alpha1-Microglobulin as a promising marker of cadmium-induced tubular dysfunction, possibly better than beta2-microglobulin.
The purpose of the present study was to evaluate the validity of alpha1-microglobulin (alpha1-MG) in comparison with popularly used beta2-microglobulin (beta2-MG). A database on 8975 cases of never-smoking adult women was revisited; the data were based on spot urine samples from the women in 10 prefectures all over Japan. The validity of alpha1-MG was examined following essentially the same protocol as beta2-MG was examined in a previous study. Comparisons were made for alpha1-MG as observed (e.g. alpha1-MG(ob)), as corrected for creatinine (CR or cr) (e.g. alpha1-MGcr) and as corrected for a specific gravity (SG or sg) of 1.016 (e.g. alpha1-MGsg). A cut-off value of 5.0 mg alpha1-MG/g cr or l was deduced from 400 microg beta2-MG/g cr taking advantage of the regression equation between alpha1-MG and beta2-MG. The prevalence of alph1-microglobulinuria as corrected for a specific gravity of 1.016 (or alpha1-MGsg-uria in short) was essentially unchanged irrespective of SG, except for in very dense or very thin urine samples. alpha1-MGcr-uria prevalence decreased at higher CR. Comparison of the present observation with previous findings on beta2-MG-uria prevalence showed that the variation in prevalence of MG-uria as a function of urine density was smaller for alpha1-MGsg whereas it was substantially larger for beta2-MGcr, and thus it appeared prudent to consider alpha1-MGsg rather than beta2-MGcr as a marker of tubular dysfunction.
Moriguchi
J
J
Kyoto Industrial Health Association, 67 Nishinokyo-Kitatsuboicho, Nakagyo-ku, Kyoto 604-8472, Japan.
Ezaki
T
T
Tsukahara
T
T
Furuki
K
K
Fukui
Y
Y
Okamoto
S
S
Ukai
H
H
Sakurai
H
H
Ikeda
M
M
D000328:Adult; D015415:Biomarkers / Q000652:urine*; D002104:Cadmium / Q000633:toxicity*; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000209:etiology / Q000473:pathology*; D007684:Kidney Tubules / Q000473:pathology*; D008562:Membrane Glycoproteins / Q000652:urine*; D015842:Serine Proteinase Inhibitors / Q000032:analysis*; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000652:urine*
D015415:Biomarkers; D008562:Membrane Glycoproteins; C109148:SPINT2 protein, human; D015842:Serine Proteinase Inhibitors; D002104:Cadmium; D014360:Trypsin Inhibitor, Kunitz Soybean