Peptide Inhibitor of Complement C1 Inhibits the Peroxidase Activity of Hemoglobin and Myoglobin

Figure 5

PIC1 prevents Hb and myoglobin destruction and iron release mediated by NaOCl. (a) RBC lysates (1.25 × 10⁷ cells/ml equivalents), (b) 0.2 mg/ml metHb, and (c) 0.2 mg/ml myoglobin were added to increasing concentrations of PIC1 followed by a 1 : 1,000 dilution of NaOCl. Samples were then incubated for 5 minutes and spectral absorbance readings were recorded from 300 to 550 nm. (d) Free iron (Fe) release from each sample was determined by the ferrozine assay. Data are means of three independent experiments ± SEM.

(a)

(b)

(c)

(d)