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Coenzyme Q10 (CoQ10): Difference between revisions
→Absorption and Metabolism
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==Absorption and Metabolism== | ==Absorption and Metabolism== | ||
===Absorption=== | ===Absorption=== | ||
CoQ<sub>10</sub> is a crystalline powder insoluble in water. Absorption follows the same process as that of lipids; the uptake mechanism appears to be similar to that of vitamin E, another lipid-soluble nutrient. This process in the human body involves secretion into the small intestine of pancreatic enzymes and bile, which facilitates emulsification and micelle formation required for absorption of lipophilic substances. | CoQ<sub>10</sub> is a crystalline powder insoluble in water. Absorption follows the same process as that of lipids; the uptake mechanism appears to be similar to that of vitamin E, another lipid-soluble nutrient. This process in the human body involves secretion into the small intestine of pancreatic enzymes and bile, which facilitates emulsification and micelle formation required for absorption of lipophilic substances.{{pmid|16551570}} 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 concentration of CoQ<sub>10</sub> in fed condition is higher than in fasting conditions.{{pmid|17666877}} | ||
=== Metabolism=== | === Metabolism=== | ||
Data on the metabolism of CoQ<sub>10</sub> in animals and humans are limited.<ref name="Zmitek" /> A study with <sup>14</sup>C-labeled CoQ<sub>10</sub> in rats showed most of the radioactivity in the liver two hours after oral administration when the peak plasma radioactivity was observed, but CoQ<sub>9</sub> (with only 9 isoprenyl units) is the predominant form of coenzyme Q in rats.<ref>{{cite book |first1=H. |last1=Kishi |first2=N. |last2=Kanamori |first3=S. |last3=Nisii |first4=E. |last4=Hiraoka |first5=T. |last5=Okamoto |first6=T. |last6=Kishi |chapter=Metabolism and Exogenous Coenzyme Q<sub>10</sub> in vivo and Bioavailability of Coenzyme Q<sub>10</sub> Preparations in Japan |title=Biomedical and Clinical Aspects of Coenzyme Q |pages=131–142 |publisher=Elsevier |location=Amsterdam |year=1964}}</ref> It appears that CoQ<sub>10</sub> is metabolised in all tissues, while a major route for its elimination is biliary and fecal excretion. After the withdrawal of CoQ<sub>10</sub> supplementation, the levels return to normal within a few days, irrespective of the type of formulation used.<ref name="Ozawa" /> | Data on the metabolism of CoQ<sub>10</sub> in animals and humans are limited.<ref name="Zmitek" /> A study with <sup>14</sup>C-labeled CoQ<sub>10</sub> in rats showed most of the radioactivity in the liver two hours after oral administration when the peak plasma radioactivity was observed, but CoQ<sub>9</sub> (with only 9 isoprenyl units) is the predominant form of coenzyme Q in rats.<ref>{{cite book |first1=H. |last1=Kishi |first2=N. |last2=Kanamori |first3=S. |last3=Nisii |first4=E. |last4=Hiraoka |first5=T. |last5=Okamoto |first6=T. |last6=Kishi |chapter=Metabolism and Exogenous Coenzyme Q<sub>10</sub> in vivo and Bioavailability of Coenzyme Q<sub>10</sub> Preparations in Japan |title=Biomedical and Clinical Aspects of Coenzyme Q |pages=131–142 |publisher=Elsevier |location=Amsterdam |year=1964}}</ref> It appears that CoQ<sub>10</sub> is metabolised in all tissues, while a major route for its elimination is biliary and fecal excretion. After the withdrawal of CoQ<sub>10</sub> supplementation, the levels return to normal within a few days, irrespective of the type of formulation used.<ref name="Ozawa" /> | ||
===Pharmacokinetics=== | ===Pharmacokinetics=== | ||
Some reports have been published on the [[Pharmacokinetics|pharmacokinetics]] of CoQ<sub>10</sub>. The [[Maximum Serum Concentration (Cmax)|plasma peak]] can be observed 2–6 hours after oral administration, depending mainly on the design of the study. In some studies, a second plasma peak also was observed at approximately 24 hours after administration, probably due to both enterohepatic recycling and redistribution from the liver to circulation. | Some reports have been published on the [[Pharmacokinetics|pharmacokinetics]] of CoQ<sub>10</sub>. The [[Maximum Serum Concentration (Cmax)|plasma peak]] can be observed 2–6 hours after oral administration, depending mainly on the design of the study. In some studies, a second plasma peak also was observed at approximately 24 hours after administration, probably due to both enterohepatic recycling and redistribution from the liver to circulation.{{pmid|16551570}} Tomono ''et al''. used deuterium-labeled crystalline CoQ10 to investigate pharmacokinetics in humans and determined an [[Elimination Half-Life|elimination half-time]] of 33 hours.{{pmid|3781673}} | ||
== Biochemical Function == | == Biochemical Function == | ||
CoQ<sub>10</sub> is integral to the electron transport chain on the inner membrane of mitochondria, facilitating the conversion of electrons from food into ATP. Its roles, however, extend beyond energy production. It is essential for uncoupling proteins and controls the permeability transition pore in mitochondria. Additionally, CoQ<sub>10</sub> is involved in extramitochondrial electron transport and affects membrane physicochemical properties. It impacts gene expression, which can alter overall metabolism. The primary alterations in energetic and antioxidant functions are believed to underpin its therapeutic effects {{pmid|35199552}}. | CoQ<sub>10</sub> is integral to the electron transport chain on the inner membrane of mitochondria, facilitating the conversion of electrons from food into ATP. Its roles, however, extend beyond energy production. It is essential for uncoupling proteins and controls the permeability transition pore in mitochondria. Additionally, CoQ<sub>10</sub> is involved in extramitochondrial electron transport and affects membrane physicochemical properties. It impacts gene expression, which can alter overall metabolism. The primary alterations in energetic and antioxidant functions are believed to underpin its therapeutic effects {{pmid|35199552}}. | ||