The mitochondrial generation of reactive oxygen species (ROS) plays a central role in many cell signaling pathways, but debate still surrounds its regulation by factors, such as substrate availability, [O2] and metabolic state. Previously, we showed that in isolated mitochondria respiring on succinate, ROS generation was a hyperbolic function of [O2]. In the current study, we used a wide variet...

Fas-Fas ligand (FasL)-dependent pathways exert a suppressive effect on inflammatory responses in immune-privileged organs. FasL expression in hepatic Kupffer cells (KC) has been implicated in hepatic immunoregulation. In this study, modulation of FasL expression of KC by endogenous gut-derived bacterial LPS and the role of reactive oxygen species (ROS) as potential mediators of FasL expression ...

objective: oxidative stress as a consequence of aging can induce infertility in males. in this study, we have investigated the effects of aging on sperm parameters, intra-spermatic water soluble antioxidants, reactive oxygen species (ros), and in vitro blastocyst formation. methods: we chose 5 older nmri male mice (10-12 months) and 5 younger nmri male mice (2-3 months). sperm parameters, ros, ...

Hoffman DL, Salter JD, Brookes PS. Response of mitochondrial reactive oxygen species generation to steady-state oxygen tension: implications for hypoxic cell signaling. Am J Physiol Heart Circ Physiol 292: H101–H108, 2007. First published September 8, 2006; doi:10.1152/ajpheart.00699.2006.—Mitochondria are proposed to play an important role in hypoxic cell signaling. One currently accepted sign...

The innate immune system of the nasal epithelium serves as a first line of defense against invading respiratory viruses including influenza A virus (IAV). Recently, it was verified that interferon (IFN)-related immune responses play a critical role in local antiviral innate immunity. Reactive oxygen species (ROS) generation by exogenous pathogens has also been demonstrated in respiratory epithe...

Chronic exposures to arsenic had been associated with metabolism diseases. Peroxisome proliferator-activated receptor gamma (PPARγ) was found in the liver, regulated metabolism. Here, we found that the expression of PPARγ was decreased, the generation of reactive oxygen species (ROS) and autophagy were increased after treatment with As2O3 in offsprings' livers. Taurine (Tau), a sulfur-containin...

We recently demonstrated that systemic hypoxia during reduced inspired PO(2) produces a rapid increase in leukocyte adherence to rat mesenteric venules. Evidence suggests that the mechanism of this response involves decreased nitric oxide (NO) levels. One possible pathway for NO depletion could involve increased reactive oxygen species (ROS) generation resulting in inactivation of NO. The overa...

Khz is a compound derived from the fusion of Ganoderma lucidum and Polyporus umbellatus mycelia that inhibits the growth of cancer cells. The results of the present study show that Khz induced apoptosis preferentially in transformed cells and had only minimal effects on non-transformed cells. Furthermore, Khz induced apoptosis by increasing the intracellular Ca(2+) concentration ([Ca(2+)](i)) a...

Ischemia is a major cause of brain damage, and patient management is complicated by the paradoxical injury that results from reoxygenation. We have now explored the generation of reactive oxygen species (ROS) in hippocampal and cortical neurons in culture in response to oxygen and glucose deprivation or metabolic inhibition and reoxygenation. Fluorescence microscopy was used to measure the rate...

objective we have previously shown that rose bengal (rb) alone, not as a photosensitiser, could induce apoptotic- and non-apoptotic cell death in different melanoma cell lines. to clarify rb-induced toxicity mechanisms, role of caspases and reactive oxygen specious (ros) were studied in melanoma cells. material and methods human melanoma cell lines, me 4405 and sk-mel-28 were cultured in dmem m...