Increased mRNA expression of metalloproteinase-9 in peripheral blood monocytes from patients with immunoglobulin A nephropathy.
We examined metalloproteinase (MMP)-1, -2, -3, and -9 mRNA expression by peripheral blood monocytes from 50 patients with immunoglobulin A (IgA) nephropathy, 20 with membranous nephropathy, 10 with minimal-change nephrotic syndrome, five with focal glomerulosclerosis, 30 with non-IgA proliferative glomerulonephritis, and 40 healthy normal controls who were comparable with regard to age and sex. Monocytes from patients with IgA nephropathy expressed a higher level of MMP-9 mRNA than those from patients with other forms of glomerulonephritis or from healthy controls (MMP-9 to glyceraldehyde-3-phosphate dehydrogenase ratio: IgA nephropathy, 1.68 +/- 0.24; membranous nephropathy, 0.22 +/- 0.08; minimal-change nephrotic syndrome, 0.24 +/- 0.06; focal glomerulosclerosis, 0.32 +/- 0.08; non-IgA proliferative glomerulonephritis, 0.30 +/- 0.12; and healthy controls, 0.16 +/- 0.04). When the biopsy specimens were classified into four grades according to the severity of glomerular and interstitial pathology, highly significant differences were observed among MMP-9 mRNA levels in monocytes from all four groups of patients with IgA nephropathy (grade I, 0.44 +/- 0.09; grade II, 1.06 +/- 0.26; grade III, 2.22 +/- 0.68; grade IV, 2.86 +/- 0.88). In addition, MMP-9 mRNA levels from patients with IgA nephropathy correlated with urinary protein excretion (P < 0.001). However, we detected minimal mRNA expression of MMP-1, -2, and -3 by peripheral blood monocytes from patients with IgA nephropathy or other forms of glomerulonephritis and from normal healthy controls. Our results suggest that increased MMP-9 mRNA expression in circulating monocytes may contribute to the progression of IgA nephropathy.
Koide
H
H
Division of Nephrology, Department of Medicine, Juntendo University School of Medicine, Koto Hospital, Tokyo, Japan.
Nakamura
T
T
Ebihara
I
I
Tomino
Y
Y
D000328:Adult; D001706:Biopsy; D015152:Blotting, Northern; D016022:Case-Control Studies; D005260:Female; D015870:Gene Expression; D005921:Glomerulonephritis / Q000201:enzymology / Q000473:pathology; D005922:Glomerulonephritis, IGA / Q000201:enzymology* / Q000473:pathology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000096:biosynthesis / Q000097:blood; D006801:Humans; D007678:Kidney Glomerulus / Q000473:pathology; D007963:Leukocytes, Mononuclear / Q000201:enzymology*; D008297:Male; D008666:Metalloendopeptidases / Q000096:biosynthesis* / Q000097:blood; D009402:Nephrosis, Lipoid / Q000201:enzymology / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics
D012333:RNA, Messenger; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D008666:Metalloendopeptidases