View source for Coenzyme Q10

{{Short description|Biochemical cofactor and antioxidant}}
{{cs1 config|name-list-style=vanc|display-authors=6}}
{{Use American English|date=April 2024}}
{{Use dmy dates|date=October 2022}}
{{chembox
| Name = Coenzyme Q<sub>10</sub>
| Watchedfields = changed
| verifiedrevid = 477001960
| ImageFile = Coenzyme_Q10.svg
| PIN = 2-[(2''E'',6''E'',10''E'',14''E'',18''E'',22''E'',26''E'',30''E'',34''E'')-3,7,11,15,19,23,27,31,35,39-Decamethyltetraconta-2,6,10,14,18,22,26,30,34,38-decaen-1-yl]-5,6-dimethoxy-3-methylcyclohexa-2,5-diene-1,4-dione
| OtherNames =
{{plainlist|1=
* In general: Ubiquinone, coenzyme Q, CoQ, vitamin Q (misnomer: being not required it cannot be a [[vitamin]])
* This form: ubidecarenone,
Q<sub>10</sub>, CoQ<sub>10</sub> {{IPAc-en|ˌ|k|oʊ|ˌ|k|juː|ˈ|t|ɛ|n}}}}
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 4445197
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 454801
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = EJ27X76M46
| InChI = 1/C59H90O4/c1-44(2)24-15-25-45(3)26-16-27-46(4)28-17-29-47(5)30-18-31-48(6)32-19-33-49(7)34-20-35-50(8)36-21-37-51(9)38-22-39-52(10)40-23-41-53(11)42-43-55-54(12)56(60)58(62-13)59(63-14)57(55)61/h24,26,28,30,32,34,36,38,40,42H,15-23,25,27,29,31,33,35,37,39,41,43H2,1-14H3/b45-26+,46-28+,47-30+,48-32+,49-34+,50-36+,51-38+,52-40+,53-42+
| InChIKey = ACTIUHUUMQJHFO-UPTCCGCDBK
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C59H90O4/c1-44(2)24-15-25-45(3)26-16-27-46(4)28-17-29-47(5)30-18-31-48(6)32-19-33-49(7)34-20-35-50(8)36-21-37-51(9)38-22-39-52(10)40-23-41-53(11)42-43-55-54(12)56(60)58(62-13)59(63-14)57(55)61/h24,26,28,30,32,34,36,38,40,42H,15-23,25,27,29,31,33,35,37,39,41,43H2,1-14H3/b45-26+,46-28+,47-30+,48-32+,49-34+,50-36+,51-38+,52-40+,53-42+
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = ACTIUHUUMQJHFO-UPTCCGCDSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 303-98-0
| PubChem = 5281915
| KEGG = C11378
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 46245
| SMILES = O=C1/C(=C(\C(=O)C(\OC)=C1\OC)C)C\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)CC\C=C(/C)C
}}
|Section2={{Chembox Properties
| C=59 | H=90 | O=4
| Appearance = yellow or orange solid
| Density =
| MeltingPtC = 48–52
| BoilingPt =
| Solubility = insoluble
 }}
|Section6={{Chembox Pharmacology
| ATCCode_prefix = C01
| ATCCode_suffix = EB09
}}
|Section7={{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
 }}
|Section8={{Chembox Related
| OtherFunction = [[1,4-Benzoquinone]]<br />[[Plastoquinone]]<br />[[Ubiquinol]]
| OtherFunction_label = [[quinone]]s
 }}
}}

'''Coenzyme Q''' ('''CoQ''' {{IPAc-en|ˌ|k|oʊ|k|j|uː}}), also known as '''ubiquinone''', is a naturally occurring [[Cofactor (biochemistry)|biochemical cofactor]] (coenzyme) and an [[antioxidant]] produced by the human body. The human body mainly produces the form known as '''coenzyme Q<sub>10</sub>''' (CoQ<sub>10</sub>, ubidecarenone), but other forms exist.<ref name="lpi">{{cite web |title=Coenzyme Q10 |url=https://lpi.oregonstate.edu/mic/dietary-factors/coenzyme-Q10 |publisher=Micronutrient Information Center, Linus Pauling Institute, Oregon State University |access-date=13 April 2024 |date=2018 |archive-date=15 March 2024 |archive-url=https://web.archive.org/web/20240315190507/https://lpi.oregonstate.edu/mic/dietary-factors/coenzyme-Q10 |url-status=live }}</ref><ref name="sood">{{cite web |vauthors=Sood B, Preeti Patel P, Keenaghan M |title=Coenzyme Q10 |url=https://www.ncbi.nlm.nih.gov/books/NBK531491/ |publisher=StatPearls, US National Library of Medicine |access-date=17 April 2024 |date=30 January 2024 |pmid=30285386 |archive-date=2 October 2023 |archive-url=https://web.archive.org/web/20231002122139/https://ncbi.nlm.nih.gov/books/NBK531491/ |url-status=live }}</ref><ref name="nccih">{{cite web |title=Coenzyme Q10 |url=https://www.nccih.nih.gov/health/coenzyme-q10 |publisher=National Center for Complementary and Integrative Health, US National Institutes of Health |access-date=13 April 2024 |date=January 2019 |archive-date=4 April 2024 |archive-url=https://web.archive.org/web/20240404222534/https://www.nccih.nih.gov/health/coenzyme-q10 |url-status=live }}</ref> CoQ is used by and found in many organisms, including animals and bacteria. As a result, it can also be obtained from dietary sources, such as meat, fish, seed oils, vegetables, and [[dietary supplement]]s.<ref name=lpi/><ref name=sood/>

CoQ plays a role in [[mitochondria]]l [[oxidative phosphorylation]], aiding in the production of [[adenosine triphosphate]] (ATP), which is involved in energy transfer within cells.<ref name=lpi/> The structure of CoQ<sub>10</sub> consists of a benzoquinone moiety and an isoprenoid side chain, with the "10" referring to the number of [[Isoprene|isoprenyl]] chemical subunits in its tail.<ref name="pmid36768907">{{cite journal | vauthors = Mantle D, Lopez-Lluch G, Hargreaves IP | title = Coenzyme Q10 Metabolism: A Review of Unresolved Issues | journal = International Journal of Molecular Sciences | volume = 24 | issue = 3 | page = 2585 | date = January 2023 | pmid = 36768907 | pmc = 9916783 | doi = 10.3390/ijms24032585 | doi-access = free }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref><ref name="Kadian-2022">{{cite journal|doi=10.1007/s40495-021-00273-6 |title=The Impact of Coenzyme Q10 on Neurodegeneration: A Comprehensive Review |date=2022 |journal=Current Pharmacology Reports |volume=8 |pages=1–19 | vauthors = Kadian M, Sharma G, Pandita S, Sharma K, Shrivasatava K, Saini N, Kumar A }}</ref><ref name="pmid34064686">{{cite journal | vauthors = Mantle D, Heaton RA, Hargreaves IP | title = Coenzyme Q10 and Immune Function: An Overview | journal = Antioxidants | volume = 10 | issue = 5 | page = 759 | date = May 2021 | pmid = 34064686 | pmc = 8150987 | doi = 10.3390/antiox10050759 | doi-access = free }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref>

Although a ubiquitous molecule in human tissues, CoQ<sub>10</sub> is not a dietary [[nutrient]] and does not have a [[Dietary Reference Intake|recommended intake level]], and its use as a supplement is not [[approved drug|approved]] in the United States for any health or anti-disease effect.<ref name=lpi/><ref name=sood/>

==Biological functions==
{{See also|Q cycle}}
CoQ<sub>10</sub> is a component of the mitochondrial [[electron transport chain]] (ETC), where it plays a role in oxidative phosphorylation, a process required for the biosynthesis of adenosine triphosphate, the primary energy source of cells.<ref name=lpi/><ref name="pmid34064686"/><ref name="pmid34596729">{{cite journal |vauthors=Pradhan N, Singh C, Singh A |title=Coenzyme Q10 a mitochondrial restorer for various brain disorders |journal=Naunyn Schmiedebergs Arch Pharmacol |volume=394 |issue=11 |pages=2197–2222 |date=November 2021 |pmid=34596729 |doi=10.1007/s00210-021-02161-8}}</ref>

CoQ<sub>10</sub> is a [[Lipophilicity|lipophilic]] molecule that is located in all biological membranes of human body and serves as a component for the synthesis of ATP and is a life-sustaining cofactor for the three complexes ([[complex I]], [[complex II]], and [[complex III]]) of the ETC in the mitochondria.<ref name=lpi/><ref name="Kadian-2022"/> CoQ<sub>10</sub> has a role in the transport of [[proton]]s across [[lysosome|lysosomal]] membranes to regulate pH in lysosome functions.<ref name=lpi/>

The mitochondrial oxidative phosphorylation process occurs in the inner mitochondrial membrane of eukaryotic cells.<ref name=lpi/> This membrane is highly folded into structures called cristae, which increase the surface area available for oxidative phosphorylation. CoQ<sub>10</sub> plays a role in this process as an essential cofactor of the ETC located in the inner mitochondrial membrane and serves the following functions:<ref name=lpi/><ref name="pmid34596729"/>
* electron transport in the mitochondrial ETC, by shuttling electrons from mitochondrial complexes like [[nicotinamide adenine dinucleotide]] (NADH), [[ubiquinone reductase]] (complex I), and succinate ubiquinone reductase (complex II), the fatty acids and branched-chain amino acids oxidation (through flavin-linked dehydrogenases) to [[Ubiquinol--cytochrome-c reductase|ubiquinol–cytochrome-c reductase]] (complex III) of the ETC:<ref name=lpi/><ref name="pmid34596729"/> CoQ<sub>10</sub> participates in fatty acid and glucose metabolism by transferring electrons generated from the reduction of fatty acids and glucose to electron acceptors;<ref name="pmid33291255">{{cite journal |vauthors=Manzar H, Abdulhussein D, Yap TE, Cordeiro MF |title=Cellular Consequences of Coenzyme Q10 Deficiency in Neurodegeneration of the Retina and Brain |journal=Int J Mol Sci |volume=21 |issue=23 |date=December 2020 |page=9299 |pmid=33291255 |pmc=7730520 |doi=10.3390/ijms21239299 |doi-access=free}}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref>
* antioxidant activity as a lipid-soluble antioxidant together with [[vitamin E]], scavenging [[reactive oxygen species]] and protecting cells against oxidative stress,<ref name=lpi/><ref name="pmid34064686"/> inhibiting the oxidation of proteins, DNA, and use of vitamin E.<ref name=lpi/><ref name="pmid32349341">{{cite journal |vauthors=Di Lorenzo A, Iannuzzo G, Parlato A, Cuomo G, Testa C, Coppola M, D'Ambrosio G, Oliviero DA, Sarullo S, Vitale G, Nugara C, Sarullo FM, Giallauria F |title=Clinical Evidence for Q10 Coenzyme Supplementation in Heart Failure: From Energetics to Functional Improvement |journal=J Clin Med |volume=9 |issue=5 |date=April 2020 |page=1266 |pmid=32349341 |pmc=7287951 |doi=10.3390/jcm9051266 | doi-access=free}}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref>

==Biochemistry==
{{Expert needed|biochemistry|talk=Biological function|date=April 2024}}
Coenzymes Q is a [[cofactor (biochemistry)|coenzyme]] family that is [[ubiquitous]] in animals and many [[Pseudomonadota]],<ref name="pmid20599680">{{cite journal | vauthors = Nowicka B, Kruk J | title = Occurrence, biosynthesis and function of isoprenoid quinones | journal = Biochimica et Biophysica Acta (BBA) - Bioenergetics | volume = 1797 | issue = 9 | pages = 1587–1605 | date = September 2010 | pmid = 20599680 | doi = 10.1016/j.bbabio.2010.06.007 | doi-access = free }}</ref> a group of gram-negative bacteria. The fact that the coenzyme is ubiquitous gives the origin of its other name, ubiquinone.<ref name=lpi/><ref name=sood/><ref name="pubchem-Ubidecarenone">{{Include-USGov|agency=[[National Center for Biotechnology Information]]|title=Ubidecarenone |url=https://pubchem.ncbi.nlm.nih.gov/compound/5281915 | work = PubChem | publisher = US National Library of Medicine |access-date=4 April 2024 |date=30 March 2024}}</ref> In humans, the most common form of coenzymes Q is coenzyme Q<sub>10</sub>, also called CoQ<sub>10</sub> ({{IPAc-en|ˌ|k|oʊ|k|j|uː|ˈ|t|ɛ|n}}) or ubiquinone-10.<ref name=lpi/>

Coenzyme Q<sub>10</sub> is a [[1,4-Benzoquinone|1,4-benzoquinone]], in which "Q" refers to the [[quinone]] chemical group and "10" refers to the number of [[isoprene|isoprenyl]] chemical subunits (shown enclosed in brackets in the diagram) in its tail.<ref name=lpi/> In natural ubiquinones, there are from six to ten subunits in the tail, with humans having a tail of 10 isoprene units (50 carbon atoms) connected to its benzoquinone "head".<ref name=lpi/>

This family of fat-soluble substances is present in all respiring [[Eukaryote|eukaryotic]] cells, primarily in the mitochondria.<ref name=lpi/> Ninety-five percent of the human body's energy is generated this way.<ref name="pmid7599208">{{cite journal | vauthors = Ernster L, Dallner G | title = Biochemical, physiological and medical aspects of ubiquinone function | journal = Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease | volume = 1271 | issue = 1 | pages = 195–204 | date = May 1995 | pmid = 7599208 | doi = 10.1016/0925-4439(95)00028-3 | doi-access = free }}</ref> Organs with the highest energy requirements—such as the [[heart]], [[liver]], and [[kidney]]—have the highest CoQ<sub>10</sub> concentrations.<ref name="pmid2599795">{{cite journal | vauthors = Okamoto T, Matsuya T, Fukunaga Y, Kishi T, Yamagami T | title = Human serum ubiquinol-10 levels and relationship to serum lipids | journal = International Journal for Vitamin and Nutrition Research | volume = 59 | issue = 3 | pages = 288–292 | year = 1989 | pmid = 2599795 }}</ref><ref name="pmid1586151">{{cite journal | vauthors = Aberg F, Appelkvist EL, Dallner G, Ernster L | title = Distribution and redox state of ubiquinones in rat and human tissues | journal = Archives of Biochemistry and Biophysics | volume = 295 | issue = 2 | pages = 230–234 | date = June 1992 | pmid = 1586151 | doi = 10.1016/0003-9861(92)90511-T }}</ref><ref name="pmid8288904">{{cite journal | vauthors = Shindo Y, Witt E, Han D, Epstein W, Packer L | title = Enzymic and non-enzymic antioxidants in epidermis and dermis of human skin | journal = The Journal of Investigative Dermatology | volume = 102 | issue = 1 | pages = 122–124 | date = January 1994 | pmid = 8288904 | doi = 10.1111/1523-1747.ep12371744 | doi-access =free  }}</ref><ref name="Žmitek-2008">{{cite journal|vauthors=Žmitek J, ŽMitek K, Pravs I|title=Improving the bioavailability of coenzyme q10 from theory to practice|year=2008|journal=Agro Food Industry Hi-Tech|url=https://www.scopus.com/inward/record.uri?eid=2-s2.0-53849139131&partnerID=40&md5=25ac2ff16eec9fc4a8b52430316bfbd8|access-date=5 April 2024|archive-date=23 April 2024|archive-url=https://web.archive.org/web/20240423075336/https://www.scopus.com/record/display.uri?eid=2-s2.0-53849139131&origin=inward&txGid=4f4a035686dfee6b6fbde3099b06b518|url-status=live}}</ref>

There are three [[redox]] states of CoQ: fully oxidized (''ubi''quinone), [[Semiquinone|''semi''quinone]] (''ubisemi''quinone), and fully [[Organic redox reaction|reduced]] ([[ubiquinol]]).<ref name=lpi/> The capacity of this molecule to act as a two-electron carrier (moving between the quinone and quinol form) and a one-electron carrier (moving between the semiquinone and one of these other forms) is central to its role in the electron transport chain due to the [[iron–sulfur cluster]]s that can only accept one electron at a time and as a free radical–scavenging antioxidant.<ref name=lpi/><ref name="pubchem-Ubidecarenone"/>

==Deficiency==
There are two major pathways of deficiency of CoQ<sub>10</sub> in humans: reduced [[biosynthesis]], and increased use by the body.<ref name="pmid25091424">{{cite journal |vauthors=Desbats MA, Lunardi G, Doimo M, Trevisson E, Salviati L |title=Genetic bases and clinical manifestations of coenzyme Q10 (CoQ 10) deficiency |journal=J Inherit Metab Dis |volume=38 |issue=1 |pages=145–56 |date=January 2015 |pmid=25091424 |doi=10.1007/s10545-014-9749-9 |url=}}</ref> Biosynthesis is the major source of CoQ<sub>10</sub>. Biosynthesis requires at least 15 [[gene]]s, and mutations in any of them can cause CoQ deficiency.<ref name="pmid25091424"/> CoQ<sub>10</sub> levels also may be affected by other genetic defects (such as mutations of [[mitochondrial DNA]], ''[[ETFDH]]'', ''[[APTX]]'', ''[[FXN]]'', and ''[[BRAF (gene)|BRAF]]'', genes that are not directly related to the CoQ<sub>10</sub> biosynthetic process).<ref name="pmid25091424"/> Some of these, such as mutations in ''[[COQ6]]'', can lead to serious diseases such as steroid-resistant [[nephrotic syndrome]] with sensorineural [[deafness]].<ref>{{cite journal|doi=10.1172/JCI45693 |title=COQ6 mutations in human patients produce nephrotic syndrome with sensorineural deafness |date=2011 |journal=Journal of Clinical Investigation |volume=121 |issue=5 |pages=2013–2024 |pmid=21540551 |pmc=3083770 |vauthors = Heeringa SF, Chernin G, Chaki M, Zhou W, Sloan AJ, Ji Z, Xie LX, Salviati L, Hurd TW, Vega-Warner V, Killen PD, Raphael Y, Ashraf S, Ovunc B, Schoeb DS, McLaughlin HM, Airik R, Vlangos CN, Gbadegesin R, Hinkes B, Saisawat P, Trevisson E, Doimo M, Casarin A, Pertegato V, Giorgi G, Prokisch H, Rötig A, Nürnberg G, Becker C }}</ref><ref>{{cite journal|doi=10.1002/jmd2.12068 |title=''COQ6'' mutation in patients with nephrotic syndrome, sensorineural deafness, and optic atrophy |date=2020 |journal=JIMD Reports |volume=54 |issue=1 |pages=37–44 |pmid=32685349 |pmc=7358665 | vauthors = Justine Perrin R, Rousset-Rouvière C, Garaix F, Cano A, Conrath J, Boyer O, Tsimaratos M }}</ref><ref>{{cite web | url=https://www.ncbi.nlm.nih.gov/medgen/886260 | title=Nephrotic Syndrome - COQ6 Associated (Concept Id: C4054393) - MedGen - NCBI | access-date=6 April 2024 | archive-date=6 April 2024 | archive-url=https://web.archive.org/web/20240406102811/https://www.ncbi.nlm.nih.gov/medgen/886260 | url-status=live }}</ref>

===Assessment===
Although CoQ<sub>10</sub> may be measured in [[blood plasma]], these measurements reflect dietary intake rather than tissue status. Currently, most clinical centers measure CoQ<sub>10</sub> levels in cultured skin [[fibroblast]]s, muscle [[biopsy|biopsies]], and blood mononuclear cells.<ref name="pmid21844807">{{cite journal | vauthors = Trevisson E, DiMauro S, Navas P, Salviati L | title = Coenzyme Q deficiency in muscle | journal = Current Opinion in Neurology | volume = 24 | issue = 5 | pages = 449–456 | date = October 2011 | pmid = 21844807 | doi = 10.1097/WCO.0b013e32834ab528 | hdl-access = free | hdl = 10261/129020 }}</ref> Culture fibroblasts can be used also to evaluate the rate of endogenous CoQ<sub>10</sub> biosynthesis, by measuring the uptake of [[carbon-14|<sup>14</sup>C]]-[[isotopic labeling|labeled]] [[p-Hydroxybenzoic acid|''p''-hydroxybenzoate]].<ref name="pmid18387363">{{cite journal | vauthors = Montero R, Sánchez-Alcázar JA, Briones P, Hernández AR, Cordero MD, Trevisson E, Salviati L, Pineda M, García-Cazorla A, Navas P, Artuch R | title = Analysis of coenzyme Q10 in muscle and fibroblasts for the diagnosis of CoQ<sub>10</sub> deficiency syndromes | journal = Clinical Biochemistry | volume = 41 | issue = 9 | pages = 697–700 | date = June 2008 | pmid = 18387363 | doi = 10.1016/j.clinbiochem.2008.03.007 | hdl-access = free | hdl = 11577/2447079 }}</ref>

CoQ<sub>10</sub> is studied as an adjunctive therapy to reduce inflammation in [[periodontitis]].<ref name="pmid37592831">{{cite journal |vauthors=Fawzy El-Sayed KM, Cosgarea R, Sculean A, Doerfer C |title=Can vitamins improve periodontal wound healing/regeneration? |journal=Periodontol 2000 |volume=94 |issue=1 |pages=539–602 |date=February 2024 |pmid=37592831 |doi=10.1111/prd.12513 |url=|doi-access=free }}</ref>

===Statins===
Although statins may reduce CoQ<sub>10</sub> in the blood it is unclear if they reduce CoQ<sub>10</sub> in muscle.<ref name="pmid28546301"/> Evidence does not support that supplementation improves statin side effects.<ref name="pmid28546301">{{cite journal | vauthors = Tan JT, Barry AR | title = Coenzyme Q10 supplementation in the management of statin-associated myalgia | journal = American Journal of Health-System Pharmacy | volume = 74 | issue = 11 | pages = 786–793 | date = June 2017 | pmid = 28546301 | doi = 10.2146/ajhp160714 | s2cid = 3825396 | doi-access = free }}</ref><ref>{{Cite journal |last1=Kennedy |first1=Cormac |last2=Köller |first2=Yasmin |last3=Surkova |first3=Elena |date=2020-04-01 |title=Effect of Coenzyme Q10 on statin-associated myalgia and adherence to statin therapy: A systematic review and meta-analysis |journal=Atherosclerosis |language=en |volume=299 |pages=1–8 |doi=10.1016/j.atherosclerosis.2020.03.006 |pmid=32179207 |doi-access=free }}</ref>

==Chemical properties==
The oxidized structure of CoQ<sub>10</sub> is shown below. The various kinds of coenzyme Q may be distinguished by the number of [[isoprenoid]] subunits in their [[Side chain|side-chains]]. The most common coenzyme Q in human mitochondria is CoQ<sub>10</sub>.<ref name=lpi/> Q refers to the quinone head and "10" refers to the number of isoprene repeats in the tail. The molecule below has three isoprenoid units and would be called Q<sub>3</sub>.
:[[File:Unibuinone3.svg|none|300px|alt=Coenzyme Q<sub>3</sub>]]

In its pure state, it is an orange-colored lipophile powder and has no taste or odor.<ref name="pubchem-Ubidecarenone"/>

==Biosynthesis==
Biosynthesis occurs in most human tissue. There are three major steps:
# Creation of the [[benzoquinone]] structure (using [[phenylalanine]] or [[tyrosine]], via [[4-hydroxybenzoate]])
# Creation of the [[isoprene]] side chain (using [[acetyl-CoA]])
# The joining or [[condensation reaction|condensation]] of the above two structures

The initial two reactions occur in [[mitochondria]], the [[endoplasmic reticulum]], and [[peroxisome]]s, indicating multiple sites of synthesis in animal cells.<ref name="pmid20494114">{{cite journal | vauthors = Bentinger M, Tekle M, Dallner G | title = Coenzyme Q--biosynthesis and functions | journal = Biochemical and Biophysical Research Communications | volume = 396 | issue = 1 | pages = 74–79 | date = May 2010 | pmid = 20494114 | doi = 10.1016/j.bbrc.2010.02.147 | bibcode = 2010BBRC..396...74B }}</ref>

An important enzyme in this pathway is [[HMG-CoA reductase]], usually a target for intervention in cardiovascular complications. The "statin" family of cholesterol-reducing medications inhibits HMG-CoA reductase. One possible side effect of statins is decreased production of CoQ<sub>10</sub>, which may be connected to the development of [[myopathy]] and [[rhabdomyolysis]]. However, the role statins play in CoQ deficiency is controversial. Although statins reduce blood levels of CoQ, studies on the effects of muscle levels of CoQ are yet to come. 

Genes involved include ''[[PDSS1]]'', ''[[PDSS2]]'', ''[[COQ2]]'', and ''[[ADCK3]]'' (''COQ8'', ''CABC1'').<ref name="Espinós-2009">{{Cite book | vauthors = Espinós C, Felipo V, Palau F |url=https://books.google.com/books?id=uxQ_pjKNhE8C&pg=PA122 |title=Inherited Neuromuscular Diseases: Translation from Pathomechanisms to Therapies |date=2009 |publisher=Springer |isbn=978-90-481-2812-9 |pages=122ff |access-date=4 January 2011}}</ref>

Organisms other than humans produce the benzoquinone and isoprene structures from somewhat different source chemicals. For example, the bacteria ''[[E. coli]]'' produces the former from [[chorismate]] and the latter from a non-[[mevalonate]] source. The common yeast ''[[S. cerevisiae]]'', however, derives the former from either chorismate or tyrosine and the latter from [[mevalonate]]. Most organisms share the common 4-hydroxybenzoate intermediate, yet again uses different steps to arrive at the "Q" structure.<ref name="pmid11583838">{{cite journal | vauthors = Meganathan R | title = Ubiquinone biosynthesis in microorganisms | journal = FEMS Microbiology Letters | volume = 203 | issue = 2 | pages = 131–139 | date = September 2001 | pmid = 11583838 | doi = 10.1111/j.1574-6968.2001.tb10831.x | doi-access = free }}</ref>

==Dietary supplement==
Although neither a [[prescription drug]] nor an [[essential nutrient]], CoQ<sub>10</sub> is commonly used as a dietary supplement with the intent to prevent or improve disease conditions, such as cardiovascular disorders.<ref name=sood/><ref name="arenas">{{cite journal | vauthors = Arenas-Jal M, Suñé-Negre JM, García-Montoya E | title = Coenzyme Q10 supplementation: Efficacy, safety, and formulation challenges | journal = Comprehensive Reviews in Food Science and Food Safety | volume = 19 | issue = 2 | pages = 574–594 | date = March 2020 | pmid = 33325173 | doi = 10.1111/1541-4337.12539 | hdl-access = free | hdl = 2445/181270 }}</ref> Despite its significant role in the body, it is not used as a drug to treat any specific disease.<ref name=lpi/><ref name=sood/><ref name=nccih/>

Nevertheless, CoQ<sub>10</sub> is widely available as an over-the-counter dietary supplement and is recommended by some healthcare professionals, despite a lack of definitive scientific evidence supporting these recommendations,<ref name=lpi/><ref name=nccih/> especially when it comes to cardiovascular diseases.<ref name="pmid36852817">{{cite journal |vauthors=Bjørklund G, Semenova Y, Gasmi A, Indika NR, Hrynovets I, Lysiuk R, Lenchyk L, Uryr T, Yeromina H, Peana M |title=Coenzyme Q10 for Enhancing Physical Activity and Extending the Human Life Cycle |journal=Curr Med Chem |volume=31 |issue=14 |pages=1804–1817 |date=2024 |pmid=36852817 |doi=10.2174/0929867330666230228103913}}</ref>

==Regulation and composition==
CoQ<sub>10</sub> is not approved by the U.S. [[Food and Drug Administration]] (FDA) for the treatment of any medical condition.<ref name="canter-patient">{{Include-USGov|agency=[[National Cancer Institute]]|url=http://www.cancer.gov/cancertopics/pdq/cam/coenzymeQ10/patient|publisher=[[National Cancer Institute]]|title=Coenzyme Q<sub>10</sub>|date=April 2022}}</ref><ref name="pmid26389329">{{cite book|pmid=26389329 |date=2002 |publisher=PDQ Integrative, Alternative, and Complementary Therapies Editorial Board |title=Coenzyme Q10: Health Professional Version |author=((PDQ Integrative, Alternative, and Complementary Therapies Editorial Board)) }}</ref><ref name="White-2014">{{Include-USGov|agency=[[National Cancer Institute]]| vauthors = White J |date= 14 May 2014 |title=PDQ Coenzyme Q<sub>10</sub> |url=http://www.cancer.gov/cancertopics/pdq/cam/coenzymeQ10/HealthProfessional |publisher= [[National Cancer Institute]], [[National Institutes of Health]], [[United States Department of Health and Human Services|U.S. Dept. of Health and Human Services]] |access-date= 29 June 2014}}</ref><ref name="nice.org.uk-2017">{{Cite web |url=https://www.nice.org.uk/advice/es11/resources/mitochondrial-disorders-in-children-coenzyme-q10-pdf-1158110303173 |title=Mitochondrial disorders in children: Co-enzyme Q10 |date=28 March 2017 |website=nice.org.uk |publisher=National Institute for Health and Care Excellence |location=UK |access-date=10 October 2019 |archive-date=10 October 2019 |archive-url=https://web.archive.org/web/20191010120754/https://www.nice.org.uk/advice/es11/resources/mitochondrial-disorders-in-children-coenzyme-q10-pdf-1158110303173 |url-status=live }}</ref> However, it is sold as a [[dietary supplement]] not subject to the same [[Regulation of therapeutic goods|regulations as medicinal drugs]], and is an ingredient in some cosmetics.<ref name="pmid10953455">{{cite journal | vauthors = Hojerová J | title = [Coenzyme Q10--its importance, properties and use in nutrition and cosmetics] | journal = Ceska a Slovenska Farmacie | volume = 49 | issue = 3 | pages = 119–123 | date = May 2000 | pmid = 10953455 }}</ref> The manufacture of CoQ<sub>10</sub> is not regulated, and different batches and brands may vary significantly.<ref name="White-2014"/>

==Research==
A 2014 [[Cochrane review]] found insufficient evidence to make a conclusion about its use for the prevention of heart disease.<ref name="pmid25474484">{{cite journal | vauthors = Flowers N, Hartley L, Todkill D, Stranges S, Rees K | title = Co-enzyme Q10 supplementation for the primary prevention of cardiovascular disease | journal = The Cochrane Database of Systematic Reviews | volume = 2014 | issue = 12 | article-number = CD010405 | date = 4 December 2014 | pmid = 25474484 | pmc = 9759150 | doi = 10.1002/14651858.CD010405.pub2 }}</ref> A 2016 Cochrane review concluded that CoQ<sub>10</sub> had no effect on [[blood pressure]].<ref name="pmid26935713">{{cite journal | vauthors = Ho MJ, Li EC, Wright JM | title = Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | issue = 3 | article-number = CD007435 | date = March 2016 | pmid = 26935713 | pmc = 6486033 | doi = 10.1002/14651858.CD007435.pub3 }}</ref> A 2021 Cochrane review found "no convincing evidence to support or refute" the use of CoQ<sub>10</sub> for the treatment of heart failure.<ref name="pmid35608922">{{cite journal | vauthors = Al Saadi T, Assaf Y, Farwati M, Turkmani K, Al-Mouakeh A, Shebli B, Khoja M, Essali A, Madmani ME | title = Coenzyme Q10 for heart failure | journal = The Cochrane Database of Systematic Reviews | volume = 2021 | issue = 2 | article-number = CD008684 | date = February 2021 | pmid = 35608922 | pmc = 8092430 | doi = 10.1002/14651858.CD008684.pub3 | collaboration = Cochrane Heart Group }}</ref>

A 2017 [[meta-analysis]] of people with heart failure taking 30–100&nbsp;mg/d of CoQ<sub>10</sub> found a 31% lower mortality and increased exercise capacity, with no significant difference in the endpoints of left heart ejection fraction.<ref name="pmid28738783">{{cite journal | vauthors = Lei L, Liu Y | title = Efficacy of CoQ<sub>10</sub> in patients with cardiac failure: a meta-analysis of clinical trials | journal = BMC Cardiovascular Disorders | volume = 17 | issue = 1 | article-number = 196 | date = July 2017 | pmid = 28738783 | pmc = 5525208 | doi = 10.1186/s12872-017-0628-9 | doi-access = free }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref> A 2021 meta-analysis found that CoQ<sub>10</sub> was associated with a 31% lower all-cause mortality in HF patients.<ref>{{Cite journal |last1=Khan |first1=Muhammad Shahzeb |last2=Khan |first2=Fiza |last3=Fonarow |first3=Gregg C. |last4=Sreenivasan |first4=Jayakumar |last5=Greene |first5=Stephen J. |last6=Khan |first6=Safi U. |last7=Usman |first7=Muhammad Shariq |last8=Vaduganathan |first8=Muthiah |last9=Fudim |first9=Marat |last10=Anker |first10=Stefan D. |last11=Butler |first11=Javed |date=June 2021 |title=Dietary interventions and nutritional supplements for heart failure: a systematic appraisal and evidence map |url=https://onlinelibrary.wiley.com/doi/10.1002/ejhf.2278 |journal=European Journal of Heart Failure |language=en |volume=23 |issue=9 |pages=1468–1476 |doi=10.1002/ejhf.2278 |pmid=34173307 |issn=1388-9842 |access-date=10 June 2024 |archive-date=2 January 2023 |archive-url=https://web.archive.org/web/20230102122936/https://onlinelibrary.wiley.com/doi/10.1002/ejhf.2278 |url-status=live }}</ref> In a 2023 meta-analysis of older people, ubiquinone had evidence of a cardiovascular effect, but ubiquinol did not.<ref name="pmid37971634">{{cite journal | vauthors = Fladerer JP, Grollitsch S | title = Comparison of Coenzyme Q10 (Ubiquinone) and Reduced Coenzyme Q10 (Ubiquinol) as Supplement to Prevent Cardiovascular Disease and Reduce Cardiovascular Mortality | journal = Current Cardiology Reports | volume = 25 | issue = 12 | pages = 1759–1767 | date = December 2023 | pmid = 37971634 | pmc = 10811087 | doi = 10.1007/s11886-023-01992-6 | doi-access = free }}</ref>

Although CoQ<sub>10</sub> has been studied as a potential remedy to treat purported muscle-related [[side effect]]s of [[statin]] medications, the results were mixed. Although a 2018 meta-analysis concluded that there was preliminary evidence for oral CoQ<sub>10</sub> reducing statin-associated muscle symptoms, including muscle pain, muscle weakness, muscle cramps, and muscle tiredness,<ref name="pmid30371340">{{cite journal | vauthors = Qu H, Guo M, Chai H, Wang WT, Gao ZY, Shi DZ | title = Effects of Coenzyme Q10 on Statin-Induced Myopathy: An Updated Meta-Analysis of Randomized Controlled Trials | journal = Journal of the American Heart Association | volume = 7 | issue = 19 | article-number = e009835 | date = October 2018 | pmid = 30371340 | pmc = 6404871 | doi = 10.1161/JAHA.118.009835 }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}</ref> 2015<ref name="pmid25440725"/> and 2024<ref name="pmid36852817"/> meta-analysis found that CoQ<sub>10</sub> had no effect on statin myopathy.<ref name="pmid25440725">{{cite journal | vauthors = Banach M, Serban C, Sahebkar A, Ursoniu S, Rysz J, Muntner P, Toth PP, Jones SR, Rizzo M, Glasser SP, Lip GY, Dragan S, Mikhailidis DP | title = Effects of coenzyme Q10 on statin-induced myopathy: a meta-analysis of randomized controlled trials | journal = Mayo Clinic Proceedings | volume = 90 | issue = 1 | pages = 24–34 | date = January 2015 | pmid = 25440725 | doi = 10.1016/j.mayocp.2014.08.021 | type = Systematic Review and Meta-Analysis }}</ref><ref name="pmid36852817"/>

==Pharmacology==
===Absorption===
CoQ<sub>10</sub> in the pure form is a [[crystal]]line powder insoluble in water. Absorption as a pharmacological substance follows the same process as that of lipids; the uptake mechanism appears to be similar to that of [[vitamin E]], another lipid-soluble nutrient.<ref name="Žmitek-2008"/> This process in the human body involves [[secretion]] into the [[small intestine]] of [[pancreatic enzyme]]s and [[bile]], which facilitates [[emulsification]] and [[micelle]] formation required for absorption of [[lipophilic]] substances.<ref name="pmid16551570">{{cite journal | vauthors = Bhagavan HN, Chopra RK | title = Coenzyme Q10: absorption, tissue uptake, metabolism and pharmacokinetics | journal = Free Radical Research | volume = 40 | issue = 5 | pages = 445–453 | date = May 2006 | pmid = 16551570 | doi = 10.1080/10715760600617843 | s2cid = 39001523 }}</ref> Food intake (and the presence of lipids) stimulates bodily biliary excretion of bile acids and greatly enhances absorption of CoQ<sub>10</sub>. Exogenous CoQ<sub>10</sub> is absorbed from the small intestine and is best absorbed if taken with a meal. [[Serum (blood)|Serum]] concentration of CoQ<sub>10</sub> in fed condition is higher than in fasting conditions.<ref name="Bogentoft-1991">{{cite book | vauthors = Bogentoft C, Edlund PO, Olsson B, Widlund L, Westensen K | chapter = Biopharmaceutical aspects of intravenous and oral administration of coenzyme Q10. | title = Biomedical and clinical aspects of coenzyme Q | date = 1991 | volume = 6 | pages = 215–224 }}</ref><ref name="pmid17666877">{{cite journal | vauthors = Ochiai A, Itagaki S, Kurokawa T, Kobayashi M, Hirano T, Iseki K | title = Improvement in intestinal coenzyme q10 absorption by food intake | journal = Yakugaku Zasshi | volume = 127 | issue = 8 | pages = 1251–1254 | date = August 2007 | pmid = 17666877 | doi = 10.1248/yakushi.127.1251 | hdl-access = free | doi-access = free | hdl = 2115/30144 }}{{Verify source|date=November 2010}}</ref>

===Metabolism===
CoQ<sub>10</sub> is metabolized in all tissues, with the metabolites phosphorylated in cells.<ref name=sood/> CoQ<sub>10</sub> is reduced to ubiquinol during or after absorption in the [[small intestine]].<ref name=sood/> It is absorbed by [[chylomicron]]s, and redistributed in the blood within [[lipoprotein]]s.<ref name=sood/> Its elimination occurs via [[bile|biliary]] and [[feces|fecal]] [[excretion]].<ref name=sood/>

===Pharmacokinetics===
Some reports have been published on the [[pharmacokinetics]] of CoQ<sub>10</sub>. The plasma peak can be observed 6–8 hours after oral administration when taken as a pharmacological substance.<ref name=sood/> In some studies, a second plasma peak was observed approximately 24 hours after administration, probably due to enterohepatic recycling and redistribution from the liver to circulation.<ref name="pmid16551570" />

Deuterium-labeled crystalline CoQ<sub>10</sub> was used to investigate pharmacokinetics in humans to determine an elimination half-time of 33 hours.''<ref name="pmid3781673">{{cite journal | vauthors = Tomono Y, Hasegawa J, Seki T, Motegi K, Morishita N | title = Pharmacokinetic study of deuterium-labeled coenzyme Q10 in man | journal = International Journal of Clinical Pharmacology, Therapy, and Toxicology | volume = 24 | issue = 10 | pages = 536–541 | date = October 1986 | pmid = 3781673 }}</ref>''

===Bioavailability===
In contrast to the intake of CoQ<sub>10</sub> as a constituent of food, such as nuts or meat, from which CoQ<sub>10</sub> is normally absorbed, there is a concern about CoQ<sub>10</sub> bioavailability when it is taken as a dietary supplement.<ref name="mantle">{{cite journal|doi=10.3390/antiox9050386|doi-access=free |title=Bioavailability of Coenzyme Q10: An Overview of the Absorption Process and Subsequent Metabolism |date=2020 |journal=Antioxidants |volume=9 |issue=5 |page=386 |pmid=32380795 | vauthors = Mantle D, Dybring A |pmc=7278738 }}</ref><ref>{{cite journal|doi=10.3390/nu11030527|doi-access=free |title=Bioavailability and Sustained Plasma Concentrations of CoQ10 in Healthy Volunteers by a Novel Oral Timed-Release Preparation |date=2019 |journal=Nutrients |volume=11 |issue=3 |page=527 |pmid=30823449 |pmc=6471387 | vauthors = Martucci A, Reurean-Pintilei D, Manole A }}</ref> Bioavailability of CoQ<sub>10</sub> supplements may be reduced due to the lipophilic nature of its molecule and large molecular weight.<ref name=mantle/>

====Reduction of particle size====
[[Nanoparticle]]s have been explored as a delivery system for various drugs, such as improving the oral bioavailability of drugs with poor absorption characteristics.<ref name="pmid9121559">{{cite journal | vauthors = Mathiowitz E, Jacob JS, Jong YS, Carino GP, Chickering DE, Chaturvedi P, Santos CA, Vijayaraghavan K, Montgomery S, Bassett M, Morrell C | title = Biologically erodable microspheres as potential oral drug delivery systems | journal = Nature | volume = 386 | issue = 6623 | pages = 410–414 | date = March 1997 | pmid = 9121559 | doi = 10.1038/386410a0 | s2cid = 4324209 | bibcode = 1997Natur.386..410M }}</ref> However, this has not proved successful with CoQ<sub>10</sub>, although reports have differed widely.<ref name="pmid14621964">{{cite journal | vauthors = Hsu CH, Cui Z, Mumper RJ, Jay M | title = Preparation and characterization of novel coenzyme Q10 nanoparticles engineered from microemulsion precursors | journal = AAPS PharmSciTech | volume = 4 | issue = 3 | article-number = E32 | year = 2003 | pmid = 14621964 | pmc = 2750625 | doi = 10.1208/pt040332 }}{{Verify source|date=November 2010}}</ref><ref name="pmid12564745">{{cite journal | vauthors = Joshi SS, Sawant SV, Shedge A, Halpner AD | title = Comparative bioavailability of two novel coenzyme Q10 preparations in humans | journal = International Journal of Clinical Pharmacology and Therapeutics | volume = 41 | issue = 1 | pages = 42–48 | date = January 2003 | pmid = 12564745 | doi = 10.5414/CPP41042 }}{{Verify source|date=November 2010}}</ref> The use of aqueous [[suspension (chemistry)|suspension]] of finely powdered CoQ<sub>10</sub> in pure water also reveals only a minor effect.<ref name="pmid3718593">{{cite journal | vauthors = Ozawa Y, Mizushima Y, Koyama I, Akimoto M, Yamagata Y, Hayashi H, Murayama H | title = Intestinal absorption enhancement of coenzyme Q10 with a lipid microsphere | journal = Arzneimittel-Forschung | volume = 36 | issue = 4 | pages = 689–690 | date = April 1986 | pmid = 3718593 }}</ref>

====Water-solubility====
Facilitating drug absorption by increasing its solubility in water is a common pharmaceutical strategy and also is successful for CoQ<sub>10</sub>. Various approaches have been developed to achieve this goal, with many of them producing significantly better results over oil-based soft gel capsules despite the many attempts to optimize their composition.<ref name="Žmitek-2008" /> Examples of such approaches are use of the aqueous dispersion of solid CoQ<sub>10</sub> with the [[polymer]] [[tyloxapol]],<ref name="USP619">{{cite patent |inventor = Westesen K, Siekmann B |title=Particles with modified physicochemical properties, their preparation and uses |country=US |number=6197349 |publication-date=2001}}</ref> formulations based on various solubilising agents, such as hydrogenated lecithin,<ref name="US 4483873">{{cite patent| inventor = Ohashi H, Takami T, Koyama N, Kogure Y, Ida K |title=Aqueous solution containing ubidecarenone |country=US |number=4483873 |publication-date=1984}}</ref> and [[complex (chemistry)|complexation]] with [[cyclodextrins]]; among the latter, the complex with [[β-cyclodextrin]] has been found to have highly increased bioavailability<ref name="pmid18645245">{{cite journal | vauthors = Zmitek J, Smidovnik A, Fir M, Prosek M, Zmitek K, Walczak J, Pravst I | title = Relative bioavailability of two forms of a novel water-soluble coenzyme Q10 | journal = Annals of Nutrition & Metabolism | volume = 52 | issue = 4 | pages = 281–287 | year = 2008 | pmid = 18645245 | doi = 10.1159/000129661 | s2cid = 825159 }}</ref><ref name="Kagan-2010">{{cite journal |vauthors = Kagan D, Madhavi D |year=2010 |title=A Study on the Bioavailability of a Novel Sustained-Release Coenzyme Q<sub>10</sub>-β-Cyclodextrin Complex |journal=Integrative Medicine |volume=9 |issue=1}}</ref> and also is used in pharmaceutical and food industries for CoQ<sub>10</sub>-fortification.<ref name="Žmitek-2008" />

==Adverse effects and precautions==
Generally, oral CoQ<sub>10</sub> supplementation is well tolerated.<ref name=lpi/> The most common side effects are gastrointestinal symptoms ([[nausea]], vomiting, [[appetite suppression]], and [[abdominal pain]]), [[rash]]es, and headaches.<ref name="pmid20601617">{{cite journal | vauthors = Wyman M, Leonard M, Morledge T | title = Coenzyme Q10: a therapy for hypertension and statin-induced myalgia? | journal = Cleveland Clinic Journal of Medicine | volume = 77 | issue = 7 | pages = 435–442 | date = July 2010 | pmid = 20601617 | doi = 10.3949/ccjm.77a.09078 | s2cid = 26572524 | doi-access = free }}</ref> Some adverse effects, largely gastrointestinal, are reported with intakes.<ref name=sood/> Doses of 100–300&nbsp;mg per day may induce [[insomnia]] or elevate [[Liver function tests|liver enzymes]].<ref name=sood/> The observed safe level risk assessment method indicated that the evidence of safety is acceptable at intakes up to 1200&nbsp;mg per day.<ref name="pmid16814438">{{cite journal | vauthors = Hathcock JN, Shao A | title = Risk assessment for coenzyme Q10 (Ubiquinone) | journal = Regulatory Toxicology and Pharmacology | volume = 45 | issue = 3 | pages = 282–288 | date = August 2006 | pmid = 16814438 | doi = 10.1016/j.yrtph.2006.05.006 }}</ref>

Caution should be observed in the use of CoQ<sub>10</sub> supplementation in people with bile duct obstruction and during pregnancy or breastfeeding.<ref name=sood/>

==Potential drug interactions ==
CoQ<sub>10</sub> taken as a pharmacological substance has potential to inhibit the effects of [[theophylline]] as well as the [[anticoagulant]] [[warfarin]]; CoQ<sub>10</sub> may interfere with warfarin's actions by interacting with [[cytochrome p450]] enzymes thereby reducing the [[Prothrombin time|INR]], a measure of blood clotting.<ref name="pmid27012265">{{cite journal | vauthors = Sharma A, Fonarow GC, Butler J, Ezekowitz JA, Felker GM | title = Coenzyme Q10 and Heart Failure: A State-of-the-Art Review | journal = Circulation: Heart Failure | volume = 9 | issue = 4 | article-number = e002639 | date = April 2016 | pmid = 27012265 | doi = 10.1161/CIRCHEARTFAILURE.115.002639 | s2cid = 2034503 | doi-access = free }}</ref> The structure of CoQ<sub>10</sub> is similar to that of [[vitamin K]], which competes with and counteracts warfarin's anticoagulation effects. CoQ<sub>10</sub> is not recommended in people taking warfarin due to the increased risk of clotting.<ref name="pmid20601617"/>

==Dietary concentrations==
Detailed reviews on occurrence of CoQ<sub>10</sub> and dietary intake were published in 2010.<ref name="pmid20301015">{{cite journal | vauthors = Pravst I, Zmitek K, Zmitek J | title = Coenzyme Q10 contents in foods and fortification strategies | journal = Critical Reviews in Food Science and Nutrition | volume = 50 | issue = 4 | pages = 269–280 | date = April 2010 | pmid = 20301015 | doi = 10.1080/10408390902773037 | s2cid = 38779392 }}</ref> Besides the endogenous synthesis within organisms, CoQ<sub>10</sub> also is supplied by various foods.<ref name=lpi/> CoQ<sub>10</sub> concentrations in various foods are:<ref name=lpi/>

{| class="wikitable"
|+ CoQ<sub>10</sub> levels in selected foods<ref name="pmid20301015" />
! colspan="2"| Food !! CoQ<sub>10</sub> concentration (mg/kg)
|-
| rowspan="5" | [[Vegetable oil]]s
| [[soybean oil]] || 54–280
|-
| [[olive oil]] || 40–160
|-
| [[grapeseed oil]] || 64–73
|-
| [[sunflower oil]] || 4–15
|-
|[[canola oil]] || 64–73
|-
|rowspan="3"|Beef
| heart || 113
|-
| liver || 39–50
|-
| muscle || 26–40
|-
|rowspan="3" | Pork
| heart || 12–128
|-
| liver || 23–54
|-
| muscle || 14–45
|-
| rowspan="3" | Chicken
| breast || 8–17
|-
|thigh
|24–25
|-
|wing
|11
|-
|rowspan="5" | [[fish as food|Fish]]
| [[sardine]] || 5–64
|-
| [[mackerel]] – red flesh|| 43–67
|-
| [[mackerel]] – white flesh || 11–16
|-
| [[salmon]] || 4–8
|-
| [[tuna]] || 5
|-
|rowspan="6" | [[nut (fruit)|Nut]]s
| [[peanut]] || 27
|-
| [[walnut]] || 19
|-
| [[sesame seed]] || 18–23
|-
| [[pistachio]] || 20
|-
| [[hazelnut]] || 17
|-
| [[almond]] || 5–14
|-
|rowspan="5" | Vegetables
| [[parsley]] || 8–26
|-
| [[broccoli]] || 6–9
|-
| [[cauliflower]] || 2–7
|-
| [[spinach]] || up to 10
|-
| [[Chinese cabbage]] || 2–5
|-
|rowspan="8" | [[Fruit]]
| [[avocado]] || 10
|-
| [[blackcurrant]] || 3
|-
| [[grape]] || 6–7
|-
| [[strawberry]] || 1
|-
| [[Orange (fruit)|orange]] || 1–2
|-
| [[grapefruit]] || 1
|-
| [[apple]] || 1
|-
| [[banana]] || 1
|}

Vegetable oils, meat, and fish are rich in CoQ<sub>10</sub>.<ref name=lpi/> [[Dairy product]]s are much poorer sources of CoQ<sub>10</sub> than animal tissues. Among vegetables, [[broccoli]] and [[cauliflower]] are good sources of CoQ<sub>10</sub>.<ref name=lpi/> Most fruits and berries are poor sources of CoQ<sub>10</sub>, except [[avocado]]s, which have relatively high oil and CoQ<sub>10</sub> content.<ref name="pmid20301015" />

===Intake===
In the developed world, the estimated daily intake of CoQ<sub>10</sub> has been determined at 3–6&nbsp;mg per day, derived primarily from meat.<ref name="pmid20301015" />

South Koreans have an estimated average daily CoQ (Q<sub>9</sub> + Q<sub>10</sub>) intake of 11.6&nbsp;mg/d, derived primarily from [[kimchi]].<ref name="doijfca">{{cite journal|doi=10.1016/j.jfca.2011.03.018 |title=Ubiquinone contents in Korean fermented foods and average daily intakes |date=2011 |journal=Journal of Food Composition and Analysis |volume=24 |issue=8 |pages=1123–1129 | vauthors = Pyo Y, Oh H }}</ref>

===Effect of heat and processing===
Cooking by frying reduces CoQ<sub>10</sub> content by 14–32%.<ref name="pmid9129255">{{cite journal | vauthors = Weber C, Bysted A, Hłlmer G | title = The coenzyme Q10 content of the average Danish diet | journal = International Journal for Vitamin and Nutrition Research | volume = 67 | issue = 2 | pages = 123–129 | year = 1997 | pmid = 9129255 }}</ref>

==History==
In 1950, a small amount of CoQ<sub>10</sub> was isolated from the lining of a horse's gut, a compound initially called ''substance SA'', but later deemed to be quinone found in many animal tissues.<ref name="pmid13622652">{{cite journal | vauthors = Morton RA | title = Ubiquinone | journal = Nature | volume = 182 | issue = 4652 | pages = 1764–1767 | date = December 1958 | pmid = 13622652 | doi = 10.1038/1821764a0 | bibcode = 1958Natur.182.1764M }}</ref> In 1957, the same compound was isolated from [[mitochondria]]l membranes of beef heart, with research showing that it transported electrons within mitochondria. It was called ''Q-275'' as a quinone.<ref name="pmid13622652"/><ref name="pmid13445756">{{cite journal | vauthors = Crane FL, Hatefi Y, Lester RL, Widmer C | title = Isolation of a quinone from beef heart mitochondria | journal = Biochimica et Biophysica Acta | volume = 25 | issue = 1 | pages = 220–221 | date = July 1957 | pmid = 13445756 | doi = 10.1016/0006-3002(57)90457-2 }}</ref> The Q-275/substance SA was later renamed ''ubiquinone'' as it was a ''ubiquitous'' quinone found in all animal tissues.<ref name="pmid13622652"/> In 1958, its full chemical structure was reported.<ref name="pmid13622652"/><ref name="Wolf-1958">{{Cite journal|vauthors=Wolf DE|date=1958|title=Coenzyme Q. I. structure studies on the coenzyme Q group|journal=Journal of the American Chemical Society|volume= 80|issue=17|page=4752|doi=10.1021/ja01550a096|bibcode=1958JAChS..80.4752W |issn=0002-7863}}</ref> Ubiquinone was later called either ''mitoquinone'' or ''coenzyme Q'' due to its participation to the mitochondrial electron transport chain.<ref name="pmid13622652"/> In 1966, a study reported that reduced CoQ<sub>6</sub> was an effective [[antioxidant]] in cells.<ref name="pmid17805631">{{cite journal | vauthors = Mellors A, Tappel AL | title = Quinones and quinols as inhibitors of lipid peroxidation | journal = Lipids | volume = 1 | issue = 4 | pages = 282–284 | date = July 1966 | pmid = 17805631 | doi = 10.1007/BF02531617 | s2cid = 2129339 }}</ref>

== See also ==
* [[Idebenone]] – synthetic analog with reduced oxidant-generating properties
* [[Mitoquinone mesylate]] – synthetic analog with improved mitochondrial permeability

== References ==
{{reflist}}

{{Electron transport chain}}
{{Enzyme cofactors}}
{{Antioxidants}}

{{Authority control}}

{{DISPLAYTITLE:Coenzyme Q<sub>10</sub>}}

[[Category:Antioxidants]]
[[Category:1,4-Benzoquinones]]
[[Category:Cellular respiration]]
[[Category:Coenzymes]]
[[Category:Glycolysis]]
[[Category:Meroterpenoids]]
[[Category:Phenol ethers]]
[[Category:Polyenes]]