Abstract
We report data from two related assay systems (isolated enzyme assays and whole blood assays) that C-phycocyanin a biliprotein from Spirulina platensis is a selective inhibitor of cyclooxygenase-2 (COX-2) with a very low IC50 COX-2/IC50 COX-1 ratio (0.04). The extent of inhibition depends on the period of preincubation of phycocyanin with COX-2, but without any effect on the period of preincubation with COX-1. The IC50 value obtained for the inhibition of COX-2 by phycocyanin is much lower (180 nM) as compared to those of celecoxib (255 nM) and rofecoxib (401 nM), the well-known selective COX-2 inhibitors. In the human whole blood assay, phycocyanin very efficiently inhibited COX-2 with an IC50 value of 80 nM. Reduced phycocyanin and phycocyanobilin, the chromophore of phycocyanin are poor inhibitors of COX-2 without COX-2 selectivity. This suggests that apoprotein in phycocyanin plays a key role in the selective inhibition of COX-2. The present study points out that the hepato-protective, anti-inflammatory, and anti-arthritic properties of phycocyanin reported in the literature may be due, in part, to its selective COX-2 inhibitory property, although its ability to efficiently scavenge free radicals and effectively inhibit lipid peroxidation may also be involved. (C) 2000 Academic Press.
Original language | English (US) |
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Pages (from-to) | 599-603 |
Number of pages | 5 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 277 |
Issue number | 3 |
DOIs | |
State | Published - Nov 2 2000 |
Keywords
- Cyclooxygenase-1
- Cyclooxygenase-2
- Inhibition
- Nonsteroidal anti-inflammatory drugs
- Phycocyanin
- Phycocyanobilin
- Reduced phycocyanin
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology