Background. Coenzyme Q10 belongs to important antioxidants and it has a key role in the synthesis of adenosinephosphate. Its beneficial effect was proved in several diseases, e.g. in mitochondrial encephalopathy, mitochondrial myopathy, mitochondrial cardiomyopathy. Material and Methods. All 15 patients of the studied group (5 with tubulopathy and 10 with chronic tubulointersticial nephritis) received antioxidative therapy for three months (E vitamin, C vitamin, riboflavin) and for the last two months coenzyme Q10 was added. Renal functions, spectrum of lipids, parameters of lipid peroxidation (malondialdehyde), levels of a-tocopherol, b-carotene, coenzyme Q10. Results. Before the substitutive antioxidative treatment, coenzyme Q10 levels reached in blood 0.11 ± 0.03 mmol/l and 0.15 ± 0.04 mmol/l in plasma. These values were well below the reference range (rr) is 0.4 ± 1.0 mmol/l). After the substitution coenzyme Q10 levels significantly increased (p<0.001) to the values of 1.66 ± 0.16 mmol/l in blood and to 1.78 ± 0.27 mmol/l in plasma. Plasma levels of b-carotene increased from the markedly subnormal values 0.25 ± 0.07 mmol/l (rr>0.08 mmol/l) to 0.56 ± 0.02 mmol/l (no statistical difference). Plasma levels of a-tocopherol remained within the reference range 32.15 ± 4.73 mmol/l (rr 15-30 mmol/l) and they increased up to the plasma level of 44.83 ± 5.82 mmol/l during the period of testing. Malondialdehyde levels did not significantly change within the testing period. No changes in renal function and parameters of lipid metabolism were described. Patients well tolerated the treatment and no adverse effects were seen during the period of observation. Conclusions. Our results ascertained that levels of antioxidant CoQ10 were lower in patients with nephropathy who underwent conservative treatment with peroral substation. Such devicit can be amended by CoQ10 administration, which could be therefore taken as complementary treatment of nefrology.

        Key words: coenzyme Q10, antioxidants, renal diseases, lipid peroxidation.