In this study, by using highly purified rat liver peroxisomes, we provide evidence from analytical cell fractionation, Western blot, and immunocytochemical analysis that Cu-Zn superoxide dismutase is present in animal peroxisomes. Treatment with ciprofibrate, a peroxisome proliferator, increased the peroxisomal superoxide dismutase activity by 3-fold with no effect on mitochondrial activity but...

The intracellular localization of Cu,Zn superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) has been examined by immunofluorescence using four monoclonal anti-Cu,Zn superoxide dismutase antibodies raised against a recombinant human Cu,Zn superoxide dismutase derivative produced and purified from Escherichia coli. Colocalization with catalase, a peroxisomal matrix enzyme, wa...

The role of superoxide anion- and myeloperoxidase-dependent reactions in the light emission by phagocytosing polymorphonuclear leukocytes has been investigated using leukocytes that lack myeloperoxidase, inhibitors (azide, superoxide dismutase), and model systems. Our earlier finding that oxygen consumption, glucose C-1 oxidation, and formate oxidation are greater in polymorphonuclear leukocyte...

PURPOSE Retinal ganglion cells (RGCs) undergo apoptosis after axonal injury. The time course of cell death is variable and depends in part on the degree of injury sustained. Decreasing reactive oxygen species (ROS) levels or shifting the redox state to reduction promotes the survival of RGCs in tissue culture after axotomy. It was hypothesized that a specific ROS, superoxide anion, acts as an i...

Superoxide is the proximal reactive oxygen species (ROS) produced by the mitochondrial respiratory chain and plays a major role in pathological oxidative stress and redox signaling. While there are tools to detect or decrease mitochondrial superoxide, none can rapidly and specifically increase superoxide production within the mitochondrial matrix. This lack impedes progress, making it challengi...

Erythrocyte superoxide dismutase activities were measured in 45 subjects, 15 each of beta 0-thalassaemia/haemoglobin (Hb) E disease, Hb H disease, and normal. The erythrocyte superoxide dismutase activities were significantly higher in the patients with beta 0-thalassaemia/Hb E and Hb H diseases than in the normal subjects. The increase of erythrocyte superoxide dismutase activities is most lik...

Superoxide released from mitochondria forms reactive oxygen species that can cause severe oxidative damage and have been associated with aging- and disuse-induced muscle dysfunction. Superoxide is released to both the exterior and the matrix of mitochondria, where oxidative damage is not necessarily the same. This complicates determining the role of mitochondrial superoxide in eliciting oxidati...

The structure-activity relationship of flavonoids as inhibitors of xanthine oxidase and as scavengers of the superoxide radical, produced by the action of the enzyme xanthine oxidase, was investigated. The hydroxyl groups at C-5 and C-7 and the double bond between C-2 and C-3 were essential for a high inhibitory activity on xanthine oxidase. Flavones showed slightly higher inhibitory activity t...