Biomedical subjects

Chul Woo Yang

Publications and source records attributed to Chul Woo Yang.

At least 19 recordsLinked to original sources

PubMed2007

Downregulation of renal sodium transporters and tonicity-responsive enhancer binding protein by long-term treatment with cyclosporin A.

Tonicity-responsive enhancer binding protein (TonEBP) is a transcriptional activator that is regulated by ambient tonicity. TonEBP protects the renal medulla from the deleterious effects of hyperosmolality and regulates the urinary concentration by stimulating aquaporin-2 and urea transporters. The therapeutic use of cyclosporin A (CsA) is limited by nephrotoxicity that is manifested by reduced GFR, fibrosis, and tubular defects, including reduced urinary concentration. It was reported recently that long-term CsA treatment was associated with decreased renal expression of TonEBP target genes, including aquaporin-2, urea transporter, and aldose reductase. This study tested the hypothesis that long-term CsA treatment reduces the salinity/tonicity of the renal medullary interstitium as a result of inhibition of active sodium transporters, leading to downregulation of TonEBP. CsA treatment for 7 d did not affect TonEBP or renal function. Whereas expression of sodium transporters was altered, the medullary tonicity seemed unchanged. Conversely, 28 d of CsA treatment led to downregulation of TonEBP and overt nephrotoxicity. The downregulation of TonEBP involved reduced expression, cytoplasmic shift, and reduced transcription of its target genes. This was associated with reduced expression of active sodium transporters-sodium/potassium/chloride transporter type 2 (NKCC2), sodium/chloride transporter, and Na(+),K(+)-ATPase-along with increased sodium excretion and reduced urinary concentration. Infusion of vasopressin restored the expression of NKCC2 in the outer medulla as well as the expression and the activity of TonEBP. It is concluded that the downregulation of TonEBP in the setting of long-term CsA administration is secondary to the reduced tonicity of the renal medullary interstitium.

Animals↗

PubMed2006

Differential regulation of B/K protein expression in proximal and distal tubules of rat kidneys with ischemia-reperfusion injury.

Brain/kidney (B/K) protein is a novel double C2-like-domain protein that is highly expressed in rat brain and kidney, but its cellular localization and functional role in the kidney are still undetermined. We examined the cellular localization of B/K protein in the rat kidney under normal and ischemic conditions. Ischemia-reperfusion (I/R) injury was induced by clamping both renal arteries for 45 min, and animals were killed at 1 and 6 h and 1, 2, 3, 5, 7, 14, and 28 days after the reperfusion. Kidney tissues were processed for immunohistochemistry and immunoblot analyses using rabbit anti-B/K polyclonal antibodies. In control kidneys, B/K protein was expressed primarily in distal tubules including the thick ascending limb, distal convoluted and connecting tubules, and collecting duct. Notably, B/K protein was also expressed in the straight portion (S3 segment), but not in the S1 or S2, of proximal tubules, and podocytes of the glomerulus. In rat kidneys with I/R injury, expression of B/K protein was differentially regulated according to the anatomic location. In distal tubules, overall expression of B/K protein was markedly decreased. On the other hand, I/R injury significantly increased B/K protein expression in the S3 segment of the outer medulla as well as in the rat proximal tubular epithelial cell line NRK-52E in vitro. Furthermore, B/K protein was strongly expressed in many exfoliated cells in the lumen and urine. These findings suggest that B/K protein is closely associated with cell death in proximal tubules, which are vulnerable to I/R injury in the kidney.

Animals↗

PubMed2006

Accelerated diabetic nephropathy in mice lacking the peroxisome proliferator-activated receptor alpha.

Peroxisome proliferator-activated receptor (PPAR)alpha, a member of the ligand-activated nuclear receptor superfamily, plays an important role in lipid metabolism and glucose homeostasis and is highly expressed in the kidney. The present studies were aimed at determining the role of PPARalpha in the pathogenesis of diabetic nephropathy using PPARalpha-knockout mice and cultured murine mesangial cells. Diabetes was induced using a low-dose streptozotocin protocol in 8-week-old male 129 SvJ PPARalpha-knockout and wild-type mice. Diabetic PPARalpha-knockout and wild-type mice developed elevated fasting blood glucose (P < 0.001) and HbA1c levels (P < 0.001). Renal functional and histopathological changes in diabetic and nondiabetic PPARalpha-knockout and wild-type mice were evaluated after 16 weeks of hyperglycemia. PPARalpha immunostaining of the cortical tubules of diabetic wild-type mice was elevated by hyperglycemia. In diabetic PPARalpha-knockout mice, renal disease with accompanying albuminuria, glomerular sclerosis, and mesangial area expansion was more severe than in diabetic wild-type mice (P < 0.05) and was accompanied by increased levels of serum free fatty acids and triglycerides (P < 0.01). Furthermore, they exhibited increased renal immunostaining for type IV collagen and osteopontin, which was associated with increased macrophage infiltration and glomerular apoptosis. There were no significant differences in these indexes of renal disease between nondiabetic PPARalpha-knockout and wild-type mice and diabetic PPARalpha wild-type mice. In vitro studies demonstrated that high glucose levels markedly increased the expression of type IV collagen, transforming growth factor-beta1, and the number of leukocytes adherent to cultured mesangial cells. Adherence of leukocytes was inhibited by the PPARalpha agonist fenofibrate. Taken together, PPARalpha deficiency appears to aggravate the severity of diabetic nephropathy through an increase in extracellular matrix formation, inflammation, and circulating free fatty acid and triglyceride concentrations. PPARalpha agonists may serve as useful therapeutic agents for type 1 diabetic nephropathy.

Animals↗

PubMed2006

Hepatic subcapsular steatosis in a diabetic CAPD patient receiving intraperitoneal insulin.

Hepatic subcapsular steatosis is a rare and specific form of fatty change in the liver. It is a unique finding in diabetic patients receiving continuous ambulatory peritoneal dialysis (CAPD) and intraperitoneal insulin treatment. Intraperitoneal administration of insulin causes a unique pattern of fatty infiltration in the subcapsular location of the liver. Here we report a case of hepatic subcapsular steatosis in a diabetic CAPD patient who received intraperitoneal insulin. A 46-year-old diabetic woman on CAPD presented with general weakness. The patient received a total amount of 110 units of regular insulin via intraperitoneal and subcutaneous injection. Her initial blood chemistry showed increased serum lipid and liver enzyme profiles. Abdominal CT scan images and MRI revealed characteristic findings consistent with hepatic subcapsular steatosis. We assumed that the cause was CAPD and concomitant intraperitoneal insulin treatment; therefore, the patient was switched from CAPD to hemodialysis (HD) and began to receive insulin subcutaneously. Two months after the beginning of HD, the hepatic subcapsular steatosis completely resolved.

Diabetes Complications↗

PubMed2005

Inhibitory effect of pravastatin on transforming growth factor beta1-inducible gene h3 expression in a rat model of chronic cyclosporine nephropathy.

BACKGROUND/AIMS: Overexpression of transforming growth factor beta1-inducible gene h3 (betaig-h3) is associated with renal scarring in several models of renal disease. We investigated the inhibitory effect of pravastatin on betaig-h3 expression in a rat model of chronic cyclosporin A (CsA)-induced nephropathy. METHODS: Adult Sprague Dawley rats kept on a low salt diet (0.05% sodium) were treated daily for 4 weeks with vehicle (olive oil, 1 ml/kg), CsA (15 mg/kg) or both CsA and pravastatin (20 mg/kg in drinking water). The effect of pravastatin on betaig-h3 expression was evaluated using in situ hybridization, immunohistochemistry, and immunoblotting. Functional parameters, histopathology (tubulointerstitial fibrosis, TIF, and arteriolopathy), and levels of transforming growth factor beta1 (TGF-beta1) and endothelial nitric oxide synthase were compared for the different treatment groups. RESULTS: Co-administration of pravastatin significantly inhibited betaig-h3 mRNA production and gene expression within the tubulointerstitium of the CsA-treated kidneys, and this paralleled an attenuation of TIF (12.7 +/- 2.2 vs. 35.9 +/- 5.4%, p < 0.01 vs. CsA) and the expression of TGF-beta1 mRNA (279 +/- 40 vs. 719 +/- 85%, p < 0.01 vs. CsA). Pravastatin treatment reduced endothelial nitric oxide synthase protein levels and reversed the renal dysfunction caused by CsA. Neither CsA nor pravastatin affected total serum cholesterol or triglyceride levels in the treatment groups. CONCLUSION: Pravastatin thus effectively abrogated the upregulation of betaig-h3 gene expression and associated TGF-beta1 production, and this was associated with attenuated TIF in this model of chronic CsA-induced nephropathy.

Animals↗

PubMed2005

Effect of FTY720 on chronic cyclosporine nephropathy in rats.

BACKGROUND: Long-term treatment with cyclosporine A (CsA) causes tubulointerstitial inflammation and fibrosis in the kidney. To define the role of lymphocytes in this process, the novel lymphocyte-specific inhibitor FTY720 was administered to rats with experimental model of chronic CsA nephropathy. METHODS: Sprague-Dawley rats were treated daily for 4 weeks with CsA (7.5 mg/kg), or both CsA and FTY720 (0.125 mg/kg). The effects of FTY720 on CsA-induced renal injury were evaluated using renal function tests and histopathology, and the expression of mediators of CsA-induced renal injury (osteopontin, transforming growth factor-beta1 [TGF-beta1], betaig-h3, and angiotensin II). RESULTS: FTY720 treatment significantly decreased T-lymphocyte accumulation in kidneys compared with CsA treatment alone. FTY720 treatment improved not only CsA-induced renal dysfunction but also renal histopathology, demonstrated by decreased macrophage infiltration and interstitial fibrosis. Increased osteopontin, TGF-beta1, betaig-h3, and angiotensin II expression in CsA-treated rat kidneys were decreased with FTY720 treatment. CONCLUSIONS: FTY720 treatment prevents CsA-induced renal injury.

Angiotensin II↗

PubMed2005

Ultrasonographic measurement of intima-media thickness of radial artery in pre-dialysis uraemic patients: comparison with histological examination.

BACKGROUND: Increased intima-media thickness (IMT) of the radial artery is associated with early failure of radiocephalic arteriovenous fistula (AVF) in haemodialysis patients. Therefore, non-invasive measurements of radial artery IMT before AVF operations are very important in predicting AVF patency. This study was designed to evaluate the accuracy of high-resolution ultrasonography in measuring radial artery IMT in pre-dialysis uraemic patients. METHODS: This study enrolled 43 pre-dialysis uraemic patients awaiting radiocephalic AVF operations for the first time. In this study, 17 age- and sex-matched uncomplicated hypertensive patients and 15 healthy subjects were included as a control. We measured the internal diameter (ID) and IMT of the radial artery using high-resolution ultrasonography on the wrists of uraemic patients as well as the control group before the AVF operation. We obtained specimens of the radial artery during the AVF operation and directly measured the IMT by histological examination. RESULTS: The radial artery IMT of the uraemic patients (0.41 +/- 0.09 mm) was significantly thicker, compared to both those of the hypertensive (0.33 +/- 0.05 mm, P < 0.001) and the healthy patients (0.25 +/- 0.04 mm, P = 0.002). In contrast, the radial artery ID in the uraemic patients (1.85 +/- 0.48 mm) was smaller than both that of the hypertensive patients (2.08 +/- 0.31 mm, P = 0.023) and the healthy persons (2.34 +/- 0.37 mm, P = 0.001). Radial artery IMT had a negative correlation with radial artery ID in a total of 73 subjects (r = -0.290, P = 0.012). The value of the radial arterial IMT measured by sonographic examination correlated significantly with that by histological examination in 43 uraemic patients (r = 0.786, P < 0.001) and it correlated significantly with early AVF failure (r = 0.358, P = 0.027). CONCLUSION: Our data suggest that high-resolution ultrasonography is an effective tool in measuring radial artery IMT in uraemic patients before AVF operation.

Adult↗

PubMed2005

Cyclosporine-induced renal injury induces toll-like receptor and maturation of dendritic cells.

BACKGROUND: The toll-like receptor (TLR) is stimulated by not only pathogen-associated molecular patterns but also endogenous TLR ligands provided by injured cells. The influence of cyclosporine A (CsA)-induced renal injury on TLR expression and subsequent signaling pathway was evaluated. METHODS: Induction of chronic CsA nephropathy was made by administering CsA (15 mg/kg/day) for 28 days in rats. The TLR2 and TLR4 mRNA and protein expression, TLR-signaling pathway (MYD88, NF-kappaB and AP-1), putative TLR ligand (heat shock protein 70 [HSP70]), and maturation of dendritic cells were evaluated in CsA-treated rat kidneys. RESULTS: Long-term CsA treatment upregulated TLR2 and TLR4 mRNA and protein expression on renal tubular cells, and these were accompanied by increased MYD88, NF-kappaB and AP-1 expression. Putative TLR ligand (HSP70) was also significantly increased in CsA-treated rat kidney compared with vehicle-treated rat kidney. CsA-treatment increased expression of TNF-alpha mRNA, the number of dendritic cells, and expression of MHC class II antigen. Double-labeling of markers of dendritic cells and MHC class II antigen revealed that matured dendritic cells increased in CsA-treated rat kidney. CONCLUSIONS: CsA-induced renal injury stimulates components of innate immunity, and this finding suggests close association between CsA-induced renal injury and activation of innate immunity.

Animals↗

PubMed2005

Preparation and characterization of biodegradable nanoparticles entrapping immunodominant peptide conjugated with PEG for oral tolerance induction.

PEG-conjugated immunodominant peptides for collagen-induced arthritis (CIA) were prepared for oral tolerance induction instead of whole Type II collagen (CII), because a small peptide can be converted to a macromolecule soluble in methylene chloride by the coupling of poly-ethylene glycol (PEG). PEG-pep1 was synthesized from a peptide and mPEG-NH2 (Mw approximately 5000) using SPDP as a linker, whereas PEG-pep2 was prepared by the direct disulfide coupling between PEG-OD (Mw approximately 10,000) and the peptide. PEG-pep1 and PEG-pep2 were purified by gel permeation chromatography (GPC), and the peak fractions of GPC were identified by GPC and MALDI-TOF mass spectroscopy. The peptide coupling gave much earlier retention times for PEG-pep1 (11.26 min) and PEG-pep2 (10.61 min) than for mPEG-SPDP (15.63 min) and mPEG-OD (14.58 min). The Mw's of mPEG-NH2, mPEG-SPDP, PEG-pep1, mPEG-OD and PEG-pep2 were 5451, 5588, 7035, 10,360 and 11,826, respectively, suggesting that PEG-pep1 and PEG-pep2 of high purity could be obtained. The nanoparticles entrapping PEG-pep1 and PEG-pep2 (NP/PEG-pep1 and NP/PEG-pep2) were prepared by the o/w solvent evaporation method, whereas the peptide-loaded nanoparticles (NP/pep) were prepared by the w/o/w double emulsion method. Although all the nanoparticles had a similar spherical morphology under scanning electron microscopy, NP/pep showed up as having a larger mean size than the others, which was confirmed by dynamic light scattering analysis (NP/pep, 499.7+/-27.2 nm; NP/PEG-pep1, 333.0+/-16.8 nm; NP/PEG-pep2, 342.4+/-15.1 nm). The lower encapsulation efficiency of NP/pep (21.0+/-1.6%) than NP/PEG-pep1 (66.5+/-5.0%) and NP/PEG-pep2 (73.8+/-5.5%) can also be attributed to the preparation method. In in vitro release studies, NP/PEG-pep1 and NP/PEG-pep2 displayed a similar release profile, close to a linear release pattern, whereas NP/pep displayed a tri-phasic release profile. From these results, it was demonstrated that nanoparticles entrapping a PEG-conjugated peptide could be an alternative delivery method for the induction of oral tolerance rather than CII and peptide.

Animals↗

PubMed2005

Combined effects of losartan and pravastatin on interstitial inflammation and fibrosis in chronic cyclosporine-induced nephropathy.

BACKGROUND: Statins and angiotensin II type I receptor blockers have synergistic effects on vascular smooth-muscle-cell proliferation and the progression of renal diseases. We evaluated whether combined treatment with losartan (LSRT) and pravastatin (PRVT) affords superior protection compared with their respective monotherapies in treating chronic cyclosporine (CsA)-induced nephropathy in rats. METHODS: Rats maintained on a low salt diet were given vehicle, CsA (15 mg/kg), CsA and LSRT (10 mg/kg), CsA and PRVT (5 mg/kg), or a combination of CsA, LSRT, and PRVT for 28 days. Basic parameters (renal function, systolic blood pressure, serum high-sensitivity C-reactive protein [hs-CRP], and lipid profiles), histopathology (arteriolopathy, tubulointerstitial fibrosis, and inflammatory cell infiltration), and inflammatory and fibrotic factors (intrarenal CRP, angiotensin II, osteopontin, and transforming growth factor [TGF]-beta1) were studied. RESULTS: LSRT or PRVT treatment significantly attenuated the histopathologic changes induced by CsA, and combined treatment with LSRT and PRVT further decreased these parameters compared with giving each drug alone. Increased levels of angiotensin II, intrarenal CRP, osteopontin, and TGF-beta1 in CsA-treated rat kidney were reduced by treatment with either LSRT or PRVT and were further decreased by the combination of the two drugs. There were no significant differences in systolic blood pressure or serum lipid parameters between groups. CONCLUSIONS: Combined treatment with LSRT and PRVT provided synergistic effects in attenuating inflammatory and fibrotic processes in a rat model of chronic CsA-induced nephropathy, and this effect was independent of their hypolipidemic and hypotensive actions.

Animals↗

PubMed2005

Ischemia-reperfusion injury activates innate immunity in rat kidneys.

BACKGROUND: There is growing evidence of a role of the immune system in the pathophysiology of ischemia-reperfusion (I/R) injury, but the influence of I/R injury on innate immunity is still undetermined. METHODS: Sprague-Dawley rats were used. I/R injury was induced by clamping both renal arteries for 45 min, and the rats were killed 1, 3, 5, and 7 days later. Activation of innate immunity was evaluated in terms of the expression of toll-like receptor (TLR) 2 or TLR4 mRNAs and protein, by the level of the TLR ligand (heat shock protein [HSP] 70), and maturation of dendritic cells by double-label immunohistochemistry of dendritic cells for major histocompatibility complex (MHC) class II antigen. RESULTS: I/R injury increased TLR2 and TLR4 mRNA and protein expression, and they were mainly observed on renal tubular cells. I/R injury also produced endogenous TLR ligand (HSP70) on renal tubular cells. I/R injury increased not only the numbers of dendritic cells but also the production of MHC class II antigen in dendritic cells, suggesting maturation of these cells. Activation of innate immunity was observed at day 1, peaked at days 3 to 5 after I/R injury, and thereafter gradually decreased. CONCLUSIONS: I/R injury rapidly activates the innate immune response.

Animals↗

PubMed2005

Preconditioning with 1,25-dihydroxyvitamin D3 protects against subsequent ischemia-reperfusion injury in the rat kidney.

BACKGROUND/AIM: Induction of heat shock protein 70 (HSP70) is important in the tolerance of subsequent ischemia-reperfusion (I/R) injury. The aim of this study was to evaluate the effect of HSP70 induction by 1,25-dihydroxyvitamin D3 (VD3) on subsequent I/R injury in rats. METHODS: HSP70 was induced in Sprague-Dawley rats by VD3 treatment for 7 days, and the effect of VD3 pretreatment on subsequent I/R injury was evaluated in terms of renal function, tubular necrosis score, tumor necrosis factor alpha mRNA expression, mitogen-activated protein kinase expression, and proliferating cell nuclear antigen expression. RESULTS: VD3 treatment increased HSP70 expression which was localized to renal tubular cells in the outer medulla. Pretreatment with VD3 before I/R injury resulted in (1) decreased blood urea nitrogen and serum creatinine levels; (2) decreased tubular cell necrosis; (3) increased tubular cell proliferation as determined by proliferating cell nuclear antigen expression; (4) decreased tumor necrosis factor alpha mRNA expression, and (5) increased extracellular signal regulated protein kinase and decreased c-Jun N-terminal kinase expression. CONCLUSION: Our study demonstrates that VD3 is a nontoxic inducer of HSP70 and exerts a protective effect against subsequent I/R injury.

Animals↗

PubMed2005

Attenuation of interstitial inflammation and fibrosis by recombinant human erythropoietin in chronic cyclosporine nephropathy.

BACKGROUND: Evidence suggests that recombinant human erythropoietin (rHuEPO) protects neurons and cardiomyocytes from acute insults. We investigated the protective effect of rHuEPO on cyclosporine (CsA)-induced renal injury. METHODS: CsA (15 mg/kg/day) was given to rats for 1 or 4 weeks, and rHuEPO was concurrently administered at a dose of 100 units/kg (thrice weekly). Effects of rHuEPO on CsA-induced renal injury were evaluated with tubulointerstitial fibrosis (TIF) score, macrophage infiltration, expression of proinflammatory and profibrotic cytokines, and apoptotic cell death. RESULTS: Administration of rHuEPO decreased TIF score and the number of macrophages, which increased significantly in CsA-treated rat kidneys. At the molecular level, rHuEPO treatment decreased proinflammatory mediators (osteopontin and C-reactive protein) and profibrotic mediators (transforming growth factor-beta1 and transforming growth factor-beta1-inducible gene-h3). Increased apoptotic cell death in CsA-treated rat kidneys was significantly decreased with rHuEPO cotreatment, and apoptosis-related genes were regulated in favor of cell survival (increased Bcl-2 and suppressed caspase-3). CONCLUSION: rHuEPO has a renoprotective effect against chronic CsA-induced renal injury.

Animals↗

PubMed2005

Protective effect of peroxisome proliferator activated receptor gamma agonists on diabetic and non-diabetic renal diseases.

Peroxisome proliferator activated receptor gamma (PPARgamma) agonist has not only antidiabetic effect but also a protective effect against various types of injury of the kidney. The protective effects of PPARgamma agonists are observed in diabetic nephropathy and non-diabetic renal diseases such as 5/6 ablation model of renal failure, experimental glomerulonephritis, ischemia-reperfusion injury, hypertensive nephropathy and cyclosporin-induced renal injury. The mechanism of renoprotection by PPARgamma agonist is multifactorial. Anti-fibrotic and anti-inflammatory effects, suppression of renin-angiotensin system, vascular protective effect and antiapoptotic effect were proposed.

Animals↗

PubMed2005

Clinical significance of an early protocol biopsy in living-donor renal transplantation: ten-year experience at a single center.

We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation.

Acute Disease↗

PubMed2005

Rosiglitazone protects against cyclosporine-induced pancreatic and renal injury in rats.

Rosiglitazone (RGTZ) has protective effect against various types of injury. This study was performed to evaluate the effect of RGTZ on pancreatic and renal injury caused by cyclosporine (CsA). CsA (15 mg/kg) and RGTZ (3 mg/kg) were administered alone and together to the rats for 28 days. The effect of RGTZ on CsA-induced pancreatic injury was evaluated by intraperitoneal glucose tolerance test (IPGTT), plasma insulin concentrations and pancreatic beta-cell morphology. The effect of RGTZ on CsA-induced renal injury was evaluated by assessing renal function and pathology; mediators of inflammation and fibrosis such as angiotensin II (AngII), osteopontin (OPN) and transforming growth factor-beta1 (TGF-beta1) and apoptotic cell death. Four weeks of CsA treatment caused diabetes, renal dysfunction, typical pathologic lesions (arteriolopathy, interstitial fibrosis and inflammatory cells infiltration) and apoptotic cell death. RGTZ treatment decreased blood glucose concentration, increased plasma insulin concentration and preserved pancreatic beta islet mass. RGTZ treatment improved renal function and histopathology. Pro-inflammatory and pro-fibrotic molecules such as AngII, OPN and TGF-beta1, and apoptotic cell death also decreased with RGTZ treatment. These data suggest that RGTZ has a protective effect against CsA-induced pancreatic and renal injury.

Angiotensin II↗

PubMed2005

Blockade of angiotensin II with losartan attenuates transforming growth factor-beta1 inducible gene-h3 (betaig-h3) expression in a model of chronic cyclosporine nephrotoxicity.

BACKGROUND: We recently demonstrated that upregulation of the transforming growth factor (TGF)-beta1 inducible gene-h3 (betaig-h3) is associated with tubulointerstitial fibrosis (TIF) in a rat model of chronic cyclosporine A (CsA) nephrotoxicity. This study investigated the association between betaig-h3 expression and TIF during losartan treatment in this model. METHODS: Adult Sprague-Dawley rats kept on a salt-depleted diet (0.05% sodium) were treated daily for 4 weeks with vehicle (olive oil, 1 ml/kg), CsA (15 mg/kg) or both CsA and losartan (10 mg/kg in drinking water). The effect of losartan on betaig-h3 expression was evaluated using in situ hybridization, immunohistochemistry and immunoblotting. Histopathology, expressions of TGF-beta1 and intrarenal angiotensin II were compared across treatment groups. RESULTS: Concurrent administration of losartan significantly attenuated betaig-h3 mRNA and protein expression within the tubulointerstitium of CsA-treated kidneys. This was accompanied by the retardation of TIF (18 +/- 5 vs. 39 +/- 5%, p < 0.01 vs. CsA) and the expression of TGF-beta1 mRNA (336 +/- 49 vs. 685 +/- 63%, p < 0.01 vs. CsA) and the number of angiotensin II-positive glomeruli (18 +/- 5 vs. 38 +/- 6, p < 0.05 vs. CsA). CONCLUSION: Losartan is capable of abrogating the upregulation of TGF-beta1 and betaig-h3 expression, and this is associated with attenuated tubulointerstitial fibrosis in chronic CsA nephrotoxicity.

Angiotensin II Type 1 Receptor Blockers↗

PubMed2005

Renal transplantation in a patient with idiopathic thrombocytopenic purpura.

The combination of idiopathic thrombocytopenic purpura (ITP) and chronic renal failure (CRF) is uncommon. This report highlights a case of renal transplantation in a patient with ITP. A 35-year-old man with ITP was admitted with uremic symptoms. A renal transplant and splenectomy was simultaneously performed. A prophylactic pneumococcous vaccination was performed and intravenous immunoglobulin (1 g/kg) was administered before and after the operation. The patient's platelet count increased gradually after the splenectomy. During a two-year follow up period, the graft function was well maintained. Renal transplantation in a patient with ITP is recommended with a well-designed strategy to prevent potential complications.

Adult↗