transforming and clearing chemicals and is susceptible to the toxicity from these agents. Certain medicinal agents, when taken in overdoses (e.g. paracetamol) and sometimes even when introduced within therapeutic ranges (e.g. halothane), may injure the organ. Other chemical agents, such as those used in laboratories and industries, natural chemicals (e.g., microcystins), and herbal remedies (two prominent examples being kava, mechanism unknown, and comfrey, through its pyrrolizidine alkaloid content) can also induce hepatotoxicity. Chemicals that cause liver injury are called hepatotoxins. More than 900 drugs have been implicated in causing liver injury (see LiverTox, exter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minocycline
Minocycline, sold under the brand name Minocin among others, is a tetracycline antibiotic medication used to treat a number of bacterial infections such as pneumonia. It is generally less preferred than the tetracycline doxycycline. It is also used for the treatment of acne and rheumatoid arthritis. It is taken by mouth or applied to the skin. Common side effects include nausea, diarrhea, dizziness, allergic reactions, and kidney problems. Serious side effects may include anaphylaxis, a lupus-like syndrome, and easy sunburning. Use in the later part of pregnancy may harm the baby and safety during breastfeeding is unclear. It works by decreasing a bacterium's ability to make protein thus stopping its growth. Minocycline was patented in 1961 and came into commercial use in 1971. It is available as a generic medication. In 2020, it was the 236th most commonly prescribed medication in the United States, with more than 1million prescriptions. Medical uses Acne Minocycline and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibiotic
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the common cold or influenza; drugs which inhibit viruses are termed antiviral drugs or antivirals rather than antibiotics. Sometimes, the term ''antibiotic''—literally "opposing life", from the Greek roots ἀντι ''anti'', "against" and βίος ''bios'', "life"—is broadly used to refer to any substance used against microbes, but in the usual medical usage, antibiotics (such as penicillin) are those produced naturally (by one microorganism fighting another), whereas non-antibiotic antibacterials (such as sulfonamides and antiseptics) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placebo
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures. In general, placebos can affect how patients perceive their condition and encourage the body's chemical processes for relieving pain and a few other symptoms, but have no impact on the disease itself. Improvements that patients experience after being treated with a placebo can also be due to unrelated factors, such as regression to the mean (a statistical effect where an unusually high or low measurement is likely to be followed by a less extreme one). The use of placebos in clinical medicine raises ethical concerns, especially if they are disguised as an active treatment, as this introduces dishonesty into the doctor–patient relationship and bypasses informed consent. While it was once assumed that this deception was necessary for placebos to have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semen
Semen, also known as seminal fluid, is an organic bodily fluid created to contain spermatozoa. It is secreted by the gonads (sexual glands) and other sexual organs of male or hermaphroditic animals and can fertilize the female ovum. Semen is produced and originates from the seminal vesicle, which is located in the pelvis. The process that results in the discharge of semen from the urethral orifice is called ejaculation. In humans, seminal fluid contains several components besides spermatozoa: proteolytic and other enzymes as well as fructose are elements of seminal fluid which promote the survival of spermatozoa, and provide a medium through which they can move or "swim". The fluid is designed to be discharged deep into the vagina, so the spermatozoa can pass into the uterus and form a zygote with an egg. Semen is also a form of genetic material. In animals, semen has been collected for cryoconservation. Cryoconservation of animal genetic resources is a practice that call ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sebum
A sebaceous gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in the greatest number on the face and scalp, but also on all parts of the skin except the palms of the hands and soles of the feet. In the eyelids, meibomian glands, also called tarsal glands, are a type of sebaceous gland that secrete a special type of sebum into tears. Surrounding the female nipple, areolar glands are specialized sebaceous glands for lubricating the nipple. Fordyce spots are benign, visible, sebaceous glands found usually on the lips, gums and inner cheeks, and genitals. Structure Location Sebaceous glands are found throughout all areas of the skin, except the palms of the hands and soles of the feet. There are two types of sebaceous glands, those connected to hair follicles and those that exist independently. Sebaceous glands ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
