کراتین فسفات

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کراتین فسفات نام آیوپاک 2-(Methylguanidino)ethanoic acid[نیازمند منبع] نام‌های دیگر Creatin[نیازمند منبع] Kreatin[نیازمند منبع] 2-(1-Methylcarbamimidamido)acetic acid[نیازمند منبع] (α-Methylguanido)acetic acid[نیازمند منبع] شناساگرها CAS 57-00-1 Y پاب‌کم 586 کم‌اسپایدر 566 Y UNII MU72812GK0 Y شماره EINECS 200-306-6 دراگ‌بانک DB00148 KEGG C00300 Y MeSH Creatine ChEBI CHEBI:16919 N ChEMBL CHEMBL283800 Y شماره RTECS MB7706000 کد اِی‌تی‌سی C01EB06 بیلشتین 907175 Gmelin Reference 240513 3DMet B00084 Jmol-3D images Image 1 Image 2 SMILES C[n](Cc(:[o]):[oH]):c(:[nH]):[nH2] CN(CC(O)=O)C(N)=N InChI InChI=1S/C4H9N3O2/c1-7(4(5)6)2-3(8)9/h2H2,1H3,(H3,5,6)(H,8,9) Y Key: CVSVTCORWBXHQV-UHFFFAOYSA-N Y خصوصیات فرمول مولکولی C4H9N3O2 جرم مولی ۱۳۱٫۱۳ g mol−1 Exact mass 131.069476547 g mol−1 شکل ظاهری White crystals بوی Odourless دمای ذوب ‎255 °C, 528 K, 491 °F محلول در آب 13.3 g L−1 (at 18 °C) log P −1.258 اسیدی (pKa) 3.429 خاصیت بازی (pKb) 10.568 نقطه ایزوالکتریک 8.47 ترموشیمی آنتالپی استاندارد تشکیل ΔfHo298 −538.06–−536.30 kJ mol−1 Std enthalpy of combustion ΔcHo298 −2.3239–−2.3223 MJ mol−1 آنتروپی مولار استاندارد So298 189.5 J K−1 mol−1 ظرفیت گرمایی، C 171.1 J K−1 mol−1 (at 23.2 °C) داروشناسی Elimination half-life 3 hours خطرات GHS pictograms GHS signal word WARNING GHS hazard statements H315, H319, H335 GHS precautionary statements P261, P305+351+338 طبقه‌بندی EU Xi شماره ایمنی R36/37/38 شماره نگهداری S26, S۳۶ ترکیبات مرتبط مرتبط با alkanoic acids Sarcosine دی‌متیل‌گلیسین گلیکوسیامین beta-Methylamino-L-alanine گوانیدینوپروپیونیک اسید ترکیبات مرتبط دی‌متیل‌استامید N-Acetylglycinamide  N (verify) (what is: Y/N?) تمامی داده‌ها مربوط به شرایط استاندارد(در  °C۲۵ و  kPa۱۰۰) است، مگر آنکه خلاف آن ذکر شده باشد. Infobox references کراتین فسفات (Creatine) یک ترکیب نیتروژنه ذخیره کننده فسفات در سلولهای عضلات است و بعد از دهیدارته شدن کراتین و بدون کاتالیزور، کراتین به کراتینین تبدیل می‌شود که بعدا از طریق کلیه‌ها دفع می‌شود. کراتین که منشاء عمده تولید انرژی در عضله‌است. روزانه تقریبا ۲ درصد کراتین بدن به کراتینین تبدیل می‌شود. کراتینین محصول کاتابولیک کراتین فسفات است که در انقباض عضله اسکلتی مصرف می‌شود و سپس با جریان خون به کلیه‌ها می‌رود. متابولیسم کراتین کراتین در متابولیسم عضلات اهمیت فراوانی دارد، زیرا از طریق سنتز فسفوکراتین؛ ملکول پرانرژی ایحاد می‌نماید. این ماده طی دومرحله ساخته می‌شود، ابتدا سنتز گلیکو سیامین می‌باشد که از واکنش بین گلیسین و آرژنین در کلیه ها؛ مخاط روده؛ لوزالمعده و احتمالا درکبد صورت می‌گیرد وحاصل آن بعنوان اثر مهاری تولید از طریق فید بک منفی عمل می‌کند، سپس گلیکوسیامین (گوانیدواستات) به کبد انتقال می‌یابد وپس از متیله شدن تبدیل به کراتین می‌شود، و کراتین حاصل وارد خون شده، درتمام بدن خصوصا بافتهای عضلانی گسترش می‌یابد زیرا بافتهای عضلانی بیشترین مصرف کننده کراتین بوده ومعمولا مقدار کراتین باتوده عضلانی نسبتی متعادل دارد. ودرنهایت کراتینین دراثر دهیدراتاسیون (ازدست دادن آب) کراتین درعضله ایجاد می‌شود. کراتینین آزاد شده دیگردرمتابولیسم بدن مورد استفاده قرار نمی‌گیرد و از کلیه دفع می‌شود. فواید کراتین مونوهیدرات باعث افزایش سنتز پروتئیین و افزایش احتباس آب و املاح و افزایش جذب آمینو اسید‌ها در عضلات اسکلتی شده که این اتفاق باعث افزایش قوای جسمانی بدنساز می‌شود. در ضمن این مکمل به انجام تمرینات سخت کمک کرده و باعث افزایش حجم و توده عضلانی میإشود. عوارض با توجه به عوارض سایر مکملها می‌توان گفت که کراتین مونوهیدرات عوارض محسوسی ندارد. اما در هر حال توجه شود مصرف طولانی مدت با افزایش فشار به کبد وکلیه‌ها می‌تواندایجاد مشکل کند. استفاده مکملها در سنین نوجوانی (قبل از ۱۸ سال) با ایجاد اختلال در وضع طبیعی بدن ، باعث ناهنجاری‌های رشدی و آسیب به اندامهای داخلی مانند کلیه‌ها و کبد و دستگاه گوارشی می‌شود. جستارهای وابسته کراتینین منبع ویکی‌پدیای انگلیسی

For the use of creatine to increase athletic performance, see Creatine supplements. Not to be confused with creatinine. Creatine Systematic name 2-[Carbamimidoyl(methyl)amino]acetic acid Other names N-Carbamimidoyl-N-methylglycine; Methylguanidoacetic acid Identifiers CAS number 57-00-1 Y PubChem 586 ChemSpider 566 Y UNII MU72812GK0 Y EC number 200-306-6 DrugBank DB00148 KEGG C00300 Y MeSH Creatine ChEBI CHEBI:16919 N ChEMBL CHEMBL283800 Y RTECS number MB7706000 ATC code C01EB06 Beilstein Reference 907175 Gmelin Reference 240513 3DMet B00084 Jmol-3D images Image 1 Image 2 SMILES C[n](Cc(:[o]):[oH]):c(:[nH]):[nH2] CN(CC(O)=O)C(N)=N InChI InChI=1S/C4H9N3O2/c1-7(4(5)6)2-3(8)9/h2H2,1H3,(H3,5,6)(H,8,9) Y Key: CVSVTCORWBXHQV-UHFFFAOYSA-N Y Properties Molecular formula C4H9N3O2 Molar mass 131.13 g mol−1 Appearance White crystals Odor Odourless Melting point 255 °C, 528 K, 491 °F Solubility in water 13.3 g L−1 (at 18 °C) log P −1.258 Acidity (pKa) 3.429 Basicity (pKb) 10.568 Isoelectric point 8.47 Thermochemistry Std enthalpy of formation ΔfHo298 −538.06–−536.30 kJ mol−1 Std enthalpy of combustion ΔcHo298 −2.3239–−2.3223 MJ mol−1 Standard molar entropy So298 189.5 J K−1 mol−1 Specific heat capacity, C 171.1 J K−1 mol−1 (at 23.2 °C) Pharmacology Elimination half-life 3 hours Hazards GHS pictograms GHS signal word WARNING GHS hazard statements H315, H319, H335 GHS precautionary statements P261, P305+351+338 EU classification Xi R-phrases R36/37/38 S-phrases S26, S36 Related compounds Related alkanoic acids Sarcosine Dimethylglycine Glycocyamine N-Methyl-D-aspartic acid beta-Methylamino-L-alanine Guanidinopropionic acid Related compounds Dimethylacetamide  N (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references Creatine (/ˈkriːətiːn/ or /ˈkriːətɪn/) is a nitrogenous organic acid that occurs naturally in vertebrates and helps to supply energy to all cells in the body, primarily muscle. This is achieved by increasing the formation of adenosine triphosphate (ATP). Creatine was identified in 1832 when Michel Eugène Chevreul discovered it as a component of skeletal muscle, which he later named after the Greek word for meat, κρέας (kreas). In solution, creatine is in equilibrium with creatinine. Biosynthesis Creatine is naturally produced in the human body from amino acids primarily in the kidney and liver. It is transported in the blood for use by muscles. Approximately 95% of the human body's total creatine is located in skeletal muscle. Creatine is not an essential nutrient, as it is manufactured in the human body from L-arginine, glycine, and L-methionine. In humans and animals, approximately half of stored creatine originates from food (about 1 g/day, mainly from meat). A study, involving 18 vegetarians and 24 non-vegetarians, on the effect of creatine in vegetarians showed that total creatine was significantly lower than in non-vegetarians. Since vegetables are not the primary source of creatine, vegetarians can be expected to show lower levels of directly derived muscle creatine. However, the subjects happened to show the same levels after using supplements. Given the fact that creatine can be synthesized from the above mentioned amino acids, protein sources rich in these amino acids can be expected to provide adequate capability of native biosynthesis in the human body. The enzyme GATM (L-arginine:glycine amidinotransferase (AGAT), EC 2.1.4.1) is a mitochondrial enzyme responsible for catalyzing the first rate-limiting step of creatine biosynthesis, and is primarily expressed in the kidneys and pancreas. The second enzyme in the pathway (GAMT, Guanidinoacetate N-methyltransferase, EC:2.1.1.2) is primarily expressed in the liver and pancreas. Genetic deficiencies in the creatine biosynthetic pathway lead to various severe neurological defects. The pathway for the synthesis of creatine Arg - Arginine; GATM - Glycine amidinotransferase; GAMT - Guanidinoacetate N-methyltransferase; Gly - Glycine; Met - Methionine; SAH - S-adenosyl homocysteine; SAM - S-adenosyl methionine. The color scheme is as follows:enzymes, coenzymes and the Met part, substrate names, the Gly part, the Arg part The phosphocreatine system Creatine, synthesized in the liver and kidney, is transported through the blood and taken up by tissues with high energy demands, such as the brain and skeletal muscle, through an active transport system. The concentration of ATP in skeletal muscle is usually 2-5 mM, which would result in a muscle contraction of only a few seconds. Fortunately, during times of increased energy demands, the phosphagen (or ATP/PCr) system rapidly resynthesizes ATP from ADP with the use of phosphocreatine (PCr) through a reversible reaction with the enzyme creatine kinase (CK). In skeletal muscle, PCr concentrations may reach 20-35 mM or more. Additionally, in most muscles, the ATP regeneration capacity of CK is very high and is therefore not a limiting factor. Although the cellular concentrations of ATP are small, changes are difficult to detect because ATP is continuously and efficiently replenished from the large pools of PCr and CK. Creatine has the ability to increase muscle stores of PCr, potentially increasing the muscle’s ability to resynthesize ATP from ADP to meet increased energy demands. For a review of the creatine kinase system and the pleiotropic actions of creatine and creatine supplementation see. Health effects Use as a supplement Main article: Creatine supplements Creatine supplements are used by athletes, bodybuilders, wrestlers, sprinters, and others who wish to gain muscle mass, typically consuming 2 to 3 times the amount that could be obtained from a very-high-protein diet. The Mayo Clinic states that creatine has been associated with asthmatic symptoms and warns against consumption by persons with known allergies to creatine. There was once some concern that creatine supplementation could affect hydration status and heat tolerance and lead to muscle cramping and diarrhea, but recent studies have shown these concerns to be unfounded. There are reports of kidney damage with creatine use, such as interstitial nephritis; patients with kidney disease should avoid use of this supplement. In similar manner, liver function may be altered, and caution is advised in those with underlying liver disease, although studies have shown little or no adverse impact on kidney or liver function from oral creatine supplementation. In 2004 the European Food Safety Authority (EFSA) published a record which stated that oral long-term intake of 3g pure creatine per day is risk-free. The reports of damage to the kidneys by creatine supplementation have been scientifically refuted. Long-term administration of large quantities of creatine is reported to increase the production of formaldehyde, which has the potential to cause serious unwanted side-effects. However, this risk is largely theoretical because urinary excretion of formaldehyde, even under heavy creatine supplementation, does not exceed normal limits. Extensive research has shown that oral creatine supplementation at a rate of 5 to 20 grams per day appears to be very safe and largely devoid of adverse side-effects, while at the same time effectively improving the physiological response to resistance exercise, increasing the maximal force production of muscles in both men and women. A meta analysis performed in 2008 found that creatine treatment resulted in no abnormal renal, hepatic, cardiac or muscle function. Pharmacokinetics Endogenous serum or plasma creatine concentrations in healthy adults are normally in a range of 2–12 mg/L. A single 5 g (5000 mg) oral dose in healthy adults results in a peak plasma creatine level of approximately 120 mg/L at 1–2 hours post-ingestion. Creatine has a fairly short elimination half-life, averaging just less than 3 hours, so to maintain an elevated plasma level it would be necessary to take small oral doses every 3–6 hours throughout the day. After the "loading dose" period (1–2 weeks, 12-24 g a day), it is no longer necessary to maintain a consistently high serum level of creatine. As with most supplements, each person has their own genetic "preset" amount of creatine they can hold. The rest is eliminated out of the body as waste. Creatine is consumed by the body fairly quickly, and if one wishes to maintain the high concentration of creatine, Post-loading dose, 2-5 g daily is the standard amount to intake. Pregnancy and breastfeeding Creatine cannot be recommended during pregnancy or breastfeeding due to a lack of scientific information.[citation needed] Pasteurized cow's milk contains higher levels of creatine than human milk. Treatment of diseases Creatine has been demonstrated to cause modest increases in strength in people with a variety of neuromuscular disorders. Creatine supplementation has been, and continues to be, investigated as a possible therapeutic approach for the treatment of muscular, neuromuscular, neurological and neurodegenerative diseases (arthritis, congestive heart failure, Parkinson's disease, disuse atrophy, gyrate atrophy, McArdle's disease, Huntington's disease, miscellaneous neuromuscular diseases, mitochondrial diseases, muscular dystrophy, and neuroprotection), and depression.[citation needed] A study demonstrated that creatine is twice as effective as the prescription drug riluzole in extending the lives of mice with the degenerative neural disease amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease). The neuroprotective effects of creatine in the mouse model of ALS may be due either to an increased availability of energy to injured nerve cells or to a blocking of the chemical pathway that leads to cell death. A similarly promising result has been obtained in prolonging the life of transgenic mice affected by Huntington's disease. Creatine treatment lessened brain atrophy and the formation of intranuclear inclusions, attenuated reductions in striatal N-acetylaspartate, and delayed the development of hyperglycemia. Treatment of muscle disorders A meta analysis found that creatine treatment increased muscle strength in muscular dystrophies, and potentially improved functional performance. It has also been implicated in decreasing mutagenesis in DNA Improved cognitive ability A placebo-controlled double-blind experiment found that a group of subjects composed of vegetarians and vegans who took 5 grams of creatine per day for six weeks showed a significant improvement on two separate tests of fluid intelligence, Raven's Progressive Matrices, and the backward digit span test from the WAIS. The treatment group was able to repeat longer sequences of numbers from memory and had higher overall IQ scores than the control group. The researchers concluded that "supplementation with creatine significantly increased intelligence compared with placebo." A subsequent study found that creatine supplements improved cognitive ability in the elderly. A study on young adults (0.03 g/kg/day for six weeks, e.g., 2 g/day for a 70-kilogram (150 lb) individual) failed to find any improvements. See also Adenosine triphosphate Beta-Alanine Creatine phosphate References External links Creatine bound to proteins in the PDB Creatine Supplementation, Beth Lulinski, Quackwatch Creatine 'boosts brain power', BBC News, 12 August 2003 Creatine Supplementation International Society of Sports Nutrition position stand: Creatine