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I Ebihara

Publications and source records attributed to I Ebihara.

126 records · Page 7Linked to original sources

Changes in concentrations of type IV collagen and tissue inhibitor of metalloproteinase-1 in patients with paraquat poisoning.

Respiratory failure is one of the major causes of death in patients with paraquat poisoning. In paraquat-poisoned lungs, abnormal extracellular matrix regulation occurs. The aim of the present study is to determine whether serum concentrations of type IV collagen and tissue inhibitor of metalloproteinase-1 (TIMP-1) are altered during the course of paraquat poisoning and whether haemoperfusion therapy affects these concentrations. Twenty-one patients were admitted within 3 h after ingestion of paraquat and all patients received direct haemoperfusion therapy. Five out of 21 patients survived and 16 patients died within 28 days. Plasma paraquat concentrations in non-survivors (5740 +/- 380 microg l(-1)) were not significantly different from those in survivors ( 5920 +/- 280 microg l(-1)) before treatment. Haemoperfusion reduced these concentrations in both non-survivors (120 +/- 7 microg l(-1)) as well as survivors (136 +/- 9 microg l(-1)) on day 5. Serum concentrations of type IV collagen and TIMP-1 in survivors showed little change between day 1 (type IV collagen, 90.4 +/- 3.6 ng ml(-1); TIMP-1, 172.2 +/- 7.0 ng ml(-1)) and day 5 (type IV collagen, 92.6 +/- 4.2 ng ml(-1); TIMP-1, 174.2 +/- 7.2 ng ml(-1)). In contrast, these concentrations in non-survivors on day 5 (type IV collagen, 143.6 +/- 7.8 mg ml(-1); TIMP-1, 246.8 +/- 13.6 ng ml(-1)) were significantly higher than those on day 1 (type IV collagen, 88.4 +/- 4.2 ng ml(-1), P < 0.01; TIMP-1, 170.6 +/- 9.2 ng ml(-1), P < 0.05). These data suggest that serum concentrations of type IV collagen and TIMP-1 may be useful indicators for the development of respiratory failure in patients with paraquat poisoning.

Adult↗

Comparative effects of pioglitazone, glibenclamide, and voglibose on urinary endothelin-1 and albumin excretion in diabetes patients.

Urinary endothelin (ET)-1 excretion is present in non-insulin dependent diabetes (NIDDM) patients with microalbuminuria, and an increase in circulating ET-1 precedes the microalbuminuric phase of renal injury related to diabetes. The aim of the present study was to determine whether various drugs alter urinary ET-1 levels and urinary albumin excretion (UAE) in NIDDM patients with microalbuminuria. Forty-five NIDDM patients with microalbuminuria were randomly assigned to three groups: those treated with pioglitazone at 30 mg/day (n=15), those treated with glibenclamide at 5 mg/day (n=15), and those treated with voglibose at 0.6 mg/day (n=15). Patients received these drugs for 3 months. UAE, urinary ET-1, and plasma ET-1 levels were measured in these patients before and after treatment. Before treatment, UAE, urinary ET-1, and plasma ET-1 levels differed little among the three groups. UAE in the 45 NIDDM patients (156.2+/-42.8 microg/min) was greater than that in 30 healthy controls (8.2+/-2.6 microg/min) (P<.001). Urinary ET-1 levels in the NIDDM patients (8.7+/-1.3 ng/g urinary creatinine (UC)) were significantly higher than that in the controls (2.4+/-0.2 ng/g UC) (P<.01). Plasma ET-1 levels, however, in the NIDDM patients (1.3+/-0.4 pg/ml) did not differ significantly from the levels in healthy controls (1.0+/-0.6 pg/ml). Pioglitazone but no glibenclamide or voglibose reduced UAE from 142.8+/-42.2 to 48. 4+/-18.2 microg/min (P<.01) and urinary ET-1 levels from 8.6+/-1.3 to 3.4+/-0.5 ng/g UC (P<.01). These data suggest pioglitazone to be effective in reducing UAE and urinary ET-1 concentrations in NIDDM patients with microalbuminuria.

Albuminuria↗

Elevation of serum levels of metalloproteinase-1, tissue inhibitor of metalloproteinase-1 and type IV collagen, and plasma levels of metalloproteinase-9 in polycystic kidney disease.

Several studies on polycystic kidney disease (PKD) have revealed a number of extracellular matrix (ECM) abnormalities, suggesting that an abnormal ECM plays a role in the development of tubular cysts. Cystic kidney tubules synthesize and secrete high levels of metalloproteinases (MMP), which may participate in the restructuring of the tubular basement membrane. The aim of the present study was to determine whether serum MMP-1, tissue inhibitor of metalloproteinase (TIMP)-1, and type IV collagen levels, and plasma MMP-9 levels were altered in patients with PKD. Sixteen patients with autosomal dominant polycystic kidney disease, and 20 healthy controls were included in this study. Specific enzyme immunoassays were used to measure MMP-1, MMP-9, TIMP-1, and type IV collagen levels. Serum MMP-1 (14.8 +/- 3.6 ng/ml), TIMP-1 (288.6 +/- 48.6 ng/ml), and type IV collagen (192.6 +/- 38.8 ng/ml) concentrations, and plasma MMP-9 (90.2 +/- 26.8 ng/ml) concentrations in patients with PKD were significantly higher than those in healthy controls (MMP-1; 6.6 +/- 0.9 ng/ml, p < 0.01, MMP-9; 36.4 +/- 12.2 ng/ml, p < 0.01, TIMP-1; 164.6 +/- 22.8 ng/ml, p < 0.01, and type IV collagen; 86.6 +/- 14.2 ng/ml, p < 0.001). The present results suggest that ECM abnormalities associated with cystic kidney may result from aberrant degradation as well as from abnormal synthesis of ECM components.

Collagen↗

The urinary podocyte as a marker for the differential diagnosis of idiopathic focal glomerulosclerosis and minimal-change nephrotic syndrome.

BACKGROUND/AIMS: Detection of podocytes in the urine sediment of children indicates that severe podocyte injury occurred in the glomerulus. Focal glomerulosclerosis (FGS) and minimal-change nephrotic syndrome (MCNS) are kidney diseases characterized by massive proteinuria. The aim of the present study was to determine whether urinary podocytes can be detected in patients with idiopathic FGS or MCNS and whether immunosuppression therapy alters these cells. METHODS: Twenty patients with MCNS (nephrotic stage, n = 12; remission stage, n = 8), 15 patients with FGS and 20 healthy controls were included in the present study. Urinary podocytes were stained by immunofluorescence. All patients with MCNS at the nephrotic stage received prednisolone for 6 months, and all patients with FGS received some form of immunosuppression therapy including prednisolone, cyclophosphamide or mizoribine for 12 months. RESULTS: The 12 nephrotic-stage MCNS patients achieved remission after treatment. Seven of the 15 FGS patients also achieved remission, but the other 8 remained in the nephrotic stage. Urinary podocytes were not detected in any patient with MCNS nor were they detected in healthy controls. Urinary podocytes were detected in all FGS patients (mean, 4.2 cells/ml) before treatment and the number of cells decreased in the 7 patients who achieved remission. The number of podocytes was unchanged in the other 8 patients even after treatment. CONCLUSION: Urinary podocytes may be a useful diagnostic indicator for differentiation between FGS and MCNS. These cells may also mark disease progression in cases of FGS.

Adult↗

Effects of angiotensin-converting enzyme inhibitor, angiotensin II receptor antagonist and calcium antagonist on urinary podocytes in patients with IgA nephropathy.

The urinary podocyte is postulated to be a marker for estimation of the severity of active glomerular injury and a predictor of disease progression in children with glomerulonephritis. Non-dihydropyridine calcium antagonist, including verapamil, reduce proteinuria to an extent similar to that of the angiotensin-converting enzyme inhibitor (ACEI), including trandolapril, but to a greater extent than other antihypertensives. Angiotensin (Ang) II receptor antagonists, including candesartan cilexetil, show potent and long-term preventive effects against the progression of renal injury. The aim of the present study is to assess whether verapamil, trandolapril and candesartan cilexetil affect proteinuria and urinary podocytes in patients with IgA nephropathy. Thirty-two normotensive patients aged 18-54 years with biopsy-proven IgA nephropathy, nonnephrotic proteinuria (1-3 g/day), and normal renal function (creatinine clearance >80 ml/min) were studied. Twenty patients with diffuse mesangial proliferative glomerulonephritis (non-IgA PGN) and 20 healthy controls were also included in this study. The number of urinary podocytes in patients with advanced IgA nephropathy (n = 16) was significantly higher than that in patients with the disease in the mild stage (n = 16) (p < 0.01) or in patients with non-IgA PGN (p < 0.01). Urinary podocytes were not detected in healthy controls. The 32 patients with IgA nephropathy were randomly divided into four treatment groups: those treated with verapamil (120 mg/day, n = 8); those treated with trandolapril (2 mg/day, n = 8); those treated with candesartan cilexetil (8 mg/day, n = 8), and those given a placebo (n = 8). Treatment continued for 3 months. Antiproteinuric response in the trandolapril group was similar to that in the candesartan cilexetil group (-38 vs. -40%). The action of trandolapril or candesartan cilexetil was greater than that of verapamil (p < 0.01). Reduction in the number of urinary podocytes from baseline was significantly greater in patients treated with trandolapril or candesartan cilexetil than in patients treated with verapamil (p < 0.01). However, there was no difference between patients treated with trandolapril and those treated with candesartan cilexetil. Proteinuria and urinary podocytes were unaffected in the placebo group. These data suggest that urinary podocytes may be a marker of disease activity in adult patients with IgA nephropathy and that trandolapril and candesartan cilexetil are more effective than verapamil in reducing the number of podocytes.

Adult↗

Effect of methylprednisolone on transforming growth factor-beta, insulin-like growth factor-I, and basic fibroblast growth factor gene expression in the kidneys of NZB/W F1 mice.

The present study was carried out to determine whether transforming growth factor-beta, insulin-like growth factor-I and basic fibroblast growth factor mRNA levels were correlated with disease activity in NZB/W F1 mice, an animal model of systemic lupus erythematosus. Levels of mRNA for these three growth factors increased significantly as nephritis progressed in these mice. At 48 weeks of age, transforming growth factor-beta, insulin-like growth factor-I, and basic fibroblast growth factor mRNA levels showed a 11- (p < 0.001), 10- (p < 0.001), and 8-fold (p < 0.001) increase, respectively, in the renal cortex of NZB/W F1 mice when compared with NZW control mice. In NZW kidneys, these mRNA levels showed little change throughout the study period. At 24 weeks of age, NZB/W F1 mice were divided in 2 groups that received either methylprednisolone or saline injections for 24 weeks. The development of histological lesions and the increase in these growth factor mRNA levels in the kidneys of NZB/W F1 mice were both suppressed by methylprednisolone. These results indicate that the transforming growth factor-beta, insulin-like growth factor and basic fibroblast growth factor may play a role in the progression of murine lupus nephritis and that methylprednisolone may be an effective treatment at the transcription level of these growth factor genes for this type of nephritis.

Animals↗

Renal expression of mRNAs for endothelin-1, endothelin-3 and endothelin receptors in NZB/W F1 mice.

Endothelin (ET)-1, ET-3, and ET receptors are widely distributed in the vascular system and the kidney. The present study was designed to measure the renal concentrations of ET-1, ET-3, and ET receptor mRNAs in NZB/W F1 mice at 8, 24, and 48 weeks of age. The renal concentration of ET-1 mRNA increased significantly in NZB/W F1 mice as their nephritis progressed, reaching, by 48 weeks, a 10-fold higher concentration than in control NZW mice. Renal ET-3 mRNA concentrations, however, remained unchanged. The renal concentrations of ET receptor A and B mRNAs in NZB/W F1 mice increased gradually with the progression of nephritis, reaching 5- and 3-fold higher concentrations, respectively, at 48 weeks of age than found in control mice. Transforming growth factor-beta (TGF-beta) and tumor necrosis factor-alpha (TNF-alpha) have been shown to stimulate ET-1 mRNA expression in cultured mesangial cells. We therefore also examined the concentrations of TGF-beta and TNF-alpha mRNAs in the renal tissues of NZB/W F1 mice, and found that, at 48 weeks of age, they were 10- and 8-fold higher, respectively, than in control NZW mice. At 24 weeks, NZB/W F1 mice were divided into two groups receiving either methylprednisolone (MPSL) or saline injections for the following 24 weeks. The development of the histologic lesions characteristic of lupus nephritis and the increased renal concentrations of ET-1, ET receptors, TGF-beta and TNF-alpha mRNAs were suppressed by MPSL treatment. These data suggest that ET and ET receptor gene transcription is upregulated in the renal tissues of NZB/W F1 mice and that the beneficial treatment of lupus nephritis with MPSL is accompanied by a reduction in the elevated concentrations of ET-1, ET receptors, TGF-beta and TNF-alpha mRNAs.

Aging↗

Abnormal gene expression of matrix metalloproteinases and their inhibitor in glomeruli from diabetic rats.

The steady state levels of mRNA encoding for metalloproteinase (MMP)-1, -2, -3, and -9 and tissue inhibitor of metalloproteinase (TIMP)-1 were examined in glomeruli at 4, 12, and 24 weeks after the injection of streptozocin (STZ) in rats. The mRNA levels for MMP-1 and MMP-3 decreased with age in STZ-induced diabetes. At 24 weeks after STZ injection, mRNA levels for MMP-1 and MMP-3 fell to 40% (p < 0.01) and 20% (p < 0.01), respectively, in the glomeruli of diabetic rats when compared with control rats. In contrast, mRNA levels for TIMP-1 increased significantly with age in the diabetic glomeruli and reached an 8-fold (p < 0.01) increased at 24 weeks after STZ injection. mRNA levels for MMP-2 were not altered in glomeruli from diabetic and control rats throughout the experimental period, whereas those for MMP-9 were not detected in glomeruli from either group of rats. Insulin treatment partially ameliorated the decrease in mRNA levels for MMP-1 and MMP-3 and the increase in those for TIMP-1 in the glomeruli of diabetic rats. These data indicate that abnormal gene regulation of MMPs and TIMP-1 in the glomeruli of diabetic rats may contribute to the progression of glomerular lesions and that hyperglycemia or insulin deficiency may be associated with abnormal MMPs and TIMP-1 gene regulation.

Animals↗

Altered extracellular matrix component gene expression in murine polycystic kidney.

The DBA/2FG-pcy mouse has a form of slowly progressive kidney disease that appears similar in many respects to that seen in the autosomal dominant form of human polycystic kidney disease. This study was designed to assess how the expression of extracellular matrix component genes is regulated in a model of murine polycystic kidney disease and control DBA/2 mice at 8, 16, and 30 weeks of age. The mRNA levels encoding for collagen IV, the B1 and B2 chains of laminin, heparan sulfate proteoglycan, fibronectin, and collagens I and III increased with the progression of cystic lesions in the kidney of DBA/2FG-pcy mice. At 30 weeks of age, mRNA levels for collagen IV, laminin B1 and B2, heparan sulfate proteoglycan, fibronectin, and collagens I and III were increased 8.1-fold, 7.0-fold, 7.0-fold, 9.8-fold, 7.0-fold, 5.5-fold, and 5.4-fold, respectively, compared to those of control DBA/2 mice. An immunofluorescence study revealed the irregular staining for collagen IV, laminin, heparan sulfate proteoglycan, and collagens I and III around the cysts. These data suggest that changes in the expression of basement membrane components and interstitial collagens are associated with the development of polycystic kidney disease.

Animals↗

Effects of enalapril treatment on gene expression of smooth muscle myosin heavy chain isoforms in glomeruli of diabetic rats.

We have previously shown that smooth muscle contains three types of myosin heavy chains: SM1, SM2, and SMemb. The present study was designed to assess how glomerular expression of mRNA for these isoforms is regulated and whether their expression is affected by enalapril treatment in diabetic rats. Animals were divided into 4 groups: (1) untreated diabetic rats; (2) enalapril-treated diabetic rats; (3) untreated control rats, and (4) enalapril-treated control rats. Enalapril treatment was continued for 24 weeks. The glomerular mRNA levels for SM1 and SM2 showed little change in all groups throughout the experimental period. In contrast, SMemb mRNA in group 1 increased significantly with age compared to levels found in untreated controls (4.6-fold higher at 4 weeks, p < 0.01; 6.8-fold higher at 12 weeks, p < 0.01, and 10.6-fold higher at 24 weeks, p < 0.001). Enalapril reduced both creatinine clearance (p < 0.01) and urinary protein excretion (p < 0.01) in diabetic rats. Moreover, enalapril significantly attenuated the increase in the glomerular SMemb mRNA level in diabetic rats (the difference between treated and untreated rats was significant at p < 0.01 from week 4 to 24). However, enalapril had no effect on SMemb mRNA levels in controls. These data suggest that SMemb is a molecular marker for phenotypic alteration and that the beneficial effect of enalapril on proteinuria and renal function may be, at least in part, associated with reducing SMemb mRNA expression in diabetic glomeruli.

Angiotensin-Converting Enzyme Inhibitors↗

In situ hybridization of type I collagen mRNA in puromycin aminonucleoside-induced glomerulosclerosis.

In puromycin aminonucleoside (PAN)-induced focal glomerulosclerosis (FGS), the accumulation of type I collagen has been reported to be observed immunohistochemically in the sclerotic area. The present study was designed to identify the cell type involved in the synthesis of type I collagen in glomerulosclerosis. Tissue sections obtained from rat kidneys with PAN-induced FGS were hybridized with digoxigenin-labeled alpha 1(I) collagen anti-sense and sense cRNA probes. Hybridization signals of alpha 1(I) collagen mRNA were mainly detected in adhesive lesions on the glomerular capillary loop, suggesting that alpha 1(I) collagen mRNA-positive cells were visceral or parietal epithelial cells and did not have a mesangial distribution. Signals were also detected in interstitial cells. The alpha 1(I) collagen mRNA expression, however, was not observed in ED-1-positive cells. It is likely that intrinsic glomerular cells and interstitial cells, but not macrophages, synthesize type I collagen in sclerotic glomeruli.

Animals↗

Transcriptional activation of matrix genes by transforming growth factor beta 1 in mesangial cells.

The accumulation of mesangial matrix is a common histologic abnormality observed over the course of various glomerular diseases. To examine the role of transforming growth factor beta 1 (TGF-beta 1), a well-known regulator of extracellular matrix metabolism, in such processes, we studied the effects of this peptide on the gene expression of extracellular matrix components in cultured rat mesangial cells. TGF-beta 1 increased the mRNA levels for alpha 1 (I) and alpha 1 (IV) collagens and fibronectin. The increase in these mRNA levels was detectable 6 h after stimulation by TGF-beta 1. At 24 h, the mRNA levels for alpha 1 (I) and alpha 1 (IV) collagens and fibronectin increased 1.9-, 2.8- and 2.6-fold, respectively, above their basal levels. Concomitant treatment with cycloheximide did not prevent the stimulation by TGF-beta 1 and resulted in exceptional superinduction for the fibronectin gene. Concomitant treatment with actinomycin D completely inhibited the increase in the mRNA levels induced by TGF-beta 1. Furthermore, TGF-beta 1 showed no stabilizing effect on the transcripts. These results suggest that TGF-beta 1, which is released in glomerular injury, induces an increase in the transcription of the alpha 1 (I) and alpha 1 (IV) collagen and fibronectin genes in mesangial cells and may mediate the accumulation of the extracellular matrix in the mesangium.

Animals↗

Increased endothelin-1 mRNA expression in peripheral blood monocytes of dialysis patients.

OBJECTIVE: To compare plasma endothelin (ET)-1 level and ET-1 mRNA level in peripheral blood monocytes of patients undergoing hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD). DESIGN: Endothelin-1 mRNA level in peripheral blood monocytes and plasma ET-1 level were studied in 30 HD patients, 15 CAPD patients, 20 chronic renal failure patients not being dialyzed, and 20 normal healthy controls. Hemodialysis patients were dialyzed three times per week with a bicarbonate dialysate. Different types of dialyzer membrane, viz., cellulose triacetate, cuprophane, polysulfone, polyacrylonitrile, and ethylenevinylalcohol were used in 8, 6, 6, 5, and 5 patients, respectively. Continuous ambulatory peritoneal dialysis patients were dialyzed with four daily exchanges of a 2-L dialysate containing glucose at a concentration of 1.5% to 2.5%. RESULTS: Higher levels of ET-1 mRNA in monocytes were observed in HD patients than in CAPD patients (p < 0.01), chronic renal failure patients (p < 0.01), or normal healthy controls (p < 0.001). The level of ET-1 mRNA in monocytes at the end of HD was not significantly higher than that at the start of HD. In addition, these mRNA levels in HD patients showed little difference with different types of dialysis membrane. Plasma ET-1 level in HD patients (10.2 +/- 2.4 pg/mL) was also higher than that in CAPD patients (7.8 +/- 1.6 pg/mL, p < 0.01), in chronic renal failure patients (4.8 +/- 1.2 pg/mL, p < 0.01), or in normal controls (2.6 +/- 0.8 pg/mL, p < 0.001). CONCLUSION: Dialysis itself did not significantly affect ET-1 mRNA levels in monocytes. Chronic stimulation of peripheral blood monocytes may be associated with higher levels of ET-1 mRNA and plasma ET-1 in HD patients than in CAPD patients.

Adult↗