Reaction of endogenous Coenzyme Q₁₀ with nitrogen monoxide and its metabolite nitrogen dioxide

Figures & data

Scheme 1. Interconversion between CoQ₁₀H₂ and CoQ₁₀.

Figure 1. EPR signals recorded on liposomes suspension containing CoQ₁₀: (a) untreated; (b) treated with ^•NO₂ or ^•NO/^•NO₂; (c) treated with ^•NO₂ or ^•NO/^•NO₂ and extracted with CHCl₃.

Scheme 2. Sequence of reactions responsible for nitroxide 6 formation.

Figure 2. EPR signals recorded on mitochondria suspension: (a) untreated; (b) treated with ^•NO₂ or ^•NO/^•NO₂; (c) treated with ^•NO₂ or ^•NO/^•NO₂, lysed with Triton X-100 and extracted with CHCl₃.

Figure 3. EPR signal recorded on human plasma treated with ^•NO/^•NO₂ after addition of CHCl₃: (a) plasma sample and (b) plasma sample collected after CoQ₁₀ administration.

Figure 4. Kinetic of the reaction CoQ₁₀ + ^•NO₂. Linear fit was done for the 400 first seconds leading to a k = 7.28 × 10⁻⁸M s⁻¹.