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Notes: The purpose of the present study was to evaluate the role of angiotensinogen (AGT) gene polymorphisms in the progression of IgA nephropathy (IgAN). The association of the haplotypes defined by A-20C and M235T, which correspond to G-6 A polymorphisms, with the severity of glomerular or interstitial lesions and renal prognosis were investigated.Patients with histologically proven IgAN were recruited after informed consent was obtained for the genetic study, which was approved by the ethics committee of our institute. Genomic DNA from each patient was prepared from peripheral blood leucocytes using an automatic DNA isolation system (NA-100, Kurabo, Osaka, Japan). A–C transition at nucleotide −20, G–A transition at −6, C–T transition at +68 and M235T variant at exon two in the AGT gene were determined as described previously.1,2The renal survival rate was analysed for 114 IgAN patients with a creatinine clearance (Ccr) level of 70 mL/min or greater and followed up more than 24 months. The patients with haplotype T235 and C-20 (n = 63) were compared with those without T235 and C-20 (n = 51) for age, sex, blood pressure, proteinuria, serum Cr, Ccr at the time of renal biopsy, drugs administered, and severity of renal histopathologic lesion.Light microscopic evaluation of all specimens was performed in a double blind fashion according to the grading classification described previously, including glomerular cellular proliferation, mesangial matrix increase, global or segmental sclerosis, endocapillary proliferation, leucocyte exudation, duplication of glomerular basement membrane, crescent formation, and tufts adhesion to Bowman’s capsule as well as tubulointerstitial lesions.3The Kaplan-Meier method and the Cox proportional hazards regression model analysed the time course from renal biopsy to end point (initiation of dialysis or sCr level doubled after the time of diagnosis). Several covariates were selected by a stepwise backward method and the effects of these covariates were expressed by a hazard ratio. P 〈 0.05 was considered statistically significant.The genotype distributions in the present study were not different from that in Hardy–Weinberg equilibrium. The genotype and allele frequencies of AGT variants were compatible with previous studies for Japanese population.1,4 Haplotype analysis showed a complete linkage disequilibrium between M235T and A-20C alleles (linkage-disequilibrium coefficient: D′, 1.00). Because the AGT gene variant at −20 was observed only in a subset of the 235T alleles, the following haplotypes were determined: T235 and C-20; T235 and A-20; and M235 and A-20. The incidence of hypertension was not different between each haplotype of AGT.An association study of histopathological findings revealed that patients with haplotype T235 and C-20 had significantly higher grading scores in crescent formation (P = 0.017) than those without haplotype T235 and C-20. Renal survival rate was significantly lower in the patients with haplotype T235 and C-20 (〈link href="#f1"〉Fig. 1, P = 0.003). The Cox proportional hazards regression model showed an increased hazard ratio (HR) for haplotype T235 and C–20 of 5.9 from multivariate analysis (〈link href="#f2"〉Fig. 2; 95% CI, 2.1–16.7; P 〈 0.001). Furthermore, in IgAN patients without administration of angiotensin I converting enzyme inhibitors (n = 77), renal survival rate was significantly lower in those with haplotype T235 and C–20 (P = 0.011).〈figure xml:id="f1"〉1〈mediaResource alt="image" href="urn:x-wiley:13205358:NEP19:NEP_19_f1"/〉Effect of AGT haplotype on the renal survival rate in IgAN patients. Solid and dashed lines represent the renal survival rate in the patients with and without haplotype T235 and C–20, respectively.〈figure xml:id="f2"〉2〈mediaResource alt="image" href="urn:x-wiley:13205358:NEP19:NEP_19_f2"/〉Cox proportional hazards regression model to test the predictors for renal survival time in multivariate analysis. Covariates were selected by stepwise backward analysis. U-protein, urinary protein; HT at renal biopsy, hypertensives at the time of renal biopsy; ACEI, angiotensin I converting enzyme inhibitor. The bars represent the 95% confidence intervals of hazard ratio.This work provides the evidence that the C–20 gene polymorphism of AGT, a subset of 235T alleles, is associated with histopathological severity of glomerular injury, and progression of renal dysfunction in Japanese patient with IgAN.

Notes: Abstract Background. Interleukin-1 (IL-1) has been reported to play a major role in the initiation and progression of several glomerulonephritis, and inhibition of IL-1 by the blockade of IL-1β-converting enzyme (ICE) has been suggested to be an ideal therapeutic strategy. Methods. To examine the effect of ICE inhibition on glomerulonephritis, we examined the susceptibility of ICE-deficient mice (ICE−/−) to anti-glomerular base-ment membrane antibody-induced glomerulonephritis (antiGBMGN), which has been previously reported to be mediated by IL-1β. Results. After the injection of antiGBM antibody to ICE−/− and wild type mice, albuminuria rose progressively and both groups of mice died within 7–9 days. Laboratory analysis of proteinuria, serum creatinine, and glomerular histology revealed no significant difference between the two groups. To pursue the mechanism of this result, bone marrow-derived monocyte/macrophage lineage cells (Mo/Mq cells) were established from both groups and the potency of IL-1β production in response to lipopolysaccharide was examined. An enzyme-linked immunosorbent assay (ELISA) of IL-1β revealed that, Mo/Mq cells from ICE−/− mice secreted IL-1β in response to lipopolysaccharide, although to a lesser extent than the Mo/Mq cells from ICE+/+ mice, suggesting that other protease(s) may process proIL-1β to generate the mature form. In fact, as was seen in the wild type mice, serum from antiGBM-injected ICE−/− mice contained IL-1β. Conclusions. These data suggest a limited effectiveness of ICE inhibition as a therapeutic strategy for glomerulonephritis.

Notes: Abstract The main objective of this study was to assess the blood-brain barrier (BBB) permeability in periventricular areas of the normal mouse brain to test the hypothesis that the fragility of the BBB in periventricular areas may play a role in periventricular white matter lesions. Vascular permeability to intravenously injected horseradish peroxidase (HRP) was examined in the periventricular areas of adult mouse brain using light and electron microscopy. Staining for HRP appeared in the periventricular area adjacent to medial side of the lateral ventricle as well as in BBB-free areas, in the lateral septal nucleus, in the medial portion of the hippocampus and in the dorsal portion of the thalamus. In addition, the staining for HRP appeared in ependymal cell layer located near the choroid plexus and was found early after HRP injection in the wall of some vessels located at medial side of the optic tract. Ultrastructural examination of the vessel wall revealed that staining for HRP in the perfusion-fixed mice after circulation of the tracer for 5 min appeared in the perivascular space, in the basal lamina, in several vesicular profiles of the endothelial cell cytoplasm including abluminal pits, in vesicular profiles of perivascular cells and in the adjacent extracellular space. In the mice perfusion-fixed after HRP circulation for 90 min, staining for HRP in the vessels at medial side of the optic tract appeared in the cytoplasm of the perivascular cells, in vesicular structures of the endothelial cell cytoplasm such as plasmalemmal vesicles, endosomes and multivesicular bodies and occasionally in the vascular basal lamina. No clear staining reaction for HRP was found in the periventricular areas adjacent to lateral side of the lateral ventricles. These findings indicate that the BBB in the periventricular area adjacent to medial side of the lateral ventricle near the root of the choroid plexus is not so tight as it is in the cortex or in the lateral periventricular areas, and suggest that the perivascular cells play a scavenger role in the periventricular area as a component of the BBB. In addition, they indicate that blood-borne macromolecules can also invade the areas adjacent to the ventricles such as the lateral septal nucleus, the medial portion of the hippocampus and the dorsal portion of the thalamus.

Notes: Abstract When 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS) was removed from the mixed CHAPS/EggPC micelles, large vesicles were prepared by dialysis or by slow step-by-step dilution, but small vesicles were prepared by fast one-step dilution. When sodium cholate was removed from the sodium cholate/EggPC micelles, small vesicles formed either by dialysis or by dilution; however, in the presence of 5 mM Ca2+ large vesicles were produced by dialysis, while small vesicles were prepared by dilution. The size growth was related to a detergent-induced fusion of the vesicles containing a large amount of detergent. Using spectrophotometry, quasielastic light scattering and freeze–fracture electron microscopy the fusion events were investigated both through the process of vesicle solubilization by adding detergent and through the process of vesicle formation by diluting a mixed micelle. The results suggest that a rapid CHAPS-induced fusion of the vesicles led to the large resultant vesicles and that no fusion of vesicles containing sodium cholate is responsible for the formation of small vesicles. Furthermore, the ultimate vesicle size related to rapid or slow detergent removal is dependent on the kinetic aspects of the fusion.