Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Exposure to hyperoxia causes alveolar macrophage (AM) injury. The present study investigates the roles of intracellular antioxidant enzymes and of glutathione in the protection of AMs against hyperoxia in a biphasic cell culture system in aerobiosis. The effect of normoxia or hyperoxia on the integrity of AMs was related to indices of cell injury (ATP cell content and lactate dehydrogenase release into culture medium) and cell mass (protein content of AMs). Antioxidant activities were measured in guinea-pig AMs exposed to 95% O2 or to normoxia (control cells) for 3 days. A 3-day AM culture in normoxia showed a significant decrease in protein and catalase, whereas ATP cell content, superoxide dismutase (SOD) (both Cu,Zn-SOD and Mn-SOD) and glutathione peroxidase (GPx) activities significantly increased. The content of reduced glutathione (GSH) did not change. Using the ATP content in AMs expressed as a cell injury index (CII), AM injury increased with increasing O2 exposure time (1 day: 13 +/- 4.4%; 2 days: 34 +/- 3.8%; 3 days: 40 +/- 4.1%; 4 days: 55 +/- 7.3%; 6 days: 87.5 +/- 5.4%). Exposure to 95% O2 for 3 days was associated with a significant decrease in ATP cell content, protein, catalase and GSH to the total glutathione ratio, whereas SOD, GSH and total glutathione did not change significantly. The GPx activities increased significantly. There was no significant correlation between the AM CII and SOD or GPx content. In contrast, a significant correlation was observed between hyperoxia-induced AM CII and catalase content (r = 0.71) and glutathione content (r = 0.71).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Relationship between oxygen-induced alveolar macrophage injury and cell antioxidant defence. 774 27

Haemophilus influenzae type b, a causative agent of bacterial sepsis and meningitis in young children, contains a single superoxide dismutase (SOD), a cytoplasmic MnSOD. To study the role of this enzyme, a chromosomal sodA::lacZ mutant (M-2) was constructed. M-2 had an increased sensitivity towards oxygen and the redox-active agent paraquat. A 3.4-fold increase in sodA-lacZ expression was found in M-2 grown with oxygen supply rates between 3 and 36 mmol of O2/liter/h. In similar experiments with the wild type, assaying SodA activity, a 3.1-fold increase was found. Both the wild type and M-2 grew best at the lowest oxygen supply rate tested, consistent with the notion that H. influenzae prefers a more anaerobic environment. In the infant rat model of infection, the ability of M-2 to colonize the nasopharynx was found to be impaired, but its ability to cause invasive disease was unaffected. This suggests that after invasion, the growth disadvantage imposed by a SodA- phenotype is not limiting.
 ...
PMID:Role of bacterial Mn-cofactored superoxide dismutase in oxidative stress responses, nasopharyngeal colonization, and sustained bacteremia caused by Haemophilus influenzae type b. 919 39