Distribution of antioxidants among blood components and lipoproteins: significance of lipids/CoQ_{10} ratio as a possible marker of increased risk for atherosclerosis
Affiliations: Institute of Biochemistry, Medical School, University of Ancona, Italy | Laboratory of Clinical Chemistry, Lancisi Hospital, Ancona, Italy
Note: [] Correspondence to: Prof. Gian Paolo Littarru, Institute of Biochemistry, University of Ancona, Via Ranieri, 60131 Ancona, Italy. Tel.: +39 071 220 4674; Fax: +39 071 280 1932; E‐mail: littarru@ popcsi.unian.it.
Abstract: Total CoQ_{10} levels were evaluated in whole blood and in plasma obtained from a group of 83 healthy donors. Extraction with light petroleum ether/methanol was more efficient, for whole blood, than the extraction which is often used for plasma and serum, i.e., ethanol hexane. An excellent correlation was present between plasma CoQ_{10} and whole blood CoQ_{10}. CoQ_{10} is mainly associated with plasma rather than with cellular components. Positive, significant correlations were found between the LDL‐chol/CoQ_{10} ratio and the total‐chol/HDL‐chol ratio, which is usually considered a risk factor for atherosclerosis. The proportion of CoQ_{10} carried by LDL was 58 \pm 10%, while the amount carried by HDL was 26 \pm 8%. In VLDL + IDL CoQ_{10} was 16 \pm 8%. The content of CoQ_{10} in single classes of lipoproteins is strictly correlated with CoQ_{10} plasma concentration. In a parallel study conducted on a population of diabetic patients (one IDDM group and one NIDDM) CoQ_{10} plasma levels were generally higher compared to the control group, also when normalised to total cholesterol. In particular the LDL fraction showed a CoQ_{10}/chol ratio higher in NIDDM but not in IDDM patients, compared to controls. The CoQ_{10}/triglycerides ratio was lower in NIDDM respect to controls and even lower in IDDM patients.
Journal: Biofactors, vol. 9, no. 2-4, pp. 231-240, 1999
