Ceruloplasmin oxidase activity as a biomarker of lead exposure.
The most sensitive method used in monitoring the blood lead-level is atomic absorption spectrophotometry. Its limitation due to its high cost has made delta-aminolaevulinic acid dehydratase (delta-ALAD) inhibition more popular. This work demonstrates that ceruloplasmin (Cp), the blue-colored copper containing alpha-2 globulin (alpha(2) globulin) glycoprotein in serum, can serve as a high-potential biomarker for lead exposure. Sephadex G-200 column chromatography demonstrated that lead-intoxicated patient serum transferrin and ceruloplasmin are bound to lead. The ceruloplasmin's oxidase and delta-ALAD activities are reduced when the blood-lead level increases (thresholds of 10.0 and 12.5 mug/100 mL respectively), with a correlation coefficient of -0.8643 and -0.6785 which accurately estimate a blood lead level of 74.7% and 46.0%, respectively. When the blood-lead level was less than 20 mug/100 mL, correlation coefficients of -0.5785 and -0.6963 suggested that Cp may serve as a good biomarker. Other advantages in using Cp in monitoring the blood-lead level were its stability: the enzyme was more stable at -20 degrees C, for more than 2 wk, and its practical and rapid determination procedure.
Leelakunakorn
Warin
W
Department of Pathology, Faculty of Medicine, Mahidol University.
Sriworawit
Rosawan
R
Soontaros
Suganya
S
D000328:Adult; D015415:Biomarkers / Q000378:metabolism*; D002570:Ceruloplasmin / Q000378:metabolism*; D002850:Chromatography, Gel; D005260:Female; D006801:Humans; D007854:Lead / Q000097:blood*; D008297:Male; D000623:Porphobilinogen Synthase / Q000097:blood; D013054:Spectrophotometry, Atomic
D015415:Biomarkers; D007854:Lead; D002570:Ceruloplasmin; D000623:Porphobilinogen Synthase