| Revision as of 19:35, 5 November 2011 editGeorgeButel (talk | contribs)77 editsm Changed ligant to ligand. Although the term "ligant" has been used in a few pubs, the vast majority use the term "ligand."← Previous edit | Revision as of 04:02, 27 January 2012 edit undoDrphilharmonic (talk | contribs)6,066 editsmNo edit summaryNext edit → | ||
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| '''β-Alanine''' (or '''''beta''-alanine''') is a naturally occurring ], which |
'''β-Alanine''' (or '''''beta''-alanine''') is a naturally occurring ], which is an ] in which the ] group is at the β-position from the carboxylate group (i.e., two atoms away, see Figure 1). The ] name for β-alanine would be '''3-aminopropanoic acid'''. Unlike its normal counterpart, ], β-alanine has no chiral center. | ||
| β-Alanine is not used in the ] of any major ]s or ]s. It is formed ] by the degradation of ] and ]. It is a component of the naturally occurring ] carnosine and ] and also of ] (vitamin B<sub>5</sub>) which itself is a component of ]. Under normal conditions, β-alanine is ] into ]. | β-Alanine is not used in the ] of any major ]s or ]s. It is formed ] by the degradation of ] and ]. It is a component of the naturally occurring ] carnosine and ] and also of ] (vitamin B<sub>5</sub>), which itself is a component of ]. Under normal conditions, β-alanine is ] into ]. | ||
| β-Alanine is the rate-limiting precursor of ], which is to say carnosine levels are limited by the amount of available β-alanine. Supplementation with β-alanine has been shown to increase the concentration of carnosine in muscles, decrease fatigue in athletes and increase total muscular work done.<ref>{{cite journal|author=Derave W, Ozdemir MS, Harris R, Pottier A, Reyngoudt H, Koppo K, Wise JA, Achten E. |title=Beta-alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters |journal=J Appl Physiol |date=August 9, 2007 |pmid = 17690198 |doi=10.1152/japplphysiol.00397.2007 |volume=103|issue=5 |pages=1736 }}</ref><ref name="Hill2007">{{cite journal|author=Hill CA, Harris RC, Kim HJ, Harris BD, Sale C, Boobis LH, Kim CK, Wise JA. |title=Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity |journal= Amino Acids |year=2007 |issue=2 |volume=32 |pages=225–33 |pmid =16868650 |doi=10.1007/s00726-006-0364-4 }}</ref> | β-Alanine is the rate-limiting precursor of ], which is to say carnosine levels are limited by the amount of available β-alanine. Supplementation with β-alanine has been shown to increase the concentration of carnosine in muscles, decrease fatigue in athletes and increase total muscular work done.<ref>{{cite journal|author=Derave W, Ozdemir MS, Harris R, Pottier A, Reyngoudt H, Koppo K, Wise JA, Achten E. |title=Beta-alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters |journal=J Appl Physiol |date=August 9, 2007 |pmid = 17690198 |doi=10.1152/japplphysiol.00397.2007 |volume=103|issue=5 |pages=1736 }}</ref><ref name="Hill2007">{{cite journal|author=Hill CA, Harris RC, Kim HJ, Harris BD, Sale C, Boobis LH, Kim CK, Wise JA. |title=Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity |journal= Amino Acids |year=2007 |issue=2 |volume=32 |pages=225–33 |pmid =16868650 |doi=10.1007/s00726-006-0364-4 }}</ref> | ||
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| ] | ] | ||
| Typically studies have used supplementing strategies of multiple doses of 400 mg or 800 mg, administered at regular intervals for up to eight hours, over periods ranging from 4 to 10 weeks.<ref name="Hill2007"/><ref name="Harris2006">{{Cite journal | doi = 10.1007/s00726-006-0299-9 | last1 = Harris | first1 = RC | last2 = Tallon | first2 = MJ | last3 = Dunnett | first3 = M | last4 = Boobis | first4 = L | last5 = Coakley | first5 = J | last6 = Kim | first6 = HJ | last7 = Fallowfield | first7 = JL | last8 = Hill | first8 = CA | last9 = Sale | first9 = C ''et al.'' | year = 2006 | title = The absorption of orally supplied β-alanine and its effect on muscle carnosine synthesis in human vastus lateralis | url = | journal = Amino Acids | volume = 30 | issue = 3| pages = 279–289 | pmid = 16554972 }}</ref> After a 10 |
Typically, studies have used supplementing strategies of multiple doses of 400 mg or 800 mg, administered at regular intervals for up to eight hours, over periods ranging from 4 to 10 weeks.<ref name="Hill2007"/><ref name="Harris2006">{{Cite journal | doi = 10.1007/s00726-006-0299-9 | last1 = Harris | first1 = RC | last2 = Tallon | first2 = MJ | last3 = Dunnett | first3 = M | last4 = Boobis | first4 = L | last5 = Coakley | first5 = J | last6 = Kim | first6 = HJ | last7 = Fallowfield | first7 = JL | last8 = Hill | first8 = CA | last9 = Sale | first9 = C ''et al.'' | year = 2006 | title = The absorption of orally supplied β-alanine and its effect on muscle carnosine synthesis in human vastus lateralis | url = | journal = Amino Acids | volume = 30 | issue = 3| pages = 279–289 | pmid = 16554972 }}</ref> After a 10-week supplementing strategy, the reported increase in intramuscular carnosine content was an average of 80.1% (range 18 to 205%).<ref name="Hill2007"/> | ||
| <small>L</small>-], with a pKa of 6.1 is a relatively weak buffer over the physiological intramuscular pH range. However, when bound to other amino acids this increases nearer to 6.8-7.0. In particular, when bound to β-alanine the pKa value is 6.83,<ref>{{Cite journal | last1 = Bate-Smith | first1 = EC | year = 1938 | title = The buffering of muscle in rigor: protein, phosphate and carnosine | url = | journal = Journal of Physiology | volume = 92 | issue = 3| pages = 336–343 | pmid = 16994977 | pmc = 1395289 }}</ref> making this a very efficient intramuscular buffer. Furthermore, because of the position of the beta amino group, β-alanine dipeptides are not incorporated proteins and thus can be stored at relatively high concentrations (millimolar). Occurring at 17-25 mmol/kg (dry muscle),<ref>{{Cite journal | doi = 10.1007/BF00376439 | last1 = Mannion | first1 = AF | last2 = Jakeman | first2 = PM | last3 = Dunnett | first3 = M | last4 = Harris | first4 = RC | last5 = Willan | first5 = PLT | year = 1992 | title = Carnosine and anserine concentrations in the quadriceps femoris muscle of healthy humans | url = | journal = Eur. J. Appl. Physiol | volume = 64 | issue = | pages = 47–50 }}</ref> carnosine (β-alanyl-<small>L</small>-histidine) is an important intramuscular buffer, constituting 10-20% of the total buffering capacity in type I and II muscle fibres. | <small>L</small>-], with a pKa of 6.1 is a relatively weak buffer over the physiological intramuscular pH range. However, when bound to other amino acids, this increases nearer to 6.8-7.0. In particular, when bound to β-alanine, the pKa value is 6.83,<ref>{{Cite journal | last1 = Bate-Smith | first1 = EC | year = 1938 | title = The buffering of muscle in rigor: protein, phosphate and carnosine | url = | journal = Journal of Physiology | volume = 92 | issue = 3| pages = 336–343 | pmid = 16994977 | pmc = 1395289 }}</ref> making this a very efficient intramuscular buffer. Furthermore, because of the position of the beta amino group, β-alanine dipeptides are not incorporated proteins and thus can be stored at relatively high concentrations (millimolar). Occurring at 17-25 mmol/kg (dry muscle),<ref>{{Cite journal | doi = 10.1007/BF00376439 | last1 = Mannion | first1 = AF | last2 = Jakeman | first2 = PM | last3 = Dunnett | first3 = M | last4 = Harris | first4 = RC | last5 = Willan | first5 = PLT | year = 1992 | title = Carnosine and anserine concentrations in the quadriceps femoris muscle of healthy humans | url = | journal = Eur. J. Appl. Physiol | volume = 64 | issue = | pages = 47–50 }}</ref> carnosine (β-alanyl-<small>L</small>-histidine) is an important intramuscular buffer, constituting 10-20% of the total buffering capacity in type I and II muscle fibres. | ||
| β-Alanine, provided in solution or as powder in gelatine capsules, however, causes ] when ingested in amounts above 10 mg per kg body weight (bwt).<ref name="Harris2006"/> This is variable between individuals. Symptoms may be experienced by some individuals as mild even at 10 mg per kg bwt, in a majority as significant at 20 mg per kg bwt, and severe at 40 mg per kg bwt.<ref name="Harris2006"/> However, an equivalent amount (equimolar) to 40 mg per kg bwt, ingested in the form of histidine containing dipeptides in chicken broth extract, did not cause paraesthesia.<ref name="Harris2006"/> | β-Alanine, provided in solution or as powder in gelatine capsules, however, causes ] when ingested in amounts above 10 mg per kg body weight (bwt).<ref name="Harris2006"/> This is variable between individuals. Symptoms may be experienced by some individuals as mild even at 10 mg per kg bwt, in a majority as significant at 20 mg per kg bwt, and severe at 40 mg per kg bwt.<ref name="Harris2006"/> However, an equivalent amount (equimolar) to 40 mg per kg bwt, ingested in the form of histidine containing dipeptides in chicken broth extract, did not cause paraesthesia.<ref name="Harris2006"/> | ||
| It is probable that the ], a form of neuropathic pain, results from high peak blood-plasma concentrations of β-alanine since greater quantities, ingested in the form of the β-alanine |
It is probable that the ], a form of neuropathic pain, results from high peak blood-plasma concentrations of β-alanine, since greater quantities, ingested in the form of the β-alanine/histidine (or methylhistidine)-containing dipeptides (i.e., carnosine and anserine) in meat, do not cause the same symptoms. In this case the β-alanine absorption profile is flattened but sustained for a longer period of time,<ref name="Harris2006"/> whereas the β-alanine samples in the studies were administered as gelatine capsules containing powder. This resulted in the rapid rise of plasma concentrations, peaking within 30 to 45 minutes, and being eliminated after 90 to 120 minutes. The paraesthesia caused is no indication of efficacy, since the published studies undertaken so far have utilised doses of 400 mg or 800 mg at a time to avoid the paraesthesia. Furthermore, excretion of β-alanine in urine accounted for 0.60%(+/-0.09), 1.50%(+/-0.40), or 3.64%(+/-0.47) of the administered doses of 10, 20, or 40 mg per kg body weight,<ref name="Harris2006"/> indicating greater losses occurring with increasing dosage. | ||
| Even though much weaker than ] (and thus with a debated role as a physiological transmitter), β-alanine is an agonist next in activity to the cognate ligand glycine itself, for ]-sensitive inhibitory ]s (GlyRs) (the agonist order: glycine >> β-alanine > taurine >> alanine, <small>L</small>-serine > proline).<ref>''Encyclopedia of Life Sciences'' Amino Acid Neurotransmitters. Jeremy M Henley, 2001 John Wiley & Sons, Ltd. {{DOI|10.1038/npg.els.0000010}}, Article Online Posting Date: April 19, 2001</ref> | Even though much weaker than ] (and, thus, with a debated role as a physiological transmitter), β-alanine is an agonist next in activity to the cognate ligand glycine itself, for ]-sensitive inhibitory ]s (GlyRs) (the agonist order: glycine >> β-alanine > taurine >> alanine, <small>L</small>-serine > proline).<ref>''Encyclopedia of Life Sciences'' Amino Acid Neurotransmitters. Jeremy M Henley, 2001 John Wiley & Sons, Ltd. {{DOI|10.1038/npg.els.0000010}}, Article Online Posting Date: April 19, 2001</ref> | ||
| A high |
A high-potency ], called ], is derived from beta-alanine.<ref name="chemidplus">{{ChemID|102-66-9|Aspartic acid-beta-4-nitroanilide}}</ref> | ||
| ==References== | ==References== | ||
Revision as of 04:02, 27 January 2012
| |
| Names | |
|---|---|
| IUPAC name 3-Aminopropanoic acid | |
| Other names
β-Alanine 3-Aminopropionic acid | |
| Identifiers | |
| CAS Number | |
| 3D model (JSmol) | |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| DrugBank | |
| ECHA InfoCard | 100.003.215 
|
| IUPHAR/BPS | |
| KEGG | |
| PubChem CID | |
| UNII | |
| CompTox Dashboard (EPA) | |
InChI
| |
SMILES
| |
| Properties | |
| Chemical formula | C3H7NO2 |
| Molar mass | 89.093 g/mol |
| Appearance | Bipyramidal crystals |
| Density | 1.437 g/cm (19 °C) |
| Melting point | 207 °C decomp. |
| Solubility in water | soluble |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa).
 Y verify (what is ?)
Infobox references
| |
β-Alanine (or beta-alanine) is a naturally occurring beta amino acid, which is an amino acid in which the amino group is at the β-position from the carboxylate group (i.e., two atoms away, see Figure 1). The IUPAC name for β-alanine would be 3-aminopropanoic acid. Unlike its normal counterpart, α-alanine, β-alanine has no chiral center.
β-Alanine is not used in the biosynthesis of any major proteins or enzymes. It is formed in vivo by the degradation of dihydrouracil and carnosine. It is a component of the naturally occurring peptides carnosine and anserine and also of pantothenic acid (vitamin B5), which itself is a component of coenzyme A. Under normal conditions, β-alanine is metabolized into acetic acid.
β-Alanine is the rate-limiting precursor of carnosine, which is to say carnosine levels are limited by the amount of available β-alanine. Supplementation with β-alanine has been shown to increase the concentration of carnosine in muscles, decrease fatigue in athletes and increase total muscular work done.
Typically, studies have used supplementing strategies of multiple doses of 400 mg or 800 mg, administered at regular intervals for up to eight hours, over periods ranging from 4 to 10 weeks. After a 10-week supplementing strategy, the reported increase in intramuscular carnosine content was an average of 80.1% (range 18 to 205%).
L-Histidine, with a pKa of 6.1 is a relatively weak buffer over the physiological intramuscular pH range. However, when bound to other amino acids, this increases nearer to 6.8-7.0. In particular, when bound to β-alanine, the pKa value is 6.83, making this a very efficient intramuscular buffer. Furthermore, because of the position of the beta amino group, β-alanine dipeptides are not incorporated proteins and thus can be stored at relatively high concentrations (millimolar). Occurring at 17-25 mmol/kg (dry muscle), carnosine (β-alanyl-L-histidine) is an important intramuscular buffer, constituting 10-20% of the total buffering capacity in type I and II muscle fibres.
β-Alanine, provided in solution or as powder in gelatine capsules, however, causes paraesthesia when ingested in amounts above 10 mg per kg body weight (bwt). This is variable between individuals. Symptoms may be experienced by some individuals as mild even at 10 mg per kg bwt, in a majority as significant at 20 mg per kg bwt, and severe at 40 mg per kg bwt. However, an equivalent amount (equimolar) to 40 mg per kg bwt, ingested in the form of histidine containing dipeptides in chicken broth extract, did not cause paraesthesia.
It is probable that the paraesthesia, a form of neuropathic pain, results from high peak blood-plasma concentrations of β-alanine, since greater quantities, ingested in the form of the β-alanine/histidine (or methylhistidine)-containing dipeptides (i.e., carnosine and anserine) in meat, do not cause the same symptoms. In this case the β-alanine absorption profile is flattened but sustained for a longer period of time, whereas the β-alanine samples in the studies were administered as gelatine capsules containing powder. This resulted in the rapid rise of plasma concentrations, peaking within 30 to 45 minutes, and being eliminated after 90 to 120 minutes. The paraesthesia caused is no indication of efficacy, since the published studies undertaken so far have utilised doses of 400 mg or 800 mg at a time to avoid the paraesthesia. Furthermore, excretion of β-alanine in urine accounted for 0.60%(+/-0.09), 1.50%(+/-0.40), or 3.64%(+/-0.47) of the administered doses of 10, 20, or 40 mg per kg body weight, indicating greater losses occurring with increasing dosage.
Even though much weaker than glycine (and, thus, with a debated role as a physiological transmitter), β-alanine is an agonist next in activity to the cognate ligand glycine itself, for strychnine-sensitive inhibitory glycine receptors (GlyRs) (the agonist order: glycine >> β-alanine > taurine >> alanine, L-serine > proline).
A high-potency artificial sweetener, called suosan, is derived from beta-alanine.
References
- The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals (11th ed.). Merck. 1989. ISBN 091191028X., 196.
- Weast, Robert C., ed. (1981). CRC Handbook of Chemistry and Physics (62nd ed.). Boca Raton, Florida: CRC Press. p. C-83. ISBN 0-8493-0462-8..
- Derave W, Ozdemir MS, Harris R, Pottier A, Reyngoudt H, Koppo K, Wise JA, Achten E. (August 9, 2007). "Beta-alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters". J Appl Physiol. 103 (5): 1736. doi:10.1152/japplphysiol.00397.2007. PMID 17690198.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Hill CA, Harris RC, Kim HJ, Harris BD, Sale C, Boobis LH, Kim CK, Wise JA. (2007). "Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity". Amino Acids. 32 (2): 225–33. doi:10.1007/s00726-006-0364-4. PMID 16868650.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Harris, RC; Tallon, MJ; Dunnett, M; Boobis, L; Coakley, J; Kim, HJ; Fallowfield, JL; Hill, CA; Sale, C; et al. (2006). "The absorption of orally supplied β-alanine and its effect on muscle carnosine synthesis in human vastus lateralis". Amino Acids. 30 (3): 279–289. doi:10.1007/s00726-006-0299-9. PMID 16554972.
{{cite journal}}: Explicit use of et al. in:|first9=(help) - Bate-Smith, EC (1938). "The buffering of muscle in rigor: protein, phosphate and carnosine". Journal of Physiology. 92 (3): 336–343. PMC 1395289. PMID 16994977.
- Mannion, AF; Jakeman, PM; Dunnett, M; Harris, RC; Willan, PLT (1992). "Carnosine and anserine concentrations in the quadriceps femoris muscle of healthy humans". Eur. J. Appl. Physiol. 64: 47–50. doi:10.1007/BF00376439.
- Encyclopedia of Life Sciences Amino Acid Neurotransmitters. Jeremy M Henley, 2001 John Wiley & Sons, Ltd. doi:10.1038/npg.els.0000010, Article Online Posting Date: April 19, 2001
- Template:ChemID
External links
| Nucleotide metabolic intermediates | |||||||||||
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| purine metabolism |
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| pyrimidine metabolism |
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