Coenzyme Q10 be measured in blood plasma, these measurements reflect dietary intake rather than tissue status. Currently, most clinical centers measure CoQ levels in cultured skin fibroblasts, muscle biopsies, and blood mononuclear cells. Culture fibroblasts can be used also to evaluate the rate of endogenous CoQ biosynthesis, by measuring the uptake of C-labelled "p"-hydroxybenzoate. CoQ shares a biosynthetic pathway with cholesterol. The synthesis of an intermediary precursor of CoQ, mevalonate, is inhibited by some beta blockers, blood pressure-lowering medication, and statins, a class of cholesterol-lowering drugs. Statins can reduce serum levels of CoQ by up to 40%. CoQ is not approved by
Discovery and development of statins because lipophilic statins passively and non-selectively diffuse into both hepatocyte and non-heptatocyte, while the hydrophilic statins rely largely on active transport into hepatocyte to exert their effects. High hepatoselectivity is thought to translate into reduced risk of adverse effects. It has been reported that the organic anion transporting polypeptide (OATP) is important for the hepatic uptake of hydrophilic statins such as rosuvastatin and pravastatin. OATP-C is expressed in liver tissue on the basolateral membrane of hepatocytes and is considered to be a potential contributor for the low IC for rosuvastatin in hepatocytes. Of the marketed statins, cerivastatin was the most