View source for S-Adenosyl methionine

{{Short description|Chemical compound found in all domains of life with largely unexplored effects}}
{{DISPLAYTITLE:''S''-Adenosyl methionine}}
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| Name           = ''S''-Adenosyl methionine
| ImageFile      = S-adenosyl methionine.png
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| ImageFile1     = S-Adenosyl-Methionine.png
| ImageFile2     = S-adenosylmethionine spacefill.png
| SystematicName = (2''S'')-2-Amino-4-[(''S'')-<nowiki/>{[(2''S'',3''S'',4''R'',5''R'')-5-(4-amino-9''H''-purin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl}methylsulfaniumyl]butanoate
| OtherNames     = ''S''-Adenosyl-<small>L</small>-methionine; SAM-e; SAMe, [[AdoMet MTase|AdoMet]], Heparab (India),   ademethionine
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| SMILES = O=C(O)C(N)CC[S+](C)C[C@H]3O[C@@H](n2cnc1c(ncnc12)N)[C@H](O)[C@@H]3O
| MeSHName=S-Adenosylmethionine
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'''''S''-Adenosyl methionine''' ('''SAM'''), also known under the commercial names of '''SAMe''', '''SAM-e''', or '''AdoMet''', is a common [[cofactor (biochemistry)|cosubstrate]] involved in [[methyl group]] transfers, transsulfuration, and aminopropylation. Although these [[anabolic]] reactions occur throughout the body, most SAM is produced and consumed in the liver.<ref name=cantoni1952/> More than 40 methyl transfers from SAM are known, to various substrates such as [[nucleic acid]]s, [[protein]]s, [[lipid]]s and [[secondary metabolite]]s. It is made from [[adenosine triphosphate]] (ATP) and [[methionine]] by [[methionine adenosyltransferase]]. SAM was first discovered by [[Giulio Cantoni]] in 1952.<ref name=cantoni1952>{{cite journal | title=The Nature of the Active Methyl Donor Formed Enzymatically from L-Methionine and Adenosinetriphosphate | last=Cantoni | first = GL | journal=J Am Chem Soc | volume=74 | issue=11 | pages=2942–3 | year=1952 | doi=10.1021/ja01131a519 }}</ref>

In [[bacteria]], SAM is bound by the [[SAM riboswitch (S box leader)|SAM riboswitch]], which regulates [[gene]]s involved in methionine or [[cysteine]] biosynthesis. In [[eukaryotic]] cells, SAM serves as a regulator of a variety of processes including [[DNA]], [[tRNA]], and [[rRNA]] [[methylation]]; [[immune response]];<ref>{{Cite journal|last1=Ding|first1=Wei|last2=Smulan|first2=Lorissa J.|last3=Hou|first3=Nicole S.|last4=Taubert|first4=Stefan|last5=Watts|first5=Jennifer L.|last6=Walker|first6=Amy K.|date=2015-10-06|title=''S''-Adenosylmethionine Levels Govern Innate Immunity through Distinct Methylation-Dependent Pathways|journal=Cell Metabolism|volume=22|issue=4|pages=633–645|doi=10.1016/j.cmet.2015.07.013|pmc=4598287|pmid=26321661}}</ref> amino acid metabolism; [[Transsulfuration pathway|transsulfuration]]; and more. In plants, SAM is crucial to the biosynthesis of [[Ethylene as a plant hormone|ethylene]], an important [[plant hormone]] and signaling molecule.<ref>{{Cite journal|last1=Wang|first1=X.|last2=Oh|first2=M. W.|last3=Komatsu|first3=S.|date=2016-06-01|title=Characterization of ''S''-adenosylmethionine synthetases in soybean under flooding and drought stresses|journal=Biologia Plantarum|language=en|volume=60|issue=2|pages=269–278|doi=10.1007/s10535-016-0586-6|s2cid=15567646|issn=0006-3134|doi-access=free}}</ref>

==Structure==
''S''-Adenosyl methionine consists of the adenosyl group attached to the sulfur of methionine, providing it with a positive charge. It is synthesized from ATP and methionine by [[S-Adenosylmethionine synthetase enzyme|''S''-Adenosylmethionine synthetase enzyme]] through the following reaction:

: ATP + [[Methionine|<small>L</small>-methionine]] + H<small>2</small>O <math>\rightleftharpoons</math> [[phosphate]] + [[diphosphate]] + ''S''-adenosyl-<small>L</small>-methionine

The [[sulfonium]] functional group present in ''S''-adenosyl methionine is the center of its peculiar reactivity. Depending on the enzyme, ''S''-adenosyl methionine can be converted into one of three  products:
*adenosyl radical, which converts to deoxyadenosine (AdO): classic rSAM reaction, also cogenerates methionine
*[[S-adenosyl homocysteine|''S''-adenosyl homocysteine]], releasing methyl radical
*[[methylthioadenosine]] (SMT), homoalanine radical

== Biochemistry ==

=== SAM cycle ===
[[File:SN2 Mechanism of Methyltransferases.png|class=skin-invert-image|thumb|400px|The [[SN2 reaction|S<sub>N</sub>2]]-like methyl transfer reaction. Only the SAM cofactor and cytosine base are shown for simplicity.]]
The reactions that produce, consume, and regenerate SAM are called the SAM cycle. In the first step of this cycle, the SAM-dependent [[methylase]]s (EC 2.1.1) that use SAM as a substrate produce ''S''-adenosyl homocysteine as a product.<ref>{{cite journal |vauthors=Finkelstein J, Martin J |title=Homocysteine |journal=The International Journal of Biochemistry & Cell Biology|volume=32 |issue=4 |pages=385–9 |year=2000 |pmid=10762063 |doi=10.1016/S1357-2725(99)00138-7}}</ref> ''S''-Adenosyl homocysteine is a strong negative regulator of nearly all SAM-dependent methylases despite their biological diversity. This is hydrolysed to [[homocysteine]] and [[adenosine]] by [[Adenosylhomocysteinase|''S''-adenosylhomocysteine hydrolase]] [http://www.expasy.org/enzyme/3.3.1.1 EC 3.3.1.1] and the homocysteine recycled back to [[methionine]] through transfer of a methyl group from [[5-methyltetrahydrofolate]], by one of the two classes of [[methionine synthase]]s (i.e. [[cobalamin]]-dependent ([http://www.expasy.org/enzyme/2.1.1.13 EC 2.1.1.13]) or cobalamin-independent ([http://www.expasy.org/enzyme/2.1.1.14 EC 2.1.1.14])). This methionine can then be converted back to SAM, completing the cycle.<ref>{{cite journal |vauthors=Födinger M, Hörl W, Sunder-Plassmann G |title=Molecular biology of 5,10-methylenetetrahydrofolate reductase |journal=J Nephrol |volume=13 |issue=1 |pages=20–33 |date=Jan{{ndash}}Feb 2000 |pmid=10720211}}</ref> In the rate-limiting step of the SAM cycle, MTHFR (methylenetetrahydrofolate reductase) irreversibly reduces 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate.<ref>{{Cite journal|last1=Goyette|first1=P.|last2=Sumner|first2=J. S.|last3=Milos|first3=R.|last4=Duncan|first4=A. M.|last5=Rosenblatt|first5=D. S.|last6=Matthews|first6=R. G.|last7=Rozen|first7=R.|date=1994-06-01|title=Human methylenetetrahydrofolate reductase: isolation of cDNA, mapping and mutation identification|journal=Nature Genetics|volume=7|issue=2|pages=195–200|doi=10.1038/ng0694-195|issn=1061-4036|pmid=7920641|s2cid=23877329}}</ref>

=== Radical SAM enzymes ===
A large number of enzymes cleave SAM reductively to produce radicals:  [[deoxyadenosyl radical|5′-deoxyadenosyl 5′-radical]], methyl radical, and others.  These enzymes are called [[radical SAM]]s.  They all feature [[iron-sulfur cluster]] at their active sites.<ref>{{Cite journal | pmid = 21152342 | year = 2010 | last1 = Booker | first1 = SJ | last2 = Grove | first2 = TL | title = Mechanistic and functional versatility of radical SAM enzymes | volume = 2 | page = 52 | doi = 10.3410/B2-52 | pmc = 2996862 | journal = F1000 Biology Reports | doi-access = free }}</ref> Most enzymes with this capability share a region of sequence homology that includes the motif CxxxCxxC or a close variant. This sequence provides three cysteinyl thiolate ligands that bind to three of the four metals in the 4Fe-4S cluster.  The fourth Fe binds the SAM.

The radical intermediates generated by these enzymes perform a wide variety of unusual chemical reactions. Examples of radical SAM enzymes include [[spore photoproduct lyase]],  activases of [[pyruvate formate lyase]] and anaerobic sulfatases, [[lysine 2,3-aminomutase]], and various enzymes of cofactor biosynthesis, peptide modification, [[metalloprotein]] cluster formation, [[tRNA]] modification, lipid metabolism, etc. Some radical SAM enzymes use a second SAM as a methyl donor. Radical SAM enzymes are much more abundant in anaerobic bacteria than in aerobic organisms. They can be found in all domains of life and are largely unexplored. A recent bioinformatics study concluded that this family of enzymes includes at least 114,000 sequences including 65 unique reactions.<ref name=":0">{{Cite journal|title=Radical ''S''-Adenosylmethionine Enzymes in Human Health and Disease|journal = Annual Review of Biochemistry|volume = 85|pages = 485–514|last1=Landgraf|first1=Bradley J.|last2=McCarthy|first2=Erin L.|date=2016-06-13|language=en|doi=10.1146/annurev-biochem-060713-035504|pmid = 27145839|last3=Booker|first3=Squire J.}}</ref>

Deficiencies in radical SAM enzymes have been associated with a variety of diseases including [[Congenital heart defect|congenital heart disease]], [[amyotrophic lateral sclerosis]], and increased viral susceptibility.<ref name=":0" />

=== Polyamine biosynthesis ===
Another major role of SAM is in [[polyamine]] biosynthesis. Here, SAM is decarboxylated by [[adenosylmethionine decarboxylase]] ([http://www.expasy.org/enzyme/4.1.1.50 EC 4.1.1.50]) to form [[S-Adenosylmethioninamine|''S''-adenosylmethioninamine]]. This compound then donates its ''n''-propylamine group in the biosynthesis of polyamines such as [[spermidine]] and [[spermine]] from [[putrescine]].<ref>{{cite journal |author=Roje S |title=''S''-Adenosyl-L-methionine: beyond the universal methyl group donor |journal = [[Phytochemistry (journal)|Phytochemistry]] |volume=67 |issue=15 |pages=1686–98 |year=2006 |pmid=16766004 |doi=10.1016/j.phytochem.2006.04.019|bibcode=2006PChem..67.1686R }}</ref>

SAM is required for cellular growth and repair. It is also involved in the biosynthesis of several hormones and neurotransmitters that affect mood, such as [[epinephrine]].  [[Methyltransferase]]s are also responsible for the addition of methyl groups to the 2′ hydroxyls of the first and second [[nucleotide]]s next to the 5′ cap in [[messenger RNA]].<ref>{{cite journal |author=Loenen W |title=''S''-Adenosylmethionine: jack of all trades and master of everything? |journal=Biochem Soc Trans |volume=34 |issue=Pt 2 |pages=330–3 |year=2006 |pmid=16545107 |doi=10.1042/BST20060330}}</ref><ref>{{cite journal |vauthors=Chiang P, Gordon R, Tal J, Zeng G, Doctor B, Pardhasaradhi K, McCann P |title=''S''-Adenosylmethionine and methylation |journal=FASEB J |volume=10 |issue=4 |pages=471–80 |year=1996 |pmid=8647346|doi=10.1096/fasebj.10.4.8647346 |doi-access=free |s2cid=11214528 }}</ref>

== Therapeutic uses ==
===Osteoarthrtitis pain===
As of 2012, the evidence was inconclusive as to whether SAM can mitigate the pain of [[osteoarthritis]]; clinical trials that had been conducted were too small from which to generalize.<ref>{{cite journal|last1=Rutjes|first1=AW|last2=Nüesch|first2=E|last3=Reichenbach|first3=S|last4=Jüni|first4=P|title=''S''-Adenosylmethionine for osteoarthritis of the knee or hip.|journal=The Cochrane Database of Systematic Reviews|date=7 October 2009|volume=2009 |issue=4|pages=CD007321|doi=10.1002/14651858.CD007321.pub2|pmid=19821403|url=https://boris.unibe.ch/30335/1/Rutjes%20CochraneDatabaseSystRev%202009_CD007321.pdf|pmc=7061276}}</ref>

===Liver disease===
The SAM cycle has been closely tied to the liver since 1947 because people with [[Cirrhosis|alcoholic cirrhosis]] of the liver would accumulate large amounts of methionine in their blood.<ref>{{Cite journal|last=Mato|first=Jose M|year=1997|title=''S''-adenosylmethionine synthesis: Molecular mechanisms and clinical implications|journal=Pharmacology & Therapeutics|volume=73|issue=3|pages=265–280|doi=10.1016/s0163-7258(96)00197-0|pmid=9175157|hdl=10261/79246|hdl-access=free}}</ref> While multiple lines of evidence from laboratory tests on cells and [[animal models]] suggest that SAM might be useful to treat various [[liver disease]]s, as of 2012 SAM had not been studied in any large randomized placebo-controlled clinical trials that would allow an assessment of its efficacy and safety.<ref>{{cite journal|last1=Anstee|first1=QM|last2=Day|first2=CP|title=''S''-Adenosylmethionine (SAMe) therapy in liver disease: a review of current evidence and clinical utility|journal=Journal of Hepatology|date=November 2012|volume=57|issue=5|pages=1097–109|doi=10.1016/j.jhep.2012.04.041|pmid=22659519|url=http://www.journal-of-hepatology.eu/article/S0168-8278(12)00409-6/pdf|doi-access=free}}</ref><ref name="Lu2012rev">{{cite journal |last1=Lu |first1=SC |last2=Mato |first2=JM |date=October 2012 |title=''S''-Adenosylmethionine in liver health, injury, and cancer |journal=Physiological Reviews |volume=92 |issue=4 |pages=1515–42 |doi=10.1152/physrev.00047.2011 |pmc=3698976 |pmid=23073625}}</ref>

===Depression===
A 2016 Cochrane review concluded that for [[major depressive disorder]], "Given the absence of high quality evidence and the inability to draw firm conclusions based on that evidence, the use of SAMe for the treatment of depression in adults should be investigated further."<ref>{{cite journal|last1=Galizia|first1=I|last2=Oldani|first2=L|last3=Macritchie|first3=K|last4=Amari|first4=E|last5=Dougall|first5=D|last6=Jones|first6=TN|last7=Lam|first7=RW|last8=Massei|first8=GJ|last9=Yatham|first9=LN|last10=Young|first10=AH|title=''S''-Adenosyl methionine (SAMe) for depression in adults.|journal=The Cochrane Database of Systematic Reviews|date=10 October 2016|volume=2016|issue=10|pages=CD011286|doi=10.1002/14651858.CD011286.pub2|pmid=27727432|pmc=6457972}}</ref>

A 2020 systematic review found that it performed significantly better than placebo, and  had similar outcomes to other commonly used antidepressants ([[imipramine]] and [[escitalopram]]).<ref name="Cuomo Beccarini Crescenzi Bolognesi Goracci 2020 p.">{{cite journal | last1=Cuomo | first1=Alessandro | last2=Beccarini Crescenzi | first2=Bruno | last3=Bolognesi | first3=Simone | last4=Goracci | first4=Arianna | last5=Koukouna | first5=Despoina | last6=Rossi | first6=Rodolfo | last7=Fagiolini | first7=Andrea | title=S-Adenosylmethionine (SAMe) in major depressive disorder (MDD): a clinician-oriented systematic review | journal=Annals of General Psychiatry | publisher=Springer Science and Business Media LLC | volume=19 | issue=1 | date=2020-09-05 | issn=1744-859X | pmid=32939220 | pmc=7487540 | doi=10.1186/s12991-020-00298-z | page=50 | doi-access=free }}</ref>

=== Anti-cancer treatment ===
SAM has recently been shown to play a role in [[Epigenetics|epigenetic]] regulation. DNA methylation is a key regulator in epigenetic modification during mammalian cell development and differentiation. In mouse models, excess levels of SAM have been implicated in erroneous methylation patterns associated with diabetic neuropathy. SAM serves as the methyl donor in cytosine methylation, which is a key epigenetic regulatory process.<ref>{{Cite journal |last=Varela-Rey |first=Marta |year=2014 |title=''S''-Adenosylmethionine Levels Regulate the Schwann Cell DNA Methylome |journal=Neuron |volume=81 |issue=5 |pages=1024–1039 |doi=10.1016/j.neuron.2014.01.037 |pmc=3960855 |pmid=24607226}}</ref> Because of this impact on epigenetic regulation, SAM has been tested as an anti-cancer treatment. In many cancers, proliferation is dependent on having low levels of DNA methylation. In vitro addition in such cancers has been shown to remethylate oncogene promoter sequences and decrease the production of proto-oncogenes.<ref>{{Cite journal |last1=Schmidt |first1=Thomas |last2=Leha |first2=Andreas |last3=Salinas-Riester |first3=Gabriela |date=2016-12-31 |title=Treatment of prostate cancer cells with ''S''-adenosylmethionine leads to genome-wide alterations in transcription profiles |journal=Gene |volume=595 |issue=2 |pages=161–167 |doi=10.1016/j.gene.2016.09.032 |pmid=27688072}}</ref> In cancers such as colorectal cancer, aberrant global hypermethylation can inhibit promoter regions of tumor-suppressing genes. Contrary to the former information, colorectal cancers (CRCs) are characterized by global hypomethylation and promoter-specific DNA methylation.<ref>{{Cite journal |last=Tse |first=Janson |date=September 12, 2017 |title=Aberrant DNA Methylation in Colorectal Cancer: What Should We Target? |url=https://pubmed.ncbi.nlm.nih.gov/28958388/ |journal= Trends in Cancer|volume=3 |issue=10 |pages=698–712 |doi=10.1016/j.trecan.2017.08.003 |pmid=28958388 }}</ref>

== Pharmacokinetics ==

Oral SAM achieves peak plasma concentrations three to five hours after ingestion of an enteric-coated tablet (400–1000&nbsp;mg). The half-life is about 100 minutes.<ref name=BMC>
{{cite journal |vauthors=Najm WI, Reinsch S, Hoehler F, Tobis JS, Harvey PW |title=''S''-Adenosyl methionine (SAMe) versus celecoxib for the treatment of osteoarthritis symptoms: A double-blind cross-over trial. ISRCTN36233495 |journal=BMC Musculoskelet Disord |volume=5|page=6 |date=February 2004 |pmid=15102339 |pmc=387830 |doi=10.1186/1471-2474-5-6 |doi-access=free }}</ref>

==Availability in different countries==
In Canada, the UK,<ref name="mckie">{{Cite news |last=McKie |first=Robin |date=10 April 2022 |title=Biologists warn against toxic SAMe 'health' supplement |newspaper=The Observer |url=https://www.theguardian.com/society/2022/apr/10/biologists-warn-against-toxic-same-health-supplement}}</ref> and the United States, SAM is sold as a [[dietary supplement]] under the marketing name SAM-e (also spelled SAME or SAMe).<ref>{{Cite web |last=Woolston |first=Chris |date=31 December 2020 |title=What is SAM-e? |url=https://consumer.healthday.com/encyclopedia/depression-12/depression-news-176/what-is-sam-e-644990.html |website=HealthDay|archive-url=https://web.archive.org/web/20200812092019/https://consumer.healthday.com/encyclopedia/depression-12/depression-news-176/what-is-sam-e-644990.html |archive-date=2020-08-12 }}</ref> It was introduced in the US in 1999, after the [[Dietary Supplement Health and Education Act]] was passed in 1994.<ref name="Bottiglieri">{{cite journal |last1=Bottiglieri |first1=T |date=November 2002 |title=''S''-Adenosyl-L-methionine (SAMe): from the bench to the bedside--molecular basis of a pleiotrophic molecule |journal=The American Journal of Clinical Nutrition |volume=76 |issue=5 |pages=1151S–1157S |doi=10.1093/ajcn/76.5.1151S |pmid=12418493 |doi-access=free}}</ref>

It was introduced as a [[prescription drug]] in Italy in 1979, in Spain in 1985, and in Germany in 1989.<ref name="Bottiglieri" /> As of 2012, it was sold as a prescription drug in Russia, India, China, Italy, Germany, Vietnam, and Mexico.<ref name="Lu2012rev" />

== Adverse effects ==
Gastrointestinal disorder, [[dyspepsia]] and [[anxiety]] can occur with SAM consumption.<ref name="BMC" /> Long-term effects are unknown. SAM is a weak DNA-[[Alkylation|alkylating]] agent.<ref>{{cite journal |vauthors=Rydberg B, Lindahl T |year=1982 |title=Nonenzymatic methylation of DNA by the intracellular methyl group donor ''S''-adenosyl-L-methionine is a potentially mutagenic reaction |journal=EMBO J. |volume=1 |issue=2 |pages=211–6 |doi=10.1002/j.1460-2075.1982.tb01149.x |pmc=553022 |pmid=7188181}}</ref>

Another reported side effect of SAM is [[insomnia]]; therefore, the supplement is often taken in the morning. Other reports of mild side effects include lack of appetite, constipation, nausea, dry mouth, sweating, and anxiety/nervousness, but in placebo-controlled studies, these side effects occur at about the same incidence in the placebo groups.{{medical citation needed|date=November 2016}}

===Interactions and contraindications===
Taking SAM at the same time as some drugs may increase the risk of [[serotonin syndrome]], a potentially dangerous condition caused by having too much serotonin. These drugs include, but are certainly not limited to, [[dextromethorphan]] (Robitussin), [[meperidine]] (Demerol), [[pentazocine]] (Talwin), and [[tramadol]] (Ultram).<ref name="Mayo Clinic">{{cite web|title=SAMe - Mayo Clinic|website=[[Mayo Clinic]] |url=https://www.mayoclinic.org/drugs-supplements-same/art-20364924}}</ref>

SAM can also interact with many antidepressant medications — including [[tryptophan]] and the herbal medicine ''[[Hypericum perforatum]]'' (St. John's wort) — increasing the potential for serotonin syndrome or other side effects, and may reduce the effectiveness of [[levodopa]] for Parkinson's disease.<ref name="NCCIH">{{cite web|title=''S''-Adenosyl-L-Methionine (SAMe): In Depth|url=https://www.nccih.nih.gov/health/sadenosyllmethionine-same-in-depth|publisher=National Center for Complementary and Integrative Health (NCCIH)|language=en|date=January 11, 2017}}</ref> SAM can increase the risk of manic episodes in people who have [[bipolar disorder]].<ref name="NCCIH" />

=== Toxicity ===
A 2022 study concluded that SAMe could be toxic. Jean-Michel Fustin of [[Manchester University]] said that the researchers found that excess SAMe breaks down into [[adenine]] and [[methylthioadenosine]] in the body, both producing the [[paradoxical effect]] of inhibiting methylation. This was found in [[laboratory mice]], causing harm to health, and in ''[[in vitro]]'' tests on human cells.<ref name="fukumoto">{{cite journal |last1=Fukumoto |first1=Kazuki |last2=Ito |first2=Kakeru |last3=Saer |first3=Benjamin |last4=Taylor |first4=George |last5=Ye |first5=Shiqi |last6=Yamano |first6=Mayu |last7=Toriba |first7=Yuki |last8=Hayes |first8=Andrew |last9=Okamura |first9=Hitoshi |last10=Fustin |first10=Jean-Michel |date=5 April 2022 |title=Excess S-adenosylmethionine inhibits methylation via catabolism to adenine |journal=[[Communications Biology]] |publisher=[[Nature Communications|Nature Publishing Group]] |volume=5 |issue=1 |page= 313|doi=10.1038/s42003-022-03280-5 |issn=2399-3642 |pmid=35383287 |pmc=8983724 |doi-access=free|hdl=2433/269415 |hdl-access=free }}</ref><ref name="mckie" />

== See also ==
* [[DNA methyltransferase]]
* [[SAM riboswitch (S-box leader)|SAM-I riboswitch]]
* [[SAM-II riboswitch]]
* [[SMK box riboswitch|SAM-III riboswitch]]
* [[SAM-IV riboswitch]]
* [[SAM-V riboswitch]]
* [[SAM-VI riboswitch]]
* [[List of investigational antidepressants]]

==References==
{{Reflist|2}}

== External links ==
* {{EINECSLink|249-946-8}}
* {{cite journal |doi=10.1186/1471-244X-4-38 |year=2004 |last1=Shippy |first1=R Andrew |last2=Mendez |first2=Douglas |last3=Jones |first3=Kristina |last4=Cergnul |first4=Irene |last5=Karpiak |first5=Stephen E |journal=BMC Psychiatry |volume=4 |page=38 |pmid=15538952 |title=''S''-Adenosylmethionine (SAM-e) for the treatment of depression in people living with HIV/AIDS |pmc=535560 |doi-access=free }}

{{Enzyme cofactors}}
{{Amino acid metabolism intermediates}}{{Antidepressants}}
{{Authority control}}

{{DEFAULTSORT:Adenosyl Methionine, S-}}
[[Category:Alpha-Amino acids]]
[[Category:Coenzymes]]
[[Category:Dietary supplements]]
[[Category:Biology of bipolar disorder]]
[[Category:Psychopharmacology]]
[[Category:Sulfonium compounds]]