Coenzyme Q (CoQ) Flashcards
CoQ10 plays a role in cellular __ and is an important __
CoQ10 plays a role in cellular bioenergetics and is an important antioxidant
absorption of CoQ10 is slow and limited b/c of its __ and __
absorption of CoQ10 is slow and limited b/c of its hydrophobicity and large molecular weight
CoQ10 is taken up by all tissues including __ and __ __
CoQ10 is taken up by all tissues including heart and brain mitochondria
CoQ is a __ occurring compound with properties similar to __
CoQ is a naturally occurring compound with properties similar to vitamins
CoQ is aka
ubiquinone
bc it is ubiquitous
CoQ is similar to vitamin _
CoQ is similar to vitamin K
why is CoQ10 not considered a vitamin
bc it is synthesized in the body
CoQ10 is a cofactor in the __ and is therfore essential for production of __
CoQ10 is a cofactor in the mitochondrial ETC and is therfore essential for production of ATP
In ETC, CoQ10 is a __ agent that shuttles __ and __ in mitochondria
In ETC, CoQ10 is a redox agent that shuttles electrons and protons in mitochondria
CoQ10 reduced form is called
hydroquinone
hydroquinone (reduced CoQ10) helps to recycle and regenerate other __
hydroquinone (reduced CoQ10) helps to recycle and regenerate other antioxidants
CoQ10 supplements appear to help __ and __
CoQ10 supplements appear to help CVD and neurodegenerative diseases
CoQ10 is lipophilic/lipophobic
CoQ10 is lipophilic
absorption of CoQ10 is enhanced by the presence of __
absorption of CoQ10 is enhanced by the presence of lipids
gastric digestion of food matrix is important for __
gastric digestion of food matrix is important for CoQ10 digestion
after being absorbed, CoQ10 is packed into __ and transported via __ to circulation
after being absorbed, CoQ10 is packed into chylomicrons and transported via lymphatics to circulation
Does HDL contain any CoQ10?
a bit
absorption of CoQ10 once in enterocyte
- CoQ10 1st incorporated into chylomicrons following absorption and transported via the
lymphatics to the circulation - CoQ10 is reduced to ubiquinol either during or following absorption in the intestine
- Ubiquinol appears as part of mesenteric triacylglycerol-rich lipoproteins
- Lipoprotien lipase converts mesenteric triacylglycerol-rich lipoproteins into chylomicron
remnants in circulation - Chylomicron remnants are taken up rapidly by the liver where CoQ10 is repackaged
mostly into VLDL/LDL particles and rereleased into circulation
plasma CoQ10 levels depend on __
plasma CoQ10 levels depend on plasma lipoproteins
95% of CoQ10 in circulation exists as __ (__ form)
95% of CoQ10 in circulation exists as ubiquinol (reduced form)
CoQ10 is found in __ tissues
CoQ10 is found in all tissues
CoQ10 has higher concentrations in tissues with __ such as __, __, __, and __
CoQ10 has higher concentrations in tissues with higher energy requirements such as heart, liver, kidney, and muscle
CoQ10 also has higher concentrations in tissues with high __ content, such as __
CoQ10 also has higher concentrations in tissues with high lipid content, such as membranes
high conc of CoQ10 in which part of mitochondria?
inner membrane
CoQ10 has highest conc in (2)
- tissues with high energy requirements
- parts of cell with high lipid content
most CoQ10 is in the __ form except in the brain and lungs where it is in its __ form
most CoQ10 is in the reduced form except in the brain and lungs where it is in its oxidized form
2 reduced forms of CoQ10
hydroquinone
ubiquinol
RBC have __ CoQ10 bc
RBC have little CoQ10 bc they lack mitochondria
CoQ10 is in most reduced state in (3) tissues
plasma
intestine
liver
CoQ10 is synthesized de novo in __ tissues, so there is no need for __ supply
CoQ10 is synthesized de novo in all tissues, so there is no need for exogenous supply
intestinal absorption of CoQ10 is __
intestinal absorption of CoQ10 is limited
metabolism of CoQ10: what do we know?
not much
metabolism studies with radiolabeled CoQ10 and CoQ7 indicate that it is stored in __ and reabsorbed with __
metabolism studies with radiolabeled CoQ10 and CoQ7 indicate that it is stored in liver and reabsorbed with bile
in rats, exogenous CoQ10 can be converted to __
in rats, exogenous CoQ10 can be converted to CoQ9
in a rat study with labeled CoQ10, all organs that took up labeled CoQ10 also contained __
in a rat study with labeled CoQ10, all organs that took up labeled CoQ10 also contained water soluble metabolites
most CoQ10 is excreted by __, but some in __
most CoQ10 is excreted by kidneys, but some in feces
CoQ10 is metabolized in __ tissues, the metabolites are __ in the cells, transported in the __ to the __, and excreted into the __
CoQ10 is metabolized in all tissues, the metabolites are phosphorylated in the cells, transported in the blood to the kidney, and excreted into the kidney
main way to assess CoQ10 status
plasma or serum concentration from FASTED samples
plasma CoQ10 levels reflect (2)
- amount of absorbed CoQ10
- Approximate tissue CoQ10 content
how much does dietary CoQ10 contribute?
not much at all
CoQ10 is used to treat __, __, and __ disease bc of its role in __ and __
CoQ10 is used to treat cardiovascular, mitochondrial, and neurologic disease bc of its role in mitochondrial function and cellular bioenergetics
CoQ10 is present in __ tissues, especially those with __
takeaway
CoQ10 is present in ALL tissues, especially those with high energy requirements
__ contain high conc of CoQ10
takeaway
mitochondria contain high conc of CoQ10
CoQ10 is an important __ __
takeaway
CoQ10 is an important lipophilic antioxidant
CoQ10 is synthesized de novo by __
takeaway
CoQ10 is synthesized de novo by eevry cell in the body
CoQ10 is very __ and __, so absorption is slow and limited
CoQ10 is very hydrophobic and large, so absorption is slow and limited
