PubMed · 16122473
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
Kirk Kanter. 2005. Invited commentary.. https://doi.org/10.1016/j.athoracsur.2005.05.098
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
Reactive oxygen species are associated with various diseases including cardiovascular diseases, neurological disorders, and pulmonary diseases. Extracellular superoxide dismutase (ECSOD) is an antioxidant enzyme secreted by cells to prevent overproduction of reactive oxygen species. We expressed an ECSOD gene isolated from a human aortic smooth muscle cDNA library in the methylotrophic yeast Pichia pastoris. A synthetic secretion cassette was constructed with the inducible promoter of the alcohol oxidase 1 gene (AOX1) and the yeast alpha-mating factor signal peptide. As much as 25% of the total protein was ECSOD in some transformants grown under inducing conditions. After 36 h of methanol induction, ECSOD was exported into the culture medium at a concentration of approximately 440 mg/L with an antioxidative activity of 760 +/- 20 U/mg ECSOD. Transformed yeast cells were more resistant to heat shock and H(2)O(2) oxidative stress, indicating that the human ECSOD expressed by P. pastoris had multiple biological functions. Our data suggest that the methylotrophic yeast inducible system is suitable for large-scale production of enzymatically active human ECSOD.
Matrix metalloproteinase-9 (MMP-9) plays a major role in the pathogenesis of atherosclerosis and restenosis by regulating both migration and proliferation of vascular smooth muscle cells (VSMC) after an arterial injury. In this study, we examined the inhibitory effect of three major flavonoids in Scutellariae Radix, baicalin, baicalein, and wogonin, on TNF-alpha-induced MMP-9 expression in human aortic smooth muscle cells (HASMC). Wogonin, but not baicalin and baicalein, significantly and selectively suppressed TNF-alpha-induced MMP-9 expression in HASMC. Reporter gene, electrophoretic mobility shift, and Western blotting assays showed that wogonin inhibits MMP-9 gene transcriptional activity by blocking the activation of NF-kappaB via MAPK signaling pathways. Moreover, the Matrigel migration assay showed that wogonin reduced TNF-alpha-induced HASMC migration. These results suggest that wogonin effectively suppresses TNF-alpha-induced HASMC migration through the selective inhibition of MMP-9 expression and represents a potential agent for the prevention of vascular disorders related to the migration of VSMC.