The mitochondrial respiratory chain is required for the induction of some yeast hypoxic nuclear genes. Because the respiratory chain produces reactive oxygen species (ROS), which can mediate intracellular signal cascades, we addressed the possibility that ROS are involved in hypoxic gene induction. Recent studies with mammalian cells have produced conflicting results concerning this question. T...

Monocytes and macrophages may either promote or down-regulate inflammatory reactions depending on their state of activation. The effects of glucocorticoids (GCs), the most widely used immunosuppressive drugs, on monocytes are currently not well defined. By analyzing the GC-induced expression pattern in human monocytes by microarray technology, we identified for the first time GC-dependent regul...

OBJECTIVE Oxidative stress has been implicated in cellular senescence and vascular aging. We determined the role and mechanism of the small GTPase rac1 in vascular endothelial cell senescence. METHODS AND RESULTS Adenoviral-mediated expression of the constitutively active allele of rac1 (rac1V12) in human umbilical vein endothelial cells resulted in mitochondrial oxidative stress with inducti...

PURPOSE Induction of oxidative stress has been implicated in UV-induced melanoma. We sought to determine whether the antioxidant N-acetylcysteine (NAC) could be safely administered to protect melanocytic nevi from the oxidative stress resulting from acute UV exposure. EXPERIMENTAL DESIGN Patients at increased risk for melanoma were recruited from a screening clinic. Induction and detection of...

Environmental exposure to the oxidant-producing herbicide, paraquat (PQ) (1,1'-dimethyl-4,4'-bipyridinium dichloride) has long been implicated as a risk factor in Parkinson's disease (PD). PQ-induced oxidative stress has been exploited as a model to screen putative neuroprotective compounds employing Drosophila. In the present study, we investigated the prophylactic efficacy of Bacopa monnieri ...

BACKGROUND AND AIMS Acetaminophen (APAP) or paracetamol is a hepatotoxic drug through mechanisms involving oxidative stress. To know whether mammalian cells possess inducible pathways for antioxidant defense, we have to study the relationship between heme metabolism and oxidative stress. METHODS fasted female Wistar rats received a single injection of APAP (3.3 mmol kg(-1) body weight) and th...