Coenzyme Q Intake Elevates the Mitochondrial and Tissue Levels of Coenzyme Q and α-Tocopherol in Young Mice

Abstract

The main objective of this study was to resolve the issue of whether the amounts of Coenzyme Q (CoQ), which is endogenously synthesized in cells, can be elevated in tissues and mitochondria of young mice by dietary supplementation with CoQ10. The prevalent view is that the uptake of exogenous CoQ by tissues other than plasma and liver either does not occur or is quite minimal. Mice, 6 mo of age, were fed 0, 148 or 654 mg CoQ10/(kg body x d) in their diets for 11 wk. CoQ10 intake enhanced both CoQ9 and CoQ10 homologues in the plasma, and in homogenates and mitochondria of liver, heart and skeletal muscle. CoQ was elevated in brain mitochondria, but not in the brain homogenate. The uptake of exogenous CoQ was higher in mitochondria of heart and skeletal muscle than those in liver. CoQ10 administration also elevated the alpha-tocopherol concentration in tissue homogenates and their mitochondria, thereby providing an in vivo indication of the "sparing" effect of CoQ on alpha-tocopherol. Results of this study demonstrate that, contrary to the historical view, both total and mitochondrial CoQ concentrations in the heart and skeletal muscle and in the mitochondria of brain of young mice can be augmented by dietary supplementation. Furthermore, CoQ intake enhances the antioxidative potential of tissues by elevating the endogenous amounts of alpha-tocopherol.

Coenzyme Q, oxidative stress and aging

“…Several studies seem to confirm the sparing/regenerative effect of CoQ on α-tocopherol in vivo (reviewed in Sohal, 2004). In young adult mice, CoQ 10 intake effectively augmented the α-tocopherol concentration in tissue homogenates and mitochondria from liver, heart, and skeletal muscle (Kamzalov et al, 2003). A similar effect was observed in homogenates and mitochondria of rats (Fig.…”

“…It was first shown by Matthews et al (1998) that CoQ 10 intake by 12-or 24-month-old rats increased CoQ content in brain mitochondria and had a neuroprotective effect against 3-nitropropionic acid. Subsequently, a series of studies conducted by us (Lass et al, 1999a,b;Lass and Sohal, 2000;Kwong et al, 2002;Kamzalov et al, 2003;Rebrin et al, 2004) demonstrated that CoQ 10 administration via food to young adult mice or rats caused an increase in amounts of both CoQ 9 and CoQ 10 homologues in plasma, and in homogenates and mitochondria of liver, heart and skeletal muscle (Fig. 6).…”

“…These augmentations were equivalent to or greater than those achieved by short-term increases in CoQ dosage. Furthermore, when compared with the relatively hydrophobic CoQ powder, a water-miscible CoQ 10 formulation (Q-Gel from Tishcon) resulted in more consistent augmentation of endogenous CoQ, particularly in brain (see Kwong et al, 2002;Kamzalov et al, 2003versus Lass et al, 1999aSohal et al, 2006). Notwithstanding, it should be noted that the uptake of CoQ and other lipoidal substances is a complex process dependent upon a number of different factors.…”

“…Effect of CoQ 10 intake on CoQ 9 (top panels) and CoQ 10 (bottom) content in mitochondria from different tissues of young adult mice (left) or rats (right). In studies on mice (Kamzalov et al, 2003), CoQ 10 was added to the food yielding daily CoQ intakes of 148 or 654 mg/kg body weight for 11 weeks. Rats were fed an amount equivalent to the low dose (150 mg/kg/d) for 13 weeks prior to tissue collection (Kwong et al, 2002).…”

“…Values are means ± SE for 5-8 mice or 6-7 rats; * p<0.05 when compared with the control group (planned individual comparison within one-way ANOVA). The mouse data are from Kamzalov et al, 2003. Effect of coenzyme Q 10 intake on α-tocopherol concentration in mitochondria from different tissues of young adult mice or rats.…”