Figure 7.

Effects of oral UQ₁₀ supplementation on mitochondrial UQ levels and state 3 respiration rate in the liver. (A) UQ₁₀ administration increases the levels of UQ₁₀ in liver mitochondria. Similar to that shown in Figure 6A, liver mitochondria isolated from Mclk1^liver-KO mice have ∼15% UQ₉ relative to controls (Mclk1^loxP/+) and accumulate DMQ₉. Mitochondrial UQ₁₀ uptake is similar in Mclk1 knockout livers and controls. UQ₁₀ supplementation has no effect on the endogenous content of DMQ₉ and UQ₉. The columns represent the mean ± SEM of quinone peak area on HPLC chromatographs normalized to protein amounts. Mitochondrial UQ concentrations are expressed nmol/mg mitochondrial protein. n = 6 mice per group. (B) Liver mitochondria of UQ₁₀-fed Mclk1^liver-KO mice show a higher state 3 respiration rate (21%–23% more) for both Complex I and II substrates than those of untreated Mclk1^liver-KO mice. Such effect is not seen in control group (Mclk1^loxP/+). Columns represent mean value ± SEM of six mice per group. Statistical evaluation was performed using paired t-test. *P < 0.05.