Frank R. Koniuszy

Coenzyme Q. XXIV. On the significance of coenzyme Q 10 in human tissues

Abstract Several organs and tissues of three humans have been examined for coenzyme Q content. The liver, heart, spleen, kidney, pancreas, and adrenals contain relatively high concentrations of coenzyme Q 10, indicating that studies of the functional relationship of coenzyme Q to diseases involving any of these organs might be important. The thyroid and brain contain quite low levels of Q. The total body content of coenzyme Q 10 appears to be in the range of 0.5–1.5 g., and the intestinal flora may contribute only negligible amounts of Q 10 to body stores. Coenzyme Q 10 would seem to have an important role in human health and disease, because of (a) its presence in essential organs, (b) its direct link to known vitamin derived coenzymes, (c) its coenzymic functions, and (d) an apparent role in oxidative phosphorylation.

Coenzyme Q. IX. Coenzyme Q9 and Q10 content of dietary components

Abstract The results of coenzyme Q analyses of some common dietary ingredients are reported. Corn oil and wheat germ oil contain considerable quantities of coenzyme Q 9 . Smaller amounts of Q 10 were found in butter, green beans, crude soybeans, soybean oil, and isolated soybean protein product. Other materials tested did not contain measurable amounts of coenzyme Q 10 . These data permit the formulation of Q 10 -low or perhaps Q 10 -free diets.

Coenzyme Q. XIII. Isolation, assay and human urinary levels of coenzyme Q10

Pure coenzyme Q10 has been isolated from normal human male urine; a colorimetric assay for determining Q10-levels in urine has been devised and applied to 160 collections representing 63 males and females. The average excretion is ca. 55 μg./24 hr. for males and 22 μg./24 hr. for females. Thirty-five per cent of the 63 individuals excreted < 10 μg./24 hr. on one or more occasions. Whether or not such low levels of Q10 urinary excretion represent tissue deficiency and possible disease state(s) remains for further research.

Determination and levels of coenzyme Q10 in human blood.

Abstract A method devised for the purification of the microgram amounts of coenzyme Q 10 in human blood consists of saponification, solvent extraction, and thin-layer chromatography on silica gel. The concentrate from this chromatography was used in a reaction with ethyl cyanoacetate that gives a blue color caused by ions generated in the reaction. Both of the methoxy groups of coenzyme Q 10 are presumably reactive with the reagent, to give a mixture of two products, with one methoxy group replaced by a moiety of ethyl cyanoacetate. This colorimetric reaction is highly specific, and there is no interference from the tocopherols or members of the vitamin K group. The order of magnitude of coenzyme Q 10 in human blood is about 1 μg/ml as based on the analysis of the bloods from 18 male and 12 female individuals. The range for the 30 individuals was from 0.4 to 1.8 μg/ml. Although these individuals would generally be considered “normal,” it is not known whether everyone was normal as far as the metabolism of coenzyme Q 10 is concerned. The developing knowledge of human blood levels of coenzyme Q 10 and the significance of the presence of this substance in the blood would seem to be of considerable importance in relating coenzyme Q 10 to health and disease.

Urinary excretion of coenzyme Q10 by patients with diabetes mellitus

Abstract The coenzyme Q 10 content of urines of male and female patients having diabetes mellitus and on occasion atherosclerotic heart disease has been determined. One hundred and twenty-six assays of 24-hr, urine collections from a total of 72 patients have shown that the average daily excretion is ca. 71 μg./24 hr. for male patients and 58 μg./24 hr. for female patients. Although coenzyme Q is sparingly soluble in aqueous media, it has been determined that urine has a capacity to contain at least 3–6 times as much coenzyme Q 10 as is normally found. The highest content of coenzyme Q 10 ever observed in a human urine sample is less than the content which has been determined as possible on the basis of solubility measurement. Thus, urine is not essentially saturated with this sparingly soluble coenzyme. It was found that urine does not contain a bound form of coenzyme Q 10 which can be hydrolyzed to free Q 10 by the saponification technique used in the isolation of Q 10 from tissue.