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Shuji Kondo

Publications and source records attributed to Shuji Kondo.

18 recordsLinked to original sources

Bcl-2 expression modulates cell adhesion and migration promoting branching of ureteric bud cells.

Bcl-2 is the founding member of a family of proteins that influence apoptosis. During kidney development bcl-2 not only acts as a survival factor, but may also impact cell adhesive mechanisms and by extension branching morphogenesis. The interrelationship between cell adhesion, migration and apoptosis, important during development, is poorly understood. Here we examined the impact lack of bcl-2, an inhibitor of apoptosis, has on ureteric bud (UB) cell adhesion, migration, and branching morphogenesis. Bcl-2 -/- UB cells demonstrated increased cell migration, increased cell invasion and decreased adhesion to vitronectin and fibronectin compared with wild-type cells. Bcl-2 +/+ UB cells readily branched in collagen gel and Matrigel while bcl-2 -/- UB cells did not undergo significant branching in either matrix. Re-expression of bcl-2 in bcl-2 -/- UB cells restored their ability to undergo branching morphogenesis in Matrigel. Consistent with our in vitro data, we show that in the absence of bcl-2, embryonic kidneys undergo decreased UB branching. We observed decreased numbers of UB branch points, UB branch tips and a decreased distance to the first UB branch point in the absence of bcl-2. The alterations in bcl-2 -/- UB cell adhesion and migration was also associated with a significant alteration in expression of a number of extracellular matrix proteins. Bcl-2 -/- UB cells exhibited increased fibronectin expression and decreased thrombospondin-1 and osteopontin expression. Taken together, these data suggest that bcl-2 is required for the proper regulation of cell adhesive and migratory mechanisms, perhaps through modulation of the cellular microenvironment.

Animals↗

Role of integrin-linked kinase in epithelial-mesenchymal transition in crescent formation of experimental glomerulonephritis.

BACKGROUND: Glomerular parietal epithelial-mesenchymal transition (EMT) is a key event in crescent formation of glomerulonephritis (GN). Integrin-linked kinase (ILK) is an integrin cytoplasmic-binding protein that has been implicated in the regulation of cell adhesion, extracellular matrix organization and EMT. Transforming growth factor-beta (TGF-beta) is involved in the induction and progression of EMT in several tissues. METHODS: To investigate whether ILK is involved in the crescent formation in GN, we studied the expression of ILK protein and activity in crescentic GN induced in Wistar Kyoto (WKY) rats. In addition, we investigated whether transforming growth factor-beta1 (TGF-beta1) could induce glomerular EMT and ILK by using cultured parietal epithelial cell (PEC). RESULTS: The expression of ILK was strongly induced in cellular crescents at day 7 and followed by a decrease in fibrocellular crescents at day 28. ILK-expressing cells in cellular crescents were double-positive for protein gene product 9.5 (PEC marker), alpha-smooth muscle actin (alpha-SMA, myofibroblasts marker) and TGF-beta1, indicating a possible contribution of ILK and TGF-beta1 to EMT in crescent formation in GN. Consistent with the finding of histological ILK expression in crescents, western blot and kinase activity assay showed an increase in both ILK protein and activity, peaking at day 7 of GN (3.7- and 3.5-fold of control, respectively). The expression of ILK increased to 3.1-fold of control when EMT was induced in cultured PEC by TGF-beta1. CONCLUSION: The present results provide the first evidence that expression and activity of ILK are increased in cellular crescents of experimental GN. Enhanced expression and activity of ILK, possibly by TGF-beta1, is associated with the induction of EMT by PEC and thereby, may participate in the formation of cellular crescents in GN.

Animals↗

Addition of the antioxidant probucol to angiotensin II type I receptor antagonist arrests progressive mesangioproliferative glomerulonephritis in the rat.

Angiotensin II (Ang II) and reactive oxidative species (ROS) that are produced by NADPH oxidase have been implicated in the progression of glomerulonephritis (GN). This study examined the effect of simultaneously interrupting Ang II and ROS with an Ang II receptor blocker (ARB), candesartan, and a free radical scavenger, probucol, in a model of progressive mesangioproliferative GN induced by the injection of anti-Thy-1 antibody into uninephrectomized rats. Nephritic rats were divided into four groups and given daily oral doses of the following: Vehicle, 1% probucol diet, 70 mg/L candesartan in drinking water, and probucol plus candesartan. These treatments lasted until day 56. Vehicle-treated nephritic rats developed progressively elevated proteinuria and glomerulosclerosis. Candesartan kept proteinuria significantly lower than vehicle or probucol. The addition of probucol to candesartan normalized urinary protein excretion. Increases in BP in nephritic rats were lowered by these treatments, except with probucol. It is interesting that both glomerular cell number and glomerulosclerosis were significantly decreased by candesartan and normalized by the addition of probucol. Immunohistochemical studies for TGF-beta1, collagen type I, and fibronectin revealed that the combined treatment abolished glomerular fibrotic findings compared with candesartan. In addition, glomerular expression of NADPH oxidase components and superoxide production suggested that the combined treatment completely eliminated NADPH oxidase-associated ROS production. In conclusion, our study provides the first evidence that the antioxidant probucol, when added to an Ang II receptor blockade, fully arrests proteinuria and disease progression in GN. Furthermore, the data suggest that NADPH oxidase-associated ROS production may play a pivotal role in the progression of GN. The combination of probucol and candesartan may represent a novel route of therapy for patients with progressive GN.

Angiotensin II Type 1 Receptor Blockers↗

Up-regulation of integrin-linked kinase activity in rat mesangioproliferative glomerulonephritis.

This study investigated whether integrin-linked kinase (ILK) is involved in the pathogenesis of chronic glomerulonephritis (GN) by analyzing the expression and activity of glomerular ILK in a chronic rat model of mesangioproliferative GN. Double immunostaining of kidneys obtained at different time points with glomerular cell-specific markers revealed that ILK was primarily expressed by glomerular epithelial cells, and weakly by mesangial cells (MCs) and endothelial cells in control rats, but dramatically increased in a typical mesangial pattern at days 21 and 28 of GN. Semiquantitative assessment indicated that the level of glomerular ILK expression closely parallels the level of accumulation of glomerular extracellular matrix (ECM) as well as fibronectin (FN). Immunoprecipitation and kinase activity assays using isolated nephritic glomeruli indicated a striking increase of ILK activity on days 21 and 28 of GN. Further, cultured rat MCs overexpressing kinase-deficient ILK diminished FN assembly and collagen matrix remodeling as compared with control transfectants. The results showed that glomerular ILK expression and activity are markedly increased in an experimental model of chronic GN. Increased activity of ILK in MCs may contribute to the development of chronic mesangial alterations leading to glomerular scarring.

Animals↗

Hangover susceptibility in relation to aldehyde dehydrogenase-2 genotype, alcohol flushing, and mean corpuscular volume in Japanese workers.

BACKGROUND: A study of Asian-American students suggested a positive association between inactive ALDH2*2 and susceptibility to hangover. A biomarker for moderate-to-heavy drinking in persons with inactive aldehyde dehydrogenase-2 (ALDH2) is increased mean corpuscular volume (MCV). METHODS: Associations between hangover and ALDH2 genotype, alcohol flushing, and MCV were examined for 251 Japanese workers (139 men, 112 women). RESULTS: Inactive ALDH2*1/2*2 heterozygotes drank less alcohol than active ALDH2*1/2*1 homozygotes (p < 0.0001), but the frequency of hangover did not significantly differ between the two groups for either gender. The amount of drinking reported to lead to hangover was significantly less for male and female ALDH2*1/2*2 heterozygotes than for their ALDH2*1/2*1 homozygous counterparts (p < 0.005). The proportion of men who had hangover three times or more during the past year increased significantly with increased daily alcohol consumption in men with the ALDH2*1/2*2 genotype (p = 0.0002) but not in those with the ALDH2*1/2*1 genotype. For men who usually consumed <44 g of ethanol/day, the median amount of drinking before hangover was significantly lower for ALDH2*1/2*2 men than for ALDH2*1/2*1 men reporting the same level of consumption. Hangover occurred with consistently high frequency among ALDH2*1/2*1 men, regardless of their daily consumption. Similar findings were observed in a comparison of men who never flushed and those who reported current or former flushing, a surrogate marker of inactive ALDH2. Assessment of hangover risk by quartiles of MCV showed that men with MCV of > or =96 had a significantly higher risk of hangover than did men with MCV of <91 (odds ratio = 5.56; 95% confidence interval = 1.69-18.25). CONCLUSIONS: Inactive heterozygous ALDH2, alcohol flushing, and increased MCV were positively associated with hangover susceptibility in Japanese workers, suggesting that acetaldehyde is etiologically linked to the development of hangover.

Adult↗

Nitrite is an alternative source of NO in vivo.

In this study, we investigated whether orally administered nitrite is changed to NO and whether nitrite attenuates hypertension in a dose-dependent manner. We utilized a stable isotope of [15N]nitrite (15NO2-) as a source of nitrite to distinguish between endogenous nitrite and that exogenously administered and measured hemoglobin (Hb)-NO as an index of circulating NO in whole blood using electron paramagnetic resonance (EPR) spectroscopy. When 1 mg/kg Na15NO2 was orally administered to rats, an apparent EPR signal derived from Hb15NO (A(Z) = 23.4 gauss) appeared in the blood. The peak blood HbNO concentration occurred at the first measurement after intake (5 min) for treatment with 1 and 3 mg/kg (HbNO: 4.93 +/- 0.52 and 10.58 +/- 0.40 microM, respectively) and at 15 min with 10 mg/kg (HbNO: 38.27 +/- 9.23 microM). In addition, coadministration of nitrite (100 mg/l drinking water) with N(omega)-nitro-L-arginine methyl ester (L-NAME; 1 g/l) for 3 wk significantly attenuated the L-NAME-induced hypertension (149 +/- 10 mmHg) compared with L-NAME alone (170 +/- 13 mmHg). Furthermore, this phenomenon was associated with an increase in circulating HbNO. Our findings clearly indicate that orally ingested nitrite can be an alternative to L-arginine as a source of NO in vivo and may explain, at least in part, the mechanism of the nitrite/nitrate-rich Dietary Approaches to Stop Hypertension diet-induced hypotensive effects.

Administration, Oral↗

Transforming growth factor-beta1 stimulates collagen matrix remodeling through increased adhesive and contractive potential by human renal fibroblasts.

Renal tubulointerstitial fibrosis is the common final pathway leading to end-stage renal failure. Tubulointerstitial fibrosis is characterized by fibroblast proliferation and excessive matrix accumulation. Transforming growth factor-beta1 (TGF-beta1) has been implicated in the development of renal fibrosis accompanied by alpha-smooth muscle actin (alpha-SMA) expression in renal fibroblasts. To investigate the molecular and cellular mechanisms involved in tubulointerstitial fibrosis, we examined the effect of TGF-beta1 on collagen type I (collagen) gel contraction, an in vitro model of scar collagen remodeling. TGF-beta1 enhanced collagen gel contraction by human renal fibroblasts in a dose- and time-dependent manner. Function-blocking anti-alpha1 or anti-alpha2 integrin subunit antibodies significantly suppressed TGF-beta1-stimulated collagen gel contraction. Scanning electron microscopy showed that TGF-beta1 enhanced the formation of the collagen fibrils by cell attachment to collagen via alpha1beta1 and alpha2beta1 integrins. Flow cytometry and cell adhesion analyses revealed that the stimulation of renal fibroblasts with TGF-beta1 enhanced cell adhesion to collagen via the increased expression of alpha1 and alpha2 integrin subunits within collagen gels. Fibroblast migration to collagen was not up-regulated by TGF-beta1. Furthermore, TGF-beta1 increased the expression of a putative contractile protein, alpha-SMA, by human renal fibroblasts in collagen gels. These results suggest that TGF-beta1 stimulates fibroblast-collagen matrix remodeling by increasing both integrin-mediated cell attachment to collagen and alpha-SMA expression, thereby contributing to pathological tubulointerstitial collagen matrix reorganization in renal fibrosis.

Actinin↗

Transforming growth factor-beta in renal disease with glycogen storage disease I.

We report a 14-year-old patient with Japanese glycogen storage disease I (GSD-I) who was found to have proteinuria. Renal biopsy revealed massive tubular atrophy and interstitial fibrosis with mononuclear cell infiltration, but the glomeruli were almost normal. The epithelial cells of tubules contained periodic acid-Schiff-positive glycogen deposits digested by diastase. In an immunohistological study, transforming growth factor (TGF)-beta expression was increased in tubular epithelial cells compared with a normal control kidney specimen. These data suggest that increased TGF-beta expression is involved in the pathophysiology of renal interstitial fibrosis in a patient with GSD-I.

Adolescent↗

Possible contributions of reactive oxygen species and mitogen-activated protein kinase to renal injury in aldosterone/salt-induced hypertensive rats.

Studies were performed to test the hypothesis that reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) contribute to the pathogenesis of aldosterone/salt-induced renal injury. Rats were given 1% NaCl to drink and were treated with one of the following combinations for 6 weeks: vehicle (0.5% ethanol, SC, n=6); aldosterone (0.75 microg/H, SC, n=8); aldosterone plus a selective mineralocorticoid receptor antagonist; eplerenone (0.125% in chow, n=8); aldosterone plus an antioxidant; and tempol (3 mmol/L in drinking solution, n=8). The activities of MAPKs, including extracellular signal-regulated kinases (ERK)1/2, c-Jun-NH2-terminal kinases (JNK), p38MAPK, and big-MAPK-1 (BMK1) in renal cortical tissues were measured by Western blot analysis. Aldosterone-infused rats showed higher systolic blood pressure (165+/-5 mm Hg) and urinary excretion of protein (106+/-24 mg/d) than vehicle-infused rats (118+/-3 mm Hg and 10+/-3 mg/d). Renal cortical mRNA expression of p22phox, Nox-4, and gp91phox, measured by real-time polymerase chain reaction, was increased in aldosterone-infused rats by 2.3, 4.3, and 3.0-fold, respectively. Thiobarbituric acid-reactive substances (TBARS) content in renal cortex was also higher in aldosterone (0.23+/-0.02) than vehicle-infused rats (0.09+/-0.01 nmol/mg protein). ERK1/2, JNK, and BMK1 activities were significantly elevated in aldosterone-infused rats by 3.3, 2.3, and 3.0-fold, respectively, whereas p38MAPK activity was not changed. Concurrent administration of eplerenone or tempol to aldosterone-infused rats prevented the development of hypertension (127+/-2 and 125+/-5 mm Hg), and the elevations of urinary excretion of protein (10+/-2 and 9+/-2 mg/day) or TBARS contents (0.08+/-0.01 and 0.11+/-0.01 nmol/mg protein). Furthermore, eplerenone and tempol treatments normalized the activities of ERK1/2, JNK, and BMK1. These data suggest that ROS and MAPK play a role in the progression of renal injury induced by chronic elevations in aldosterone.

Aldosterone↗

Sisters with alpha-mannosidosis and systemic lupus erythematosus.

UNLABELLED: Alpha-mannosidosis is an autosomal recessive disorder caused by deficiency of lysosomal alpha-mannosidase (LAMAN). Here, we report two sisters with alpha-mannosidosis who developed systemic lupus erythematosus (SLE). The sisters were both homozygous for a one bp deletion within the LAMAN gene resulting in a truncated gene product. The coincidence of alpha-mannosidosis and SLE are discussed with regard to both clinical and molecular findings. CONCLUSION: alpha-mannnosidosis may contribute to the onset of systemic lupus erythematosus in predisposed patients.

Adult↗

PDGF-BB enhances alpha1beta1 integrin-mediated activation of the ERK/AP-1 pathway involved in collagen matrix remodeling by rat mesangial cells.

Platelet-derived growth factor-BB (PDGF-BB) has been implicated in the pathogenesis of progressive glomerulonephritis (GN). Previous studies have reported that PDGF-BB stimulates mesangial cells (MCs)-induced collagen matrix remodeling through enhancement of alpha1beta1 integrin-dependent migratory activity. To determine the cell signaling pathway responsible for abnormal MC-related mesangial matrix remodeling in progressive GN, we studied the involvement of the extracellular signal-regulated kinase (ERK)/activator protein-1 (AP-1) pathway in PDGF-BB-enhanced collagen gel contraction. Western blotting and gel shift assay revealed that MC-induced gel contraction resulted in ERK activation in parallel with that of AP-1 binding, peaking at 4 h and lasting at least for 24 h. Application of the MEK inhibitor, U0126, and the c-jun/AP-1 inhibitor, curcumin, inhibited gel contraction and AP-1 activity, respectively, dose dependently. PDGF-BB enhanced not only gel contraction but ERK phosphorylation and AP-1 activity by MCs. Marked inhibitory effects on PDGF-BB-induced gel contraction and ERK/AP-1 activity were observed in the presence of either function blocking anti-alpha1- or anti-beta1-integrin antibody or U0126. Consistently, AP-1-inactive MCs expressing a dominant-negative mutant of c-jun showed a significant decrease of PDGF-BB-induced gel contraction as compared with mock-transfected MCs. Finally, migration assay showed that ERK/AP-1 activity is required for PDGF-BB-stimulated alpha1beta1 integrin-dependent MC migration to collagen I. These results indicated that PDGF-BB enhances alpha1beta1 integrin-mediated collagen matrix reorganization through the activation of the ERK/AP-1 pathway that is crucial for MC migration. We conclude that the ERK/AP-1 pathway plays an important role in PDGF-BB-induced alpha1beta1 integrin-dependent collagen matrix remodeling; therefore, the inhibition of its pathway may provide a novel approach to regulate abnormal collagen matrix remodeling in progressive GN.

Animals↗

The SOD mimetic tempol ameliorates glomerular injury and reduces mitogen-activated protein kinase activity in Dahl salt-sensitive rats.

It was shown recently that renal injury in Dahl salt-sensitive (DS) hypertensive rats is accompanied by mitogen-activated protein kinase (MAPK) activation. The present study was conducted to elucidate the contribution of reactive oxygen species to MAPK activities and renal injury in DS rats. DS rats were maintained on high salt (H; 8.0% NaCl; n = 7) or low salt (L; 0.3% NaCl; n = 6) diets; H + a superoxide dismutase mimetic, tempol (3 mmol/L in drinking water; n = 8); or H + hydralazine (0.5 mmol/L in drinking water; n = 8) for 4 wk. Mean BP (MBP) in DS/H and DS/L rats was 185 +/- 7 and 113 +/- 3 mmHg, respectively. DS/H rats showed a higher ratio of urinary protein excretion and creatinine (U(protein)V/U(cr)V; 20.3 +/- 1.1) and a higher cortical collagen content (22 +/- 1 micro g/mg) than in DS/L rats (2.4 +/- 0.1 and 13 +/- 1 micro g/mg, respectively). The expression of p22-phox and Nox-1, essential components of NAD(P)H oxidase, in renal cortical tissue was approximately threefold higher in DS/H rats than in DS/L rats. Increased activities of renal cortical MAPK, including extracellular signal-regulated kinases (ERK) 1/ERK2 and c-Jun NH(2)-terminal kinases (JNK) were also observed in DS/H rats by 7.0 +/- 0.7- and 4.3 +/- 0.2-fold, respectively. Tempol treatment significantly decreased MBP (128 +/- 3 mmHg), U(protein)V/U(cr)V (4.8 +/- 0.4), and cortical collagen content (14 +/- 1 micro g/mg) and normalized ERK1/ERK2 and JNK activities in DS/H rats. Histologically, tempol markedly ameliorated progressive sclerotic and proliferative glomerular changes in DS/H rats. Hydralazine-treated DS/H rats showed similar MBP (127 +/- 5 mmHg) to tempol-treated DS/H rats. Hydralazine also decreased U(protein)V/U(cr)V (16.2 +/- 1.5) and cortical collagen content (19 +/- 1 micro g/mg) in DS/H rats. However, these values were significantly higher than those of tempol-treated rats. Furthermore, although hydralazine significantly reduced JNK activity (-56 +/- 3%), ERK1/ERK2 activities were unaffected. These data suggest that reactive oxygen species, generated by NAD(P)H oxidase, contribute to the progression of renal injury through ERK1/ERK2 activation in DS/H hypertensive rats.

Animals↗

Beta1-integrins and glomerular injury.

The renal glomerulus is composed of three types of glomerular cells (mesangial cell (MC), endothelial cell and podocyte) and extracellular matrix (ECM) consisting of the glomerular basement membrane (GBM) and mesangial matrix. It constitutes a highly specialized microcirculation in which the permeability characteristics of the capillary wall allow its unique filtration function. The proliferation of MCs, an increase of mesangial ECM and detachment podocyte from GBM are key biological features of progressive glomerulonephritis (GN), leading to glomerular scarring and dysfunction. Thus, the study of the molecular and cellular mechanisms responsible for pathological glomerular alterations may help to elucidate the pathogenesis of progressive glomerular diseases. A growing body of evidence indicates that beta1 integrin family (beta1 integrins), that mainly mediates cell adhesion to ECM, controls cell behaviors such as cell migration, proliferation, apoptosis and ECM assembly. In addition, a correlation between glomerular expression of beta1 integrins and their ligand ECM components is observed in various human and experimental GN, suggesting that altered beta1 integrins-mediated cell behaviors may contribute to the progression of GN. It is now becoming apparent that the expression of glomerular beta1 integrins is not only critical for maintaining the glomerular capillary permeability but it modulates cell signaling pathways regulating the cell phenotypes involved in the progression of glomerular diseases.

Animals↗

The role of mast cells in acute tubulo-interstitial nephritis with uveitis.

UNLABELLED: We describe the clinicopathological characteristics of two patients with acute tubulo-interstitial nephritis with uveitis (TINU) with mast cells infiltrating the interstitium. The pathogenesis of TINU remains unknown, but a T-cell-mediated immune response was suggested to be involved. Recent studies have shown that infiltrating mast cells are closely associated with the development of renal interstitial fibrosis in glomerulonephritis. To address the role of mast cells in the renal interstitial injury in TINU, immunohistochemical studies were performed in renal biopsy sections using anti-human mast cell tryptase antibody specific for mast cells. In addition, we tried to detect CD68-positive macrophages to compare with the localisation of mast cells within the renal interstitium. Mast cells and macrophages could be detected in renal interstitial lesions of both patients. Massive infiltration of macrophages into interstitial lesions was observed, whereas mast cells were detected in a sporadic rather than a clustered manner, and associated with fibrotic lesions. Repeat renal biopsy findings suggested the involvement of these cells in the renal interstitial injury because the number of infiltrating mast cells and macrophages in the interstitium decreased with the improvements in clinical symptoms and pathological lesions. CONCLUSION: The present study showed that mast cells might play an important role in the development of renal interstitial injury in tubulo-interstitial nephritis with uveitis.

Acute Disease↗

Mean corpuscular volume and the aldehyde dehydrogenase-2 genotype in male Japanese workers.

BACKGROUND: Increased mean corpuscular volume (MCV) is common in alcohol abusers and alcoholics. MCV is higher in Japanese heavy drinkers with inactive aldehyde dehydrogenase-2 (ALDH2) encoded by ALDH2*1/2*2 than among those with active ALDH2 encoded by ALDH2*1/2*1. Inactive ALDH2 dramatically increases blood acetaldehyde levels after alcohol intake. Because moderate and heavy drinkers with ALDH2*1/2*2 have very high risks for esophageal cancer, MCV might serve as an indicator of these high-risk drinkers. METHODS: In this investigation of the association of red cell values with the ALDH2 genotype and possible confounding factors, the drinking, smoking, and dietary habits reported on a structured questionnaire by 163 Japanese working men were subjected to multivariate analyses. RESULTS: Aging, lower body mass index (BMI), more alcohol consumption, and more smoking were positively associated with increased MCV. Among moderate to heavy drinkers (>or=9 units/week; 1 unit = 22 g of ethanol), both MCV and mean corpuscular hemoglobin were higher and the red cell count was lower in those with ADLH2*1/2*2 than in those with ALDH2*1/2*1. Multiple linear regression analysis after adjustment for age, BMI, and smoking revealed that a positive relationship between the amount of drinking and MCV but inverse relationships for drinking and red cell count, as well as hemoglobin and hematocrit values, were significantly stronger for men with ALDH2*1/2*2 than for those with ALDH2*1/2*1, demonstrating a gene-environment interaction. Drinking accounted for 19.9% of interindividual MCV variance among men with ALDH2*1/*2*2 but for only 1.3% of variance among those with ALDH2*1/2*1. Age, BMI, drinking, and smoking accounted for 52.1 and 34.7% of the variation among those with ALDH2*1/2*2 and ALDH2*1/2*1, respectively. Macrocytosis (MCV >or=100.0 fl) was observed in 18 subjects (11.0%), and use of macrocytosis as a biomarker of moderate to heavy drinkers with ALDH2*1/2*2 had a sensitivity of 54.5% (6 of 11) and a specificity of 92.1% (140 of 152). CONCLUSIONS: Alcohol-related red cell value changes associated with inactive ALDH2 in Japanese men suggest the importance of acetaldehyde's role in increasing MCV and the potential for using MCV as a marker for high-risk drinkers for esophageal cancer.

Adult↗

Effects of anti-alpha1 integrin subunit antibody on anti-Thy-1 glomerulonephritis.

alpha1beta1 integrin is a potential collagen-binding extracellular matrix receptor that mediates collagen-dependent cell adhesion, proliferation, migration, and collagen matrix assembly and thereby may participate in the wound healing and pathologic scarring observed in some damaged organs. To clarify the role of alpha1beta1 integrin predominantly expressed on the mesangial cell (MC) surface in nephritic glomeruli, we investigated the involvement of MC-alpha1beta1 integrin in rat anti-Thy-1 glomerulonephritis (GN) by administering function-blocking monoclonal mouse anti-rat alpha1 integrin subunit antibody (anti-alpha1 Ab). Assay of collagen types I and IV mixed gel contraction, an in vitro model of pathologic collagen matrix remodeling, with function-blocking anti-alpha1 Ab and anti-beta1 Ab, revealed that collagen I and IV matrix reorganization is mediated by MC-alpha1beta1 integrin. In addition, conditioned medium from isolated Day 3 anti-Thy-1 nephritic glomeruli showed increased activity of MC-alpha1beta1 integrin-induced mixed collagen gel contraction as compared with that from isolated normal rat glomeruli. Treatment of Day 3 conditioned medium with anti-platelet-derived growth factor-BB antibody significantly inhibited conditioned media-induced gel contraction, whereas treatment with anti-transforming growth factor-beta antibody did not have a significant effect. Rats that received anti-alpha1 Ab from the left renal artery 3 days after anti-Thy-1 GN induction showed significant decreases of glomerular hypercellularity and mesangial matrix accumulation, including collagen I and IV in the left kidney, compared with those rats in which the left kidney received control mouse IgG1. These results suggest that MC-alpha1beta1 integrin is an important extracellular matrix receptor mediating mesangial remodeling characterized by MC proliferation and mesangial matrix reorganization in anti-Thy-1 GN. Platelet-derived growth factor-BB may be involved in early collagen matrix reorganization leading to pathologic mesangial remodeling in this GN model.

Animals↗

Role of mast cell tryptase in renal interstitial fibrosis.

Renal interstitial fibrosis is characterized by increased proliferation of fibroblasts and excessive accumulation of extracellular matrix. Mast cell tryptase has been implicated in the development of tissue fibrosis in skin and lungs. However, the significance of mast cell tryptase in human renal diseases has not been investigated. The potential role of mast cell-derived tryptase in the development of renal fibrosis was studied using immunohistochemical techniques and cultured human renal fibroblast cell lines. Semiquantitative immunostaining analysis of samples from 70 patients with several renal diseases, including IgA glomerulonephritis (GN) (n = 30), non-IgA GN (n = 5), membranous GN (n = 5), focal segmental glomerulosclerosis (n = 4), minor glomerular abnormalities (n = 5), lupus nephritis (n = 3), and acute or chronic tubulointerstitial nephritis (n = 18), revealed that the degree of renal interstitial fibrosis was well correlated with the number of infiltrating tryptase-positive mast cells (P < 0.01). Mast cells could not be detected in damaged glomeruli in any form of renal disease. [(3)H]Thymidine uptake experiments demonstrated that DNA synthesis by cultured renal fibroblasts was increased with the concentration of tryptase (0.5 to 5 nM) coincubated with heparin and was suppressed by coincubation with the protease inhibitors leupeptin and benzamidine hydrochloride. Tryptase alone also increased DNA synthesis by fibroblasts but exhibited less effectiveness, compared with the combination of tryptase and heparin. Conversely, heparin alone suppressed DNA synthesis by fibroblasts. Metabolic [(35)S]methionine-labeling experiments with cultured renal fibroblasts indicated that tryptase increased the synthesis of fibronectin and collagen type I, in a dose-dependent manner. These findings suggest that mast cell tryptase plays a role in the proliferation and extracellular matrix protein production of renal interstitial fibroblasts and thus contributes to the development of renal interstitial fibrosis.

Cell Division↗