Increase of plasma membrane oxidoreductase activity is not correlated with the production of extracellular Superoxide radicals in human Namalwa cells

Abstract

We have considered the regulatory interrelationship of the plasma membrane oxidoreductase (PMOR) system and the mitochondrial respiratory capacity of human Namalwa (lymphoblastoid) cells. To this end, we made use of mitchondrially respiratory competent (ρ{variant}+) cells and ρ{variant}0 cells, which lack mitochondrial DNA (mtDNA) and consequently mitochondrial respiratory activity. NADH-fer-ricyanide reductase activity of the PMOR system is increased 3-fold in ρ{variant}0 Namalwa cells compared to ρ{variant}+ cells. It is also shown for the first time that addition of coenzyme Q10 and coenzyme Q10-ana-logues, which can rescue ρ{variant}0 Namalwa cells in the absence of pyravate, gives rise ..