Effects of antiplatelet drug dilazep dihydrochloride on anionic sites and extracellular matrix (ecm) components in glomerular basement membrane of stz-induced diabetic rats

A study of anionic sites in the glomerular basement membrane (GBM) of streptozotocin (STZ)-induced diabetic rats with or without treatment by an antiplatelet drug, dilazep dihydrochloride, is described. Expression of glomerular extracellular matrix (ECM) components was examined by immunofluorescence. Renal specimens were immersed in polyethyleneimine (PEI) as a cationic probe and then examined by electron microscopy. Renal specimens were also incubated with rabbit antirat type IV collagen, laminin, and fibronectin antisera and then stained with fluorescein isothiocyanate (FITC)-labeled goat antirabbit IgG antiserum. Mean values of proteinuria in the dilazep-treated diabetic rats were significantly decreased compared with those in nontreated diabetic rats. There was no significant correlation between the levels of proteinuria and those of creatinine clearance (CCr). Number of anionic sites on the GBM in the dilazep-treated diabetic rats were greater than those in diabetic rats. There was no significant difference in the staining of such ECM components between both rat groups. The authors concluded that the dilazep dihydrochloride might prevent anionic charges on the GBM and decrease the urinary excretion of proteins in STZ-induced diabetic rats.     

Altered steady-state levels of mRNA coding for extracellular matrices in renal tissues of ddY mice, an animal model for IgA nephropathy

Correlations between the steady-state mRNA levels of extracellular matrices using specific cDNA probes for the alpha 1 chain of type IV collagen (alpha 1 (IV) chain); laminin A, B1, and B2 chains; and heparan sulfate proteoglycan (HSPG); and glomerular injuries in ddY mice were evaluated. Eight-, sixteen- and forty-week-old ddY mice were used in this study. ICR mice of the same age served as control. Extracted total RNA of pooled kidneys was fixed on a filter and then hybridized with the cDNA probes. Renal cryostat sections were incubated with rabbit anti-mouse type IV collagen, laminin, and HSPG antisera and then stained with FITC-labeled goat anti-rabbit IgG antiserum. The sections were also stained with FITC-labeled goat anti-mouse IgA, IgM, IgG, and C3 antisera. In light microscopy, the average number of glomerular cells was calculated at each age. Increased expression of extracellular matrices genes for the alpha 1(IV) chain; laminin A, B1, and B2 chains; and HSPG was found in renal tissues of ddY mice. Staining of type IV collagen, laminin, and HSPG was observed in renal tissues of ddY mice at each age. Increased proteinuria in 40-week-old ddY mice might be related to the decrease in glomerular basement membrane HSPG which acts as the anionic sites in such areas. Marked proliferation and or expansion of glomerular cells and mesangial matrices were observed in 40 week-old-ddY mice. The intensity of IgA and C3 deposits in the glomeruli was parallel to the levels of mRNA for such components.(ABSTRACT TRUNCATED AT 250 WORDS)     

Proteinuria in passive Heymann nephritis is associated with lipid peroxidation and formation of adducts on type IV collagen.

Passive Heymann nephritis (PHN) is a model of human membranous nephropathy that is characterized by formation of granular subepithelial immune deposits in the glomerular capillary wall which results in complement activation. This is causally related to damage of the filtration barrier and subsequent proteinuria. The local accumulation of injurious reactive oxygen species (ROS) is a major effector mechanism in PHN. ROS may induce tissue damage by initiating lipid peroxidation (LPO). In turn, this leads to adduct formation between breakdown products of LPO with structural proteins, such as formation of malondialdehyde (MDA) or 4-hydroxynonenal-lysine adducts. To examine the role of LPO in the development of proteinuria we have localized MDA and 4-hydroxynonenal-lysine adducts in glomeruli of PHN rats by immunofluorescence microscopy, using specific monoclonal antibodies. By immunogold electron microscopy, MDA adducts were localized to cytoplasmic vesicles and cell membranes of glomerular epithelial cells, to the glomerular basement membrane (GBM), and also to immune deposits. Type IV collagen was specifically identified as being modified by MDA adducts, using a variety of techniques. Collagenase pretreatment of GBM extracts indicated that the NC-1 domain of type IV collagen was a site of adduct formation. When LPO was inhibited by pretreatment of PHN rats with the antioxidant probucol, proteinuria was reduced by approximately 85%, and glomerular immunostaining for dialdehyde adducts was markedly reduced, even though the formation of immune deposits was not affected. By contrast, lowering of the serum cholesterol levels had no influence on the development of proteinuria. These findings are consistent with the premise that ROS-induced glomerular injury in PHN involves LPO and that this results not only in damage of cell membranes but in modification of type IV collagen in the GBM as well. The close temporal correlation of the occurrence of LPO with proteinuria and the ability of probucol to inhibit proteinuria support a causal role for LPO in the the alteration of the glomerular permselectivity which results in proteinuria.     

Significance of serum IgA levels and serum IgA/C3 ratio in diagnostic analysis of patients with IgA nephropathy

Diagnostic analysis of clinical markers including serum IgA levels and serum IgA/C3 ratio in patients with IgA nephropathy is described. One hundred patients with IgA nephropathy (IgA nephropathy group) and 100 patients with other primary glomerular diseases (non-IgA nephropathy group) were examined. The analysis was performed to distinguish between these two groups using four clinical markers: 1) more than five red blood cells in urinary sediments, 2) persistent proteinuria (urinary protein of more than 0.3 g/day), 3) serum IgA levels of more than 315 mg/dl, and 4) a serum IgA/C3 ratio of more than 3.01. Patients with three or four clinical markers were easily diagnosed as having IgA nephropathy in this study. Furthermore, there was a significant difference in these clinical markers between the good prognosis and relatively good prognosis groups (Groups I and II) and the relatively poor prognosis and poor prognosis groups (Groups III and IV) of IgA nephropathy patients. It appears that the presence of microscopic hematuria and/or persistent proteinuria, high serum IgA levels, and the serum IgA/C3 ratio are useful for distinguishing IgA nephropathy from other primary renal diseases. It is postulated that these clinical markers are also useful for diagnosis of IgA nephropathy without renal biopsy.     

IgA肾病86例临床和病理分析

目的 :了解IgA肾病患者的临床表现及其病理情况。方法 :对 1984年 6月～ 2 0 0 0年 12月间经肾活检证实为IgA肾病患者 86例随访资料进行分析。结果 :以感染为首次发病诱因者 4 2例 ,其中呼吸道感染 36例。存在血尿 79例 ,蛋白尿 83例 ;伴高血压 4 0例 ;发生急性肾衰竭 4例。治疗前内生肌酐清除率 (Ccr>70ml/min 6 2例 ,5 0～ 70ml/min 15例 ,2 5～ 5 0ml/min 8例 ,<2 5ml/min 1例 ;治疗后Ccr>70ml/min 73例 ,5 0～ 70ml/min 5例 ,2 5～ 5 0ml/min 4例 ,<2 5ml/min 4例。除肾小球系膜增生外 ,病理改变以间质炎症和肾小球硬化出现的比例最高 ,其次为肾小管萎缩、间质纤维化等。结论 :IgA肾病的临床表现以蛋白尿和血尿多见 ,且两者合并存在的机会多见 ;部分患者可出现血压升高及肾功能恶化。IgA肾病患者应早期进行肾活检检查     

102例IgA肾病蛋白尿与病理临床分析

目的探讨蛋白尿对IgA肾病病理改变和临床指标的影响及其相关性。方法回顾性分析郑州大学第一附属医院肾内科102例IgA肾病患者的病理和临床资料,探讨其相关性。结果蛋白尿与牛津分型中毛细血管内增生、节段性的肾小球硬化、肾小管萎缩/间质纤维化、球性硬化、新月体病变的病理改变存在相关性,与肾功能、免疫荧光分型存在相关性,而与高血压、血清IgA、C3水平不存在相关性。结论随着蛋白尿的增多,肾脏毛细血管内增生、肾小管萎缩/间质纤维化、球性硬化等病理改变加重,且肾功能也会随之恶化。     

Fabry病合并IgA肾病临床病理特点分析

目的总结Fabry病合并IgA肾病的临床病理特点。方法回顾性分析2例Fabry病合并IgA肾病患者的临床资料。结果2例患者均为男性,1例表现为蛋白尿并镜下血尿,高血压,肾功能正常;1例表现为蛋白尿,肾功能正常;2例外周血α-半乳糖苷酶A活性均较正常降低;光镜下均见肾小球足细胞空泡变性呈蜂窝状,足细胞胞质内见嗜甲苯胺蓝颗粒;电镜下足细胞胞质内大量髓样小体;均有肾小球系膜增生病变,伴有IgA弥漫颗粒状沉积于系膜区。结论Fabry病合并IgA肾病临床表现缺乏特异性,但具有特征性病理形态学改变,肾组织活检是确诊主要依据。     

Detection of platelets in urinary sediments from patients with “Advanced” stages of immunoglobulin a nephropathy

The presence of platelets in urinary sediments was studied by an immunofluorescence method in patients with immunoglobulin A (IgA) nephropathy. The aim of the present study was to determine if the presence of platelets in urinary sediments is correlated with glomerular injuries in patients with IgA nephropathy. Sixteen patients with IgA nephropathy and eight with diffuse proliferative glomerulo nephritis (DPGN) were examined. This study showed a significant correlation between the number of platelets found in urinary sediments and the severity of glomerular injuries in patients with IgA nephropathy. It was suggested that detection of platelets in urinary sediments is useful in evaluating the degree of histopathological changes and/or prognosis in IgA nephropathy prior to renal biopsy.     

膜型IgA肾病

肾病是我国常见的肾小球疾病，病理类型很多，但膜型ＩｇＡ肾病极罕见。本文报告３例膜型ＩｇＡ肾病。病理特点是系膜增生的同时，肾小球毛细血管基底膜增厚，并有钉突形成。患者有大量蛋白尿。系膜区有大量ＩｇＡ沉积，毛细血管基底膜外侧有ＩｇＧ沉积。超微结构显示在系膜区及基底膜上皮细胞下均有电子致密物。本文通过免疫荧光和免疫电镜的研究认为，膜型ＩｇＡ肾病是膜型肾小球肾炎与系膜增生型ＩｇＡ肾病的相互重叠。     

Preservation of mesangium and immunohistochemically defined antigens in glomerular basement membrane isolated by detergent extraction.

To define the characteristics of isolated glomerular basement membrane (GBM), immunohistochemical and morphometric analyses have been carried out on rat and human tissues. Site-specific arrays of antigens were identified in detergent-isolated GBM in a distribution similar to that observed in intact kidney. In the human, fibronectin, procollagen IV, and collagen V were observed along the internal aspect of GBM continuous with antigenic sites in the mesangium. Another array of antigens was identified in the GBM but not within the mesangium--Goodpasture's antigen, bovine lens capsule type IV collagen, and amyloid P component. In addition, sites reactive with rabbit antiserum to laminin were present on both sides of the lamina densa as well as within the mesangial region. Actomyosin, a presumed mesangial cell antigen persisted in the mesangium of isolated GBM. Mesangial matrix was identified in detergent-isolated GBM in an amount equivalent to that present in intact glomeruli. Sonicated GBM contained the same antigens but it was not possible to quantitate the amount of mesangial material by immunofluorescence or morphometric analysis. The thickness of the lamina densa was greater in sonicated and detergent-treated rat GBM preparations than in native rat kidney. These studies demonstrated that isolated GBM is heterogeneous with respect to its antigenic constituents and in addition contains mesangial matrix, which is morphologically and immunohistochemically distinct from peripheral GBM.     

Relationship between levels of urinary type IV collagen and renal injuries in patients with IgA nephropathy

Because type IV collagen is synthesized by podocytes and mesangial cells, we investigated the relationship between levels of urinary type IV collagen (uIV) and renal injuries in patients with IgA nephropathy. uIV was measured by a highly sensitive one-step sandwich enzyme immunoassay prior to renal biopsy. Patients with IgA nephropathy were classified into four grades (grade 1 = good prognosis, grade 2 = relatively good prognosis, grade 3 = relatively poor prognosis, and grade 4 = poor prognosis) by the prognostic criteria of the Ministry of Health, Labor, and Welfare of Japan. Levels of uIV in grade 4 were significantly higher than those in grades 1-3. These levels tended to increase gradually due to progression of renal injuries. The grades were further divided into two groups: group I (good or relatively good prognoses) and group II (relatively poor or poor prognoses). Patients with proteinuria of <1.0 g/day were defined as groups Ip and IIp. The levels of uIV in group II were significantly higher than those in group I, and those in group IIp were significantly higher than those in group Ip. It appears that the level of uIV can be a useful marker for detection of renal injuries in IgA nephropathy.     

Antibodies to basement membrane collagen and to laminin are present in sera from patients with poststreptococcal glomerulonephritis

Sera from patients with poststreptococcal glomerulonephritis (PSGN) known to have antibodies to proteoglycans were studied for the presence of antibodies against other basement membrane (BM) components. BM collagen (type IV) was isolated in the native state by extracting bovine anterior lens capsule (ALC) with 0.5 M acetic acid. The 7-S (collagenous) domain and the NC-1 (noncollagenous) domain of type IV collagen were obtained after bacterial collagenase digestion of ALC followed by gel filtration. Laminin was isolated from the mouse EHS tumor and fibronectin from human plasma. Immunologic studies, using an ELISA and electroimmunoblot, revealed the presence of antibodies that reacted with intact, native type IV collagen and the 7-S collagenous domain of this molecule. Reaction with the NC-1 (noncollagenous) domain was minimal, and not higher than that obtained with control sera. Laminin reaction strongly with the patients' sera, but fibronectin did not. Unlike sera from patients with Goodpasture syndrome, which contain antibodies primarily against the NC-1 (noncollagenous) domain of type IV collagen, sera from patients with acute PSGN contain antibodies against all the major macromolecular components of BM. This difference in immunologic reactivity may account for the observed differences in the pathologic picture at the glomerular level.     

328例肾脏疾病患者的肾脏病理分析

目的：了解近年经皮肾活检肾脏疾病患者的病理类型分布及其与临床症状的关系。方法：回顾分析2004年6月～2005年6月间因肾脏疾病住院行肾活检的患者的临床病理特点。结果：328例肾脏疾病中，原发性肾小球疾病257例（78．4％）、小管间质疾病16例（4．9％）、继发性肾脏病55例（16．8％）。原发性肾小球疾病中IgA肾病137例，占53．3％；继发性肾小球肾炎中狼疮肾炎、紫癜性肾炎和高血压肾损害较多，分别占32．7％、27．3％和18．2%；小管间质疾病以急性间质性肾炎为多，占68．8％。IgA肾病主要表现为蛋白尿并血尿；膜性肾病、高血压肾病主要表现为单纯性蛋白尿。单纯血尿主要病理类型是IgA肾病；单纯蛋白尿主要病理类型是IgA肾病和轻微病变。蛋白尿并血尿主要病理类型是IgA肾病、轻微病变和狼疮性肾炎；大量蛋白尿主要病理类型是轻微病变、IgA肾病和膜性肾病。结论：本组资料显示原发性肾小球疾病仍为我国最常见的肾脏疾病，其中以IgA肾病最常见；小管间质疾病发病率有增高，继发性肾脏病以狼疮肾炎最常见，其它特殊肾脏病有增加。     

280例IgA肾病患者不同年龄组病理分析

目的：回顾性分析不同年龄组IgA。肾病患者的病理改变特点,以利于早期诊断和治疗。方法：将我院280例（2005-2007年）经皮肾活检确诊为原发性IgA。肾病的患者按不同年龄分为儿童组、青少年组和成人组,逐项分析病例组织光镜和免疫荧光检查的相关资料。结果：在280例病理资料中,儿童组患者病理学分级以I～Ⅱ级为主,免疫荧光检查以单纯IgA和或C3沉积多见;青少年组患者病理学分级以I～Ⅲ级为主,免疫荧光检查也是以单纯IgA和或C3沉积多见;成人组病理学改变从I～Ⅳ级均可见到,主要以Ⅲ～Ⅳ级为主,免疫荧光检查以单纯IgA、IgA＋IgM和或C3沉积较多。结论：IgA肾病的病理改变有随着年龄增大,病理改变越明显肾脏损害越严重的趋势,早期进行经皮肾活检有利于明确诊断及尽早治疗。     

IgA nephropathy in a patient with dominant dystrophic epidermolysis bullosa

Dystrophic epidermolysis bullosa (DEB) is a rare and severe hereditary dermatosis. On the other hand, IgA nephropathy is the most common form of glomerulonephritis in childhood and adults, and clinically characterized by microhematuria and proteinuria and histologically by deposition of immunoglobulin A in mesangial lesions. Several renal complications of recessive DEB including IgA nephropathy and amyloidosis have been reported. However, there have been no reports on dominant DEB associated with IgA nephropathy. We report here for the first time a 17-year-old girl with dominant DEB associated with IgA nephropathy. The patient has suffered from episodes of urinary, upper airway, and skin infections. At 17 years of age, proteinuria and hematuria were detected, with a high value of serum IgA. Renal biopsy was performed, and immunofluorescence microscopic examination revealed segmental deposits of IgA in mesangial lesions, with many glomeruli exhibiting diffuse segmental mesangial-proliferative glomerulonephritis. We diagnosed dominant DEB associated with IgA nephropathy on the basis of proteinuria, hematuria, and deposits of IgA in mesangial lesions on immunofluorescence microscopic examination, and diffuse segmental mesangial-proliferative glomerulonephritis. These findings suggest that repeated skin infections might have contributed to the pathogenesis of IgA nephropathy in this patient.     

环孢素联合糖皮质激素治疗IgA肾病的研究

目的观察环孢素联合糖皮质激素治疗以大量蛋白尿（蛋白尿≥3.5g/d）为主要表现的IgA肾病的临床效果。方法34例符合条件的IgA肾病患者随机入组环孢素联合激素治疗组（观察组,18例）和糖皮质激素治疗组（对照组,16例）,记录并比较两组患者治疗6个月时的24h尿蛋白定量、血清白蛋白、血清肌酐及肾小球滤过率等指标,并观察两组患者的不良反应。结果两组患者治疗6个月时的24h尿蛋白定量较治疗前显著下降（P均〈0.05）,血清白蛋白水平较治疗前显著升高（P均〈0.05）,治疗前后血清肌酐水平及eGFR水平差异均无统计学意义,且两组间总有效率的差异无统计学意义（P=0.311）。两组均无因发生不良反应而退出研究者。结论环孢素联合糖皮质激素治疗以大量蛋白尿为主要表现的IgA肾病较单纯激素治疗起效快、疗效好,且不良反应少。     

Oxidative metabolism of polymorphonuclear leukocytes (PMN) in patients with IgA nephropathy

The production of hydrogen peroxide (H₂O₂) by neutrophilic polymorphonuclear leukocytes (PMN) after stimulation and the infiltration of PMN in glomeruli were determined in 20 patients with primary IgA nephropathy. The H₂O₂ production of PMN after the stimulation was measured with a spectrophotometer using horseradish peroxidase as substrate. The results were as follows: (1) when PMN were pretreated with cytochalasine B, H₂O₂ production after stimulation with heataggregated IgG (IgG) or serum-treated zymosan (STZ) was significantly higher in patients with IgA nephropathy than in controls, and (2) there was an increased amount of PMN localized in glomeruli in patients with IgA nephropathy using immunofluorescence of monoclonal anti-PMN antibody. It appeared that the increased renal infiltration of PMN which have a high potential for production of reactive oxygen species might induce the glomerular injuries in patients with IgA nephropathy.     

Follow-up study on urinary type IV collagen in patients with early stage diabetic nephropathy

Type IV collagen is a major component released from the glomerular and tubular basement membranes. To investigate the alteration of renal type IV collagen turnover in early stage diabetic nephropathy, urinary type IV collagen was measured by a highly sensitive one-step sandwich enzyme immunoassay (EIA). Urinary samples were obtained from 94 diabetic patients without overt proteinuria. Among those patients, 61 were normoalbuminuric and 33 patients were in the microalbuminuric group. Levels of urinary type IV collagen were serially examined at the start of this study and again one year later. The levels of urinary type IV collagen in patients in the microalbuminuric group were significantly higher than those in the normoalbuminuric group (P < 0.01). There was a significant correlation between the concentration of urinary albumin and urinary type IV collagen in both groups (P < 0.05). Twenty-eight patients (45.3%) in the normoalbuminuric group who showed an abnormal elevation of urinary type IV collagen in comparison to the reference range of normal healthy adults (normal range; less than 3.5 μg/g · Cr). Seven (25%) out of these 28 normoalbuminuric patients with increased urinary type IV collagen progressed to the microalbuminuric group one year later. The levels of urinary type IV collagen in such patients were significantly increased. In the 21 patients who stayed within the normoalbuminuric group, the urinary type IV collagen levels were significantly decreased one year later. It appears that the levels of urinary type IV collagen might reflect ongoing alteration of the extracellular matrix (ECM) turnover and might define more specifically the early stage diabetic nephropathy than the detection of microalbuminuria. It is concluded that the serial measurement of urinary type IV collagen can be a useful marker for detecting renal injury in diabetes. J. Clin. Lab. Anal. 12:378–382, 1998. © 1998 Wiley-Liss, Inc.     

Urinary albumin excretion: a predictor of glomerular findings in adults with microscopic haematuria

BACKGROUND: Microscopic haematuria without proteinuria is a common clinical finding. When urological causes are excluded, usual findings on renal biopsy are IgA nephropathy (which can progress to end-stage renal failure) or thin basement membrane nephropathy (which has an excellent prognosis). A non-invasive test to discriminate between the two would be useful. Aim: To examine the value of measurement of urinary albumin excretion in discriminating glomerular causes of microscopic haematuria in patients without proteinuria on urine dipstick tests. DESIGN: Single-centre retrospective cross-sectional observational study. METHODS: Adult patients who underwent renal biopsy for microscopic haematuria over a 6-year period from January 1994 were identified. Study entry required normal renal function, no proteinuria detected by dipstick, and urinary albumin excretion <300 mg/24 h. Patients with IgA nephropathy had follow-up for a mean of 58 months after biopsy. RESULTS: Of 169 patients fulfilling study criteria, 119 (70%) had normoalbuminuria (<30 mg/24 h); 52 (30%) had microalbuminuria (30-299 mg/24 h). Of those with normoalbuminuria, 106 (89%) had thin basement membrane nephropathy or no glomerular abnormality. Thirteen (11%) had IgA nephropathy, and of 12 of these followed-up for a mean 64 months, none developed overt, dipstick-positive proteinuria. In contrast, 24 (48%) of those with microalbuminuria had IgA nephropathy, and of 22 followed-up for a mean 55 months, five developed overt proteinuria. DISCUSSION: Urinary albumin excretion is an indicator of likely glomerular findings in microscopic haematuria, and may influence whether a renal biopsy is necessary.     

554例IgA肾病患者临床特征分析

目的 探讨IgA肾病的特征及不同肾功能分期的临床特点。方法 选取经临床和肾脏病理明确诊断为IgA肾病的患者,收集所有病例的一般情况及临床资料,分析不同年龄层IgA肾病患者临床表现分布、不同慢性肾脏病（CKD）分期患者的临床特点,以及进展性肾功能不全IgA肾病患者的血清肌酐水平与临床各指标的相关性。结果 共纳入554例I...