Hyung-Cheon Park

We recently demonstrated the use of in vitro expanded kidney-derived mesenchymal stem cells (KMSC) protected peritubular capillary endothelial cells in acute renal ischemia-reperfusion injury. Herein, we isolated and characterized microparticles (MPs) from KMSC. We investigated their in vitro biologic effects on human endothelial cells and in vivo renoprotective effects in acute ischemia-reperfusion renal injury. MPs were isolated from the supernatants of KMSC cultured in anoxic conditions in se

INTRODUCTION: Microparticles (MPs) derived from kidney-derived mesenchymal stem cells (KMSCs) have recently been reported to ameliorate rarefaction of peritubular capillaries (PTC) in ischemic kidneys via delivery of proangiogenic effectors. This study aimed to investigate whether KMSC-derived MPs show anti-fibrotic effects by ameliorating endothelial-to-mesenchymal transition (EndoMT) in human umbilical vein endothelial cells (HUVEC) in vitro and by preserving PTC in kidneys with unilateral ure

BACKGROUND: Transforming growth factor-beta1 (TGF-beta1) is the major profibrotic cytokine involved in many renal diseases, and urinary TGF-beta1 reflects intrarenal TGF-beta1 production. Urinary TGF-beta1 excretion is reported to be significantly increased in patients with immunoglobulin A (IgA) nephropathy. The aim of the present study was to compare the effects of losartan and amlodipine on proteinuria, as well as on serum and urine TGF-beta1 levels in IgA nephropathy patients with hypertensi

Recruitment of various stem and progenitor cells is crucial for the regeneration of an injured organ. Levels of uric acid, one of the prototypical "alarm signals," surge after ischemia-reperfusion injury. Exogenous uric acid rapidly mobilizes endothelial progenitor cells and hematopoietic stem cells and protects the kidney from ischemia. The relatively fast responses to uric acid suggest that preformed second messengers may be released from a storage pool. Here, it is reported that monosodium ur

BACKGROUND: Online haemodiafiltration (OL-HDF) may improve middle molecular clearance in contrast to conventional haemodialysis (HD). However, OL-HDF requires higher convective flows and cannot sufficiently remove large middle molecules. This study evaluated the efficacy of a medium cut-off (MCO) dialyser in removing large middle molecular uraemic toxins and compared it with that of conventional high-flux (HF) dialysers in HD and predilution OL-HDF. METHODS: Six clinically stable HD patients wit

Renal resident stem cells were previously reported within the renal tubules and papillary area. The aim of the present study was to determine whether renal capsules harbor stem cells and whether this pool can be recruited to the renal parenchyma after ischemic injury. We demonstrated the presence of label-retaining cells throughout the renal capsule, at a density of ∼10 cells/mm(2), and their close apposition to the blood vessels. By flow cytometry, in vitro cultured cells derived from the renal

Unilateral ureteral obstruction (UUO), a model of tubulointerstitial scarring (TIS), has a propensity toward regeneration of renal parenchyma after release of obstruction (RUUO). No information exists on the contribution of stem cells to this process. We performed UUO in FVB/N mice, reversed it after 10 days, and examined kidneys 3 wk after RUUO. UUO resulted in attenuation of renal parenchyma. FACS analysis of endothelial progenitor (EPC), mesenchymal stem (MSC) and hematopoietic stem (HSC) cel

Recently, the pathogenic role of uric acid (UA) in both systemic metabolic and atherosclerotic diseases has been investigated. We sought to determine the independent correlation between serum UA levels and coronary artery calcification, as a marker of subclinical atherosclerosis. A total of 4188 individuals without prior coronary artery disease or urate-deposition disease were included. All of the participants underwent multidetector computed tomography (MDCT) for the evaluation of coronary arte

OBJECTIVES: We undertook this study to examine the influence of demographics, peritoneal membrane transport characteristics, nutrition indices, dialysis adequacy, and comorbid diseases on patient survival on continuous ambulatory peritoneal dialysis (CAPD), and to identify whether high peritoneal membrane transport is an independent risk factor for mortality on CAPD. DESIGN: Our retrospective study was carried out in CAPD patients in a large tertiary care teaching hospital. METHODS: Until Decemb

Hyperuricemia is a risk factor for cardiovascular disease and is associated with increased arterial stiffness in high-risk populations. However, given the possible sex-related differences in the prevalence of hyperuricemia, the association between elevated serum uric acid (SUA) level and increased arterial stiffness has yielded conflicting results. We investigated the relationship between SUA and arterial stiffness in asymptomatic healthy subjects who underwent a health examination. Subjects who

The angiotensin-converting enzyme (ACE) gene DD homozygote has been suggested to be a significant risk factor for the progression of diabetic nephropathy. We analyzed clinical parameters and ACE genotype distribution between type 2 diabetic patients at the extremes of renal risk, i.e. an end-stage renal failure (ESRF) group (n = 103, group 1) who were on dialysis therapy due to progression of diabetic nephropathy, and a no progression group (n = 88, group 2) who had maintained normal renal funct

BACKGROUND: Hemodialysis (HD) patients have multiple causes of immune dysfunction and poor immune response to influenza vaccination. We investigated the antibody response rate to a pandemic H1N1/2009 influenza vaccination and clinical parameters influencing the induction of antibody responses in HD patients. METHODS: A total of 114 HD patients were vaccinated with a monovalent adjuvanted H1N1 inactivated influenza vaccine. Titers of neutralizing antibodies were evaluated by hemagglutination inhi

OBJECTIVES: Uremic pruritus is common in patients with chronic kidney disease (CKD). The retention of uremic solutes is thought to be associated with uremic pruritus. Meanwhile, activation of protease-activated receptor-2 (PAR-2) has been suggested to play an important role in pruritus. The present study was performed to investigate the effects of uremic solutes on the expression of PAR-2 in the skin. METHODS: -cresol (PC), and uremic sera from CKD patients were used to stimulate PAR-2 expressio