8-hydroxy-2--deoxyguanosine and Glomerulonephritis--IGA

Liver-type fatty acid-binding protein (L-FABP) is a clinical biomarker of tubulointerstitial damage, which plays an essential role in the progression of chronic kidney disease (CKD), including immunoglobin A (IgA) nephropathy. The effect of combination therapy with the angiotensin receptor blocker (ARB) and the angiotensin-converting enzyme inhibitor (ACEI) on CKD has not been elucidated.. Twenty-four normotensive patients with IgA nephropathy were randomly assigned to receive olmesartan 10 mg/day, temocapril 2 mg/day, or combination therapy with both drugs. Urinary levels of L-FABP as well as 8-hydroxydeoxyguanosine (8-OHdG) and protein excretion were measured before and after 3 months of treatment. The chronicity index and activity index were also assessed by histopathologic findings.. Urinary levels of L-FABP and 8-OHdG were higher in patients with IgA nephropathy than in age-matched and sex-matched healthy controls (122.5 +/- 25.5 v 6.4 +/- 3.8 mug/g.creatinine, P < .001; and 22.6 +/- 4.4 v 4.8 +/- 1.4 ng/mg.creatinine, P < .01, respectively). Urinary levels of L-FABP were correlated with those of 8-OHdG (baseline, P = .0001; after 3 months, P = .008) and the severity of proteinuria (baseline, P = .0015; after 3 months, P = .0001). The percent reductions in urinary levels of L-FABP and 8-OHdG, protein excretion, and activity index after 3 months were greater in the combination therapy group, compared with each monotherapy group of olmesartan (P < .05) and temocapril (P < .05).. The data suggest that a combination therapy of ARB plus ACEI has a greater beneficial effect on renal injury compared with monotherapy using ARB or ACEI in normotensive patients with IgA nephropathy.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Blood Pressure; Deoxyguanosine; Double-Blind Method; Drug Therapy, Combination; Fatty Acid-Binding Proteins; Female; Glomerulonephritis, IGA; Heart Rate; Humans; Imidazoles; Male; Proteinuria; Tetrazoles; Thiazepines

Chronic kidney disease patients share clinical and pathological features with the general aging population. Increased oxidative DNA damage, accumulation of cell cycle-arrested cells and decreased Klotho expression are assumed to be age-related factors that are reportedly linked to kidney disease. This study sought to determine the association between these age-related factors and renal damage in patients with IgA nephropathy (IgAN).. We performed a cross-sectional analysis of 71 patients who were diagnosed with IgAN by renal biopsy. Expression of 8-hydroxydeoxyguanosine (8-OHdG, a marker of oxidative DNA damage), p16 (a marker of cell cycle-arrest) and Klotho (an anti-aging protein) were evaluated by immunohistochemical staining of renal biopsy samples. We correlated the changes in expression of these markers with Lee's pathologic grades and the Oxford classification. We also investigated the independent association between these markers and interstitial fibrosis using multiple linear regression analysis.. 8-OHdG and p16 increased but Klotho decreased with progression of pathologic grade. Expression of 8-OHdG and p16 increased with the deterioration of mesangial hypercellularity and segmental glomerulosclerosis. In addition, p16 increased but Klotho decreased with progression of tubular atrophy/interstitial fibrosis. In univariate regression analysis, age, body mass index, systolic blood pressure, urinary protein excretion and expression of 8-OHdG, p16 and Klotho showed significant correlations with interstitial fibrosis. Multivariable regression analyses revealed that aging, increased renal expression of p16 and decreased expression of Klotho were independently correlated with interstitial fibrosis.. The age-related factors might play important roles in the development of IgAN.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Adult; Aging; Cell Cycle Checkpoints; Chronic Disease; Cross-Sectional Studies; Cyclin-Dependent Kinase Inhibitor p16; Deoxyguanosine; Disease Progression; Female; Fibrosis; Glomerulonephritis, IGA; Glucuronidase; Humans; Kidney; Klotho Proteins; Male; Middle Aged; Neoplasm Proteins; Young Adult