39 α-lipoic selleck products acid (α-LA) is also found naturally in mitochondria and acts as a critical coenzyme for the mitochondria enzymes pyruvate dehydrogenase and α—ketoglutarate dehydrogenase.40 Its reduced form, dihydrolipoic acid (DHLA), and other metabolites have strong antioxidant effects as ROS scavengers and act as chelators of transition metals.41 In a PBOO study, CoQ10 plus α-LA treatment significantly
increased bladder contractility in vitro, decreased bladder wall protein carbonylation and nitration, increased mitochondrial function, prevented intramural nerve degeneration and diminished detrusor smooth muscle hypertrophy in rabbit bladder.26 Specifically, bladder voiding contraction can be separated into two phases: an initial peak phase and a second tonic phase.42 The initial peak response p38 MAP Kinase pathway was supported energetically by extant cellular ATP stores, whereas the tonic phase required active mitochondrial oxidation of substrates to generate energy. Ability of the bladder to sustain contraction is directly related to the availability of energy produced by mitochondrial electron transport and oxidative phosphorylation.42 Decompensation of bladder from extended obstruction may
be mediated by breakdown of mitochondrial function. Both CoQ10 and α-LA are essential mitochondrial components in respiratory chain and pyruvate-dehydrogenase complex. Combination therapy may target several common pathways in mitochondrial dysfunctions. Following 4 weeks PBOO, both choline acetyl-transferase activity (an indicator of cholinergic function) and neurofilament amounts decreased significantly and diminished further after 7 weeks of obstruction. PBOO also significantly increased both protein nitration and carbonylation following obstruction, especially after 7 weeks obstruction. CoQ10 and α-LA are both strong antioxidant reagents in nature. Treatment with CoQ10 plus α-LA significantly attenuated protein carbonylation Mannose-binding protein-associated serine protease and nitration, indicating that these medications
may work through an antioxidative effect. The antioxidative function of CoQ10 is likely to occur by providing hydrogen equivalents to reduce peroxyl and/or generation of alkoxylradicals.39α-LA has also been proven to reduce lipid peroxidation by enhancing the activity of glutathione peroxidase and SOD, which improves the efficiency of the endogenous antioxidant systems.43 A combination of these two strong antioxidants thus prevents free radical induced tissue damages subjected to PBOO. Ischemia/reperfusion injury is also involved in bladder overdistention injury. It has been known for a long time that bladder overdistention reduces blood perfusion of the bladder.44 Blood flow is resumed following emptying and decompressing the urinary bladder. Reperfusion of the overdistended and ischemic urinary bladder might induce reperfusion injury. In a rabbit overdistention model, Lin et al.