A photo-activated, protein-based, NO/H2O2 generating system with tumoricidal activity composed of the nitric oxide derivative of apo-metallothionein (thionein-NO) and glucose oxidase
✍ Scribed by Marie Tannous; Natalie Labbe; Robert W. Redmond; Bulent Mutus
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 488 KB
- Volume
- 41
- Category
- Article
- ISSN
- 1011-1344
No coin nor oath required. For personal study only.
✦ Synopsis
The S-nitroso derivalive of apo-metallothionein ( thionein ) was prepared by transnitrosation with S-nitrosoglutathione. The thitmein-NO thus h)rmed has an absorption maximum at 334 rim. Light-induced NO release from thionein-NO was demonstrated by flash photolysis. This system produces peroxynitrite at neutral pH as evidenced by nitrotyrosine formation. The c2~toloxic po!ential of this protein-ha,veal, lightactivated NO/H,O2 generating system was demonstrated by exposing human colon adenocarcinoma cells (SW 948) in culture ~o thionein-NO and glucose exidase in the presence and absence of light. The cell density ot the samples. 72 h subsequent to receiving 1 h of light exposure, decreased by ~ 98cb, relative to controls. In comparison, cell density of the samples that were incubated in the pre~nce of catala,~ and did not meceive light treatment, decreased by only ~ 22% after 72 h.