|
Vitamin D Analogue
The natural, active form of vitamin D is calcitriol (1,25-dihydroxycholecalciferol). This molecule and other naturally occurring forms of vitamin D, including its precursors and metabolites, have been modified to synthesize pharmaceuticals with potentially greater, or selective, therapeutic actions. Types These include: * Alfacalcidol * Calcipotriol (calcipotriene) * Doxercalciferol * Falecalcitriol * Paricalcitol * Tacalcitol Mechanisms These modified vitamin D analogues have a side chain or other modifications. They aim to reduce the classical renal and intestinal effects of calcitriol on calcium and phosphate homeostasis, from its effects on other biologic processes. They target cell proliferation and differentiation, especially in skin, or other effects in the parathyroid gland (secondary hyperparathyroidism Hyperparathyroidism is an increase in parathyroid hormone (PTH) levels in the blood. This occurs from a disorder either within the parathyroid glands ( primary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin D
Vitamin D is a group of structurally related, fat-soluble compounds responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, along with numerous other biological functions. In humans, the most important compounds within this group are vitamin D3 ( cholecalciferol) and vitamin D2 ( ergocalciferol). Unlike the other twelve vitamins, vitamin D is only conditionally essential, as with adequate skin exposure to the ultraviolet B (UVB) radiation component of sunlight there is synthesis of cholecalciferol in the lower layers of the skin's epidermis. For most people, skin synthesis contributes more than diet sources. Vitamin D can also be obtained through diet, food fortification and dietary supplements. In the U.S., cow's milk and plant-based milk substitutes are fortified with vitamin D3, as are many breakfast cereals. Government dietary recommendations typically assume that all of a person's vitamin D is taken by mouth, given the potential for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcitriol
Calcitriol is a hormone and the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. Calcitriol increases blood Calcium in biology, calcium mainly by increasing the uptake of calcium from the intestines. It can be given as a medication for the treatment of hypocalcemia, low blood calcium and hyperparathyroidism due to kidney disease, low blood calcium due to hypoparathyroidism, osteoporosis, osteomalacia, and familial hypophosphatemia, and can be taken by mouth or by intravenous, injection into a vein. Excessive amounts or intake can result in weakness, headache, nausea, constipation, urinary tract infections, and abdominal pain. Serious side effects may include high blood calcium and anaphylaxis. Calcitriol was identified as the active form of vitamin D in 1971 and the drug was approved for medic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pharmaceuticals
Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the medical field and relies on the science of pharmacology for continual advancement and on pharmacy for appropriate management. Drugs are classified in many ways. One of the key divisions is by level of control, which distinguishes prescription drugs (those that a pharmacist dispenses only on the medical prescription) from over-the-counter drugs (those that consumers can order for themselves). Medicines may be classified by mode of action, route of administration, biological system affected, or therapeutic effects. The World Health Organization keeps a list of essential medicines. Drug discovery and drug development are complex and expensive endeavors undertaken by pharmaceutical companies, academic scientists, and governments. As a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfacalcidol
Alfacalcidol (or 1-hydroxycholecalciferol) is an analogue of vitamin D used for supplementation in humans and as a poultry feed additive. Alfacalcidol has a weaker impact on calcium metabolism and parathyroid hormone levels than calcitriol; but significant effects on the immune system, including regulatory T cells. It is considered to be a more useful form of vitamin D supplementation, mostly due to its much longer half-life and lower kidney load. It is the most commonly prescribed vitamin D metabolite for patients with end stage renal disease, given that impaired renal function alters the ability to carry out the second hydroxylation step required for the formation of the physiologically active form of vitamin D, 1,25-dihydroxyvitamin D3. Alfacalcidol is an active vitamin D3 metabolite, and therefore does not require the second hydroxylation step in the kidney. It was patented in 1971 and approved for medical use in 1978. Trade names Pharmaceutical trade names include AlphaD ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcipotriol
Calcipotriol, also known as calcipotriene and sold under the brand name Dovonex among others, is a synthetic derivative of calcitriol, a form of vitamin D. It is used in the treatment of psoriasis. It was patented in 1985 and approved for medical use in 1991. It is on the World Health Organization's List of Essential Medicines. Calcipotriol is also available with the synthetic corticosteroid betamethasone dipropionate as the fixed-dose combination medication calcipotriol/betamethasone dipropionate for the treatment of plaque psoriasis. Medical uses Chronic plaque psoriasis is the chief medical use of calcipotriol. It has also been used successfully in the treatment of alopecia areata. Contraindications Hypersensitivity, use on face, hypercalcaemia, or evidence of vitamin D toxicity are the only contraindications for calcipotriol use. Cautions include exposure to excessive natural or artificial light, due to the potential for calcipotriol to cause photosensitivity. Adve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doxercalciferol
Doxercalciferol (or 1-hydroxyergocalciferol, trade name Hectorol) is drug for secondary hyperparathyroidism and metabolic bone disease. It is a synthetic analog of ergocalciferol (vitamin D2). It suppresses parathyroid synthesis and secretion. Doxercalciferol is the vitamin D2 analogue of alfacalcidol. It undergoes 25-hydroxylation in the liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ... to become the active ercalcitriol, without the involvement of kidneys. References Secosteroids Diols Vitamin D Sanofi {{systemic-hormonal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falecalcitriol
Falecalcitriol (INN) is an analog of calcitriol Calcitriol is a hormone and the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the exp .... It has a higher potency both in vivo and in vitro systems, and longer duration of action in vivo. References Secosteroids Trifluoromethyl compounds Vitamin D {{gastrointestinal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paricalcitol
Paricalcitol (chemically it is 19-nor-1,25-(OH)2-vitamin D2. Marketed by Abbott Laboratories under the trade name Zemplar) is a drug used for the prevention and treatment of secondary hyperparathyroidism (excessive secretion of parathyroid hormone) associated with chronic kidney failure. It is an analog of 1,25-dihydroxyergocalciferol, the active form of vitamin D2 (ergocalciferol). It was patented in 1989 and approved for medical use in 1998. Medical uses Its primary use in medicine is in the treatment of secondary hyperparathyroidism associated with chronic kidney disease. However a 2016 systematic review did not find evidence sufficient to demonstrate an advantage of paricalcitol over non-selective vitamin D derivatives for this indication. Adverse effects Adverse effects by frequency: Very common (>10% frequency): * Nausea Common (1-10% frequency): * Diarrhoea† * Oedema * Allergic reaction * Arthritis * Dizziness† * Stomach discomfort‡ * Gastroesophageal reflux ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tacalcitol
Tacalcitol (1,24-dihydroxyvitamin D3) is a synthetic vitamin D3 analog. Tacalcitol is marketed under several names, including Curatoderm and Bonalfa. It is on the World Health Organization's List of Essential Medicines. Mechanism Tacalcitol reduces excessive cell turnover in the epidermis by interacting with vitamin D receptors on keratinocytes. Uses It is usually prescribed by a general practitioner or dermatologist for the treatment of psoriasis, chronic chapped lips and other severe dry skin conditions because of its ability to reduce excessive skin cell turnover. It is available as an ointment or lotion. It has also been used for vitiligo Vitiligo (, ) is a chronic autoimmune disorder that causes patches of skin to lose pigment or color. The cause of vitiligo is unknown, but it may be related to immune system changes, genetic factors, stress, or sun exposure, and susceptibili ... and Hailey-Hailey disease. References Secosteroids Vitamin D {{Vita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Side Chain
In organic chemistry and biochemistry, a side chain is a substituent, chemical group that is attached to a core part of the molecule called the "main chain" or backbone chain, backbone. The side chain is a hydrocarbon branching element of a molecule that is attached to a larger hydrocarbon backbone. It is one factor in determining a molecule's properties and reactivity. A side chain is also known as a pendant chain, but a pendant group (side group) has a different definition. Conventions The placeholder R is often used as a generic placeholder for alkyl (saturated hydrocarbon) group side chains in structural formulae. To indicate other non-carbon groups in structure diagrams, X, Y, or Z are often used. History The ''R'' symbol was introduced by 19th-century French chemist Charles Frédéric Gerhardt, who advocated its adoption on the grounds that it would be widely recognizable and intelligible given its correspondence in multiple European languages to the initial letter of "r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Homeostasis
Calcium metabolism is the movement and regulation of calcium ions (Ca2+) ''in'' (via the gut) and ''out'' (via the gut and kidneys) of the body, and ''between'' body compartments: the blood plasma, the extracellular and intracellular fluids, and bone. Bone acts as a calcium storage center for deposits and withdrawals as needed by the blood via continual bone remodeling. An important aspect of calcium metabolism is plasma calcium homeostasis, the regulation of calcium ions in the blood plasma within narrow limits. The level of the calcium in plasma is regulated by the hormones parathyroid hormone (PTH) and calcitonin. PTH is released by the chief cells of the parathyroid glands when the plasma calcium level falls below the normal range in order to raise it; calcitonin is released by the parafollicular cells of the thyroid gland when the plasma level of calcium is above the normal range in order to lower it. Body compartment content Calcium is the most abundant miner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphate
Phosphates are the naturally occurring form of the element phosphorus. In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid, phosphoric acid . The phosphate or orthophosphate ion is derived from phosphoric acid by the removal of three protons . Removal of one proton gives the dihydrogen phosphate ion while removal of two protons gives the hydrogen phosphate ion . These names are also used for salts of those anions, such as ammonium dihydrogen phosphate and trisodium phosphate. File:3-phosphoric-acid-3D-balls.png, Phosphoricacid File:2-dihydrogenphosphate-3D-balls.png, Dihydrogenphosphate File:1-hydrogenphosphate-3D-balls.png, Hydrogenphosphate File:0-phosphate-3D-balls.png, Phosphate or orthophosphate In organic chemistry, phosphate or orthophosphate is an organophosphate, an ester of orthophosphoric acid of the form where one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
