DNA adducts are produced both exogenously and endogenously via exposure to various DNA-damaging agents. Two lipid peroxidation (LPO) products, 4-oxo-2(E)-nonenal (4-ONE) and 4-oxo-2(E)-hexenal (4-OHE), induce substituted etheno-DNA adducts in cells and chemically treated animals, but the adduct levels in humans have never been reported. It is important to investigate the occurrence of 4-ONE- and 4-OHE-derived DNA adducts in humans to further understand their potential impact on human health. In this study, we conducted DNA adductome analysis of several human specimens of pulmonary DNA as well as various LPO-induced DNA adducts in 68 human autopsy tissues, including colon, heart, kidney, liver, lung, pancreas, small intestine, and spleen, by liquid chromatography tandem mass spectrometry. In the adductome analysis, DNA adducts derived from 4-ONE and 4-OHE, namely, heptanone-etheno-2'-deoxycytidine (HεdC), heptanone-etheno-2'-deoxyadenosine (HεdA), and butanone-etheno-2'-deoxycytidine (BεdC), were identified as major adducts in one human pulmonary DNA. Quantitative analysis revealed 4-ONE-derived HεdC, HεdA, and heptanone-etheno-2'-deoxyguanosine (HεdG) to be ubiquitous in various human tissues at median values of 10, 15, and 8.6 adducts per 10(8) bases, respectively. More importantly, an extremely high level (more than 100 per 10(8) bases) of these DNA adducts was observed in several cases. The level of 4-OHE-derived BεdC was highly correlated with that of HεdC (R(2) = 0.94), although BεdC was present at about a 7-fold lower concentration than HεdC. These results suggest that 4-ONE- and 4-OHE-derived DNA adducts are likely to be significant DNA adducts in human tissues, with potential for deleterious effects on human health.

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In proliferative glomerulonephritis, both macrophages and mesangial cells generate reactive oxygen species (ROS), contributing to the development of glomerular injury. We have attempted to determine which cell produces ROS during anti-Thy1 nephritis (ATN) in rats. The generation of ROS was studied using luminol amplified chemiluminescence (GCL) on isolated glomeruli. Immunohistochemical studies used avidin-biotin complex (ABC) to label macrophages and mesangial cells. Immediately after ATN induction, mesangiolysis and infiltration with ED-1 positive cells (referred to as macrophage) was noted with a peak at day 1. After day 4, mesangial proliferation appeared with a decrease of the ED-1 positive cells and a prominent increase of PCNA positive cells (regarded as mesangial cells). In the early phase of ATN, GCL, reflecting ROS generation, increased along with the appearance of ED-1 positive cells. GCL subsequently decreased as mesangial cells increased. This suggested that macrophage were the principal participants in ROS generation in the early phase of ATN although mesangial cells cannot be completely disregarded in the generation of ROS and development of glomerular injury.

A high-fat diet aggravates tubulointerstitial but not glomerular density lipoprotein (LDL) [1]. Although many studies lesions in obese Zucker rats.have evaluated the effects of dietary fat on glomerular Background. Despite a large body of evidence that manipulesions, limited information is available regarding its eflation of dietary fat alters glomerular lesions, reports regarding fects on tubulointerstitial lesions. To examine whether a the effects of dietary fat on tubulointerstitial lesions are limited. high-fat diet aggravates glomerular and tubulointerstitialObese Zucker rats (OZR) spontaneously develop glomerular and tubulointerstitial lesions in association with hyperlipidlesions, we administered a high (20%)-or low (1%)-fat emia. We sought to elucidate the effects of dietary fat on diet to OZR and lean Zucker rats (LZR) for 30 weeks. glomerular and tubulointerstitial lesions in OZR versus leanIn this study, the high-fat diet aggravated tubulointer-Zucker rats (LZR) and to assess the involvement of macrostitial but not glomerular injury in OZR, whereas the phages in the development of these lesions.Methods. We fed LZR and OZR either a low-(1%) or opposite occurred in LZR. We also evaluated whether high-fat (20%) diet. After 30 weeks of the specified diet, the macrophages are involved in the development of dietary creatinine clearance (C Cr ) and renal histology as well as plasma fat-induced tubulointerstitial and glomerular lesions in lipid concentrations were examined. For morphological evaluathese rats.tion, glomerular sclerosis (GSI) and tubulointerstitial indices (TII) were each determined by a point-counting method. Infiltrating macrophages were stained immunohistochemically us- METHODSing an avidin-biotin complex technique. Results. The high-fat diet increased the plasma low-densityFive-week-old male LZR and OZR were purchased lipoprotein concentration in OZR. Both low-and high-fat OZR from Charles River Laboratories (Kingston, NY, USA).groups had higher GSI and TII than LZR receiving either diet.Rats had free access to food. LZR and OZR were eachThe high-fat diet aggravated TII but not GSI or C Cr in OZR;divided into two groups according to dietary fat content:conversely, high fat intake worsened GSI and C Cr but not TII in LZR. Tubulointerstitial macrophages were most prominent low-fat LZR (N ϭ 9), high-fat LZR (N ϭ 7), low-fat in the high-fat OZR group, followed by the low-fat OZR group.OZR (N ϭ 6), and high-fat OZR (N ϭ 8). Low-fat rats Glomerular macrophages were similar in number in all groups.were given a daily diet with 1% fat (corn oil, 0.5%; lard,Conclusions. The manipulation of dietary fat has diverse 0.5%). The high-fat diet included 20% fat (corn oil, 10%;effects on the kidney. A high-fat diet aggravated macrophagemediated tubulointerstitial lesions in OZR, whereas in LZR, lard, 10%). The rats' body weight was measured every the diet induced glomerulosclerosis.