Search

Background: Angiotensin II induces glomerular and podocyte injury via systemic and local vasoconstrictive or non-hemodynamic effects including oxidative stress. The release of reactive oxygen species (ROS) from podocytes may participate in the development of glomerular injury and proteinuria. We studied the role of oxidative stress in angiotensin II-induced podocyte apoptosis.Methods: Mouse podocytes were incubated in media containing various concentrations of angiotensin II at different incubation times and were transfected with NADH/NADPH oxidase 4 (Nox4) or angiotensin II type 1 receptor for 24 hours. The changes in intracellular and mitochondrial ROS production and podocyte apoptosis were measured according to the presence of angiotensin II.Results: Angiotensin II increased the generation of mitochondrial superoxide anions and ROS levels but suppressed superoxide dismutase activity in a dose- and time-dependent manner that was reversed by probucol, an antioxidant. Angiotensin II increased Nox4 protein and expression by a transcriptional mechanism that was also reversed by probucol. In addition, the suppression of Nox4 by small interfering RNA (siRNA) reduced the oxidative stress induced by angiotensin II. Angiotensin II treatment also upregulated AT1R protein. Furthermore, angiotensin II promoted podocyte apoptosis, which was reduced significantly by probucol and Nox4 siRNA and also recovered by angiotensin II type 1 receptor siRNA.Conclusion: Our findings suggest that angiotensin II increases the generation of mitochondrial superoxide anions and ROS levels via the upregulation of Nox4 and angiotensin II type 1 receptor. This can be prevented by Nox4 inhibition and/or antagonizing angiotensin II type 1 receptor as well as use of antioxidants.

Propofol is widely used to sedate agitated patients in intensive care units. However, it can cause a rare but fatal complication, propofol-related infusion syndrome (PRIS). The pathophysiology of PRIS is not clear, and there is no definitive diagnosis and treatment. We report a successfully treated case of PRIS in a critically ill patient receiving low-dose propofol infusion. A 59-year-old male patient complaining of sudden chest pain repeatedly collapsed in an ambulance and the emergency room, and veno-arterial extracorporeal membrane oxygenation was delivered. He was diagnosed with a total occluded left anterior descending coronary artery in coronary angiography. On day 20, he showed arrhythmia, increased creatinine kinase (CK), and increased CK-MB and troponin I, accompanied by unstable hemodynamic status despite high-dose vasopressors. He was administered propofol for 20 days at an average dose of 1.3 mg/kg/hr owing to issues with agitation and ventilator synchrony. We strongly suspected PRIS and immediately discontinued propofol infusion, and he was successfully treated with aggressive supportive care. PRIS can occur in patients administered propofol for a prolonged period at low doses. Thus, clinicians should use propofol with caution for PRIS and change to alternative sedatives for long-term sedation.

BACKGROUND AND AIMS Oxidative stress induced by non-hemodynamic effects of angiotensin II in podocytes participates in the development of glomerular injury and proteinuria. We studied the pathophysiologic roles of oxidative stress in angiotensin II-induced podocyte apoptosis. METHOD Mouse podocytes were incubated in media containing various concentrations of angiotensin II at different incubation times and transfected by Nox4 or AT1R siRNAs or negative control scrambled siRNA for 24 h. The changes of podocyte oxidative stress and apoptosis were observed by confocal imaging, western blotting, real-time PCR, FACS and TUNEL assays according to the presence of angiotensin II. RESULTS Angiotensin II increased the generation of mitochondrial superoxide anions and reactive oxygen species levels but suppressed superoxide dismutase activity that was reversed by probucol, an antioxidant. Angiotensin II also increased NADH/NADPH oxidase 4 protein and expression in a transcriptional mechanism that was also reversed by probucol. In addition, the suppression of NADH/NADPH oxidase 4 by siRNA reduced the oxidative stress induced by angiotensin II. Furthermore, angiotensin II promoted podocyte apoptosis that was reduced significantly by probucol and NADH/NADPH oxidase 4 siRNA, and also recovered by angiotensin II type 1 receptor siRNA. In sum, angiotensin II induced podocyte oxidative stress and apoptosis through NADH/NADPH oxidase 4 and angiotensin II type 1 receptor. CONCLUSION These findings suggest that angiotensin II promotes podocyte mitochondrial oxidative stress, resulting in apoptosis via the upregulation of NADH/NADPH oxidase 4 and angiotensin II type 1 receptor, which could be prevented by NADH/NADPH oxidase 4 inhibition and/or antagonizing angiotensin II type 1 receptor as well as antioxidants.

Background/aims Angiotensin II (Ang II) induces podocyte injury resulting in apoptosis in vitro and in vivo. However, the relationship between autophagy and apoptosis in Ang II-induced podocyte injury is unknown and the role of Ang II-induced autophagy in podocyte survival or death remains unclear. We investigated the sequential relationship between autophagy and apoptosis in Ang II-induced podocytes as well as the role of phosphatidylinositide 3-kinase (PI3-kinase). Methods Mouse podocytes were incubated in media containing various concentrations of Ang II and at different incubation times. The changes of podocyte autophagy and apoptosis were observed by electron microscopy, confocal imaging, western blotting, and FACS assay according to the presence of Ang II. Results Ang II enhanced the podocyte expression of the autophagic proteins, LC3A/B-II and beclin-1, and also increased the number of autophagosomes compared with control cells at early phase of 12 hours in a dose-dependent manner. This effect was inhibited by pretreatment with 3-methyladenine (3-MA), a PI3-kinase class III inhibitor. Thereafter, the Ang II-induced enhancement in autophagy decreased, whereas, podocyte apoptosis appeared later at 24 hours in concentration- and time-dependent manners in FACS and TUNEL assays. 3-MA and LY294002, a pan PI3-kinase inhibitor, further increased Ang II-induced podocyte apoptosis. Suppression of autophagy by Atg5 siRNA could induce podocyte apoptosis and further augment high-dose Ang II-induced podocyte apoptosis. Conclusion These findings suggest that Ang II promotes autophagy in podocytes before apoptosis as an early adaptive cytoprotective mechanism for podocyte survival after Ang II treatment, and the transitional imbalance between autophagy and apoptosis causes podocyte injury.

Propofol is widely used to sedate agitated patients in intensive care units. However, it can cause a rare but fatal complication, propofol-related infusion syndrome (PRIS). The pathophysiology of PRIS is not clear, and there is no definitive diagnosis and treatment. We report a successfully treated case of PRIS in a critically ill patient receiving low-dose propofol infusion. A 59-year-old male patient complaining of sudden chest pain repeatedly collapsed in an ambulance and the emergency room, and veno-arterial extracorporeal membrane oxygenation was delivered. He was diagnosed with a total occluded left anterior descending coronary artery in coronary angiography. On day 20, he showed arrhythmia, increased creatinine kinase (CK), and increased CK-MB and troponin I, accompanied by unstable hemodynamic status despite high-dose vasopressors. He was administered propofol for 20 days at an average dose of 1.3 mg/kg/hr owing to issues with agitation and ventilator synchrony. We strongly suspected PRIS and immediately discontinued propofol infusion, and he was successfully treated with aggressive supportive care. PRIS can occur in patients administered propofol for a prolonged period at low doses. Thus, clinicians should use propofol with caution for PRIS and change to alternative sedatives for long-term sedation.

CD2-associated protein (CD2AP), an adaptor protein, plays several important roles in podocyte function, linking slit diaphragms to actin-based cytoskeleton and sending survival signals. Here, we investigated whether ginseng total saponin (GTS) had a protective role in the changes of podocyte CD2AP protein and podocyte apoptosis under in vitro diabetic conditions. Conditionally immortalized mouse podocytes cultured with normal glucose (5 mM) or high glucose (30 mM) and with or without advanced glycosylation end products were treated with GTS. We found that CD2AP co-localized with the F-actin fibers in podocyte cytoplasm using confocal imaging; however, diabetic conditions caused the podocytes to diminish and conglomerate CD2AP stainings in the peripheral cytoplasm, which were recovered by GTS. Diabetic conditions also suppressed CD2AP protein levels at 6 and 24 h in western blotting. These phenotypical changes of CD2AP protein were mitigated by GTS. Diabetic conditions also induced podocyte apoptosis at 24 h, which were attenuated by GTS. These findings provide a novel mechanism that diabetic conditions induce quantitative and qualitative changes of podocyte CD2AP protein and apoptosis, which would be restored by GTS.

To understand the genetics of steroid-sensitive nephrotic syndrome (SSNS), we conducted a genome-wide association study in 987 childhood SSNS patients and 3,206 healthy controls with Japanese ancestry. Beyond known associations in the HLA-DR/DQ region, common variants in NPHS1-KIRREL2 (rs56117924, P=4.94E-20, odds ratio (OR) =1.90) and TNFSF15 (rs6478109, P=2.54E-8, OR=0.72) regions achieved genome-wide significance and were replicated in Korean, South Asian and African populations. Trans-ethnic meta-analyses including Japanese, Korean, South Asian, African, European, Hispanic and Maghrebian populations confirmed the significant associations of variants in NPHS1-KIRREL2 (P(meta)=6.71E-28, OR=1.88) and TNFSF15 (P(meta)=5.40E-11, OR=1.33) loci. Analysis of the NPHS1 risk alleles with glomerular NPHS1 mRNA expression from the same person revealed allele specific expression with significantly lower expression of the transcript derived from the risk haplotype (Wilcox test p=9.3E-4). Because rare pathogenic variants in NPHS1 cause congenital nephrotic syndrome of the Finnish type (CNSF), the present study provides further evidence that variation along the allele frequency spectrum in the same gene can cause or contribute to both a rare monogenic disease (CNSF) and a more complex, polygenic disease (SSNS).

Background: The objective of this study was to investigate the characteristics and clinical outcomes of critically ill cancer patients admitted to intensive care units (ICUs) in Korea. Methods: This was a retrospective cohort study that analyzed prospective collected data from the Validation of Simplified Acute Physiology Score 3 (SAPS3) in Korean ICU (VSKI) study, which is a nationwide, multicenter, and prospective study that considered 5,063 pa tients from 22 ICUs in Korea over a period of 7 months. Among them, patients older than 18 years of age who were diagnosed with solid or hematologic malignancies prior to admission to the ICU were included in the present study. Results: During the study period, a total of 1,762 cancer patients were admitted to the ICUs and 833 of them were deemed eligible for analysis. Six hundred fifty-eight (79%) had solid tumors and 175 (21%) had hematologic malignancies, respectively. Respiratory problems (30.1%) was the most common reason leading to ICU admission. Patients with hematologic malignancies had higher Sequential Organ Failure Assessment (12 vs. 8, P

Advances in podocytology and genetic techniques have expanded our understanding of the pathogenesis of hereditary steroid-resistant nephrotic syndrome (SRNS). In the past 20 years, over 45 genetic mutations have been identified in patients with hereditary SRNS. Genetic mutations on structural and functional molecules in podocytes can lead to serious injury in the podocytes themselves and in adjacent structures, causing sclerotic lesions such as focal segmental glomerulosclerosis or diffuse mesangial sclerosis. This paper provides an update on the current knowledge of podocyte genes involved in the development of hereditary nephrotic syndrome and, thereby, reviews genotype-phenotype correlations to propose an approach for appropriate mutational screening based on clinical aspects.

Angiotensin II (Ang II) works as a paracrine or autocrine cytokine agent to regulate renal functions and promotes podocytes dysfunction directly or indirectly, causing proteinuria. The glomerular slit diaphragm (SD) serves as a size-selective barrier and is linked to the actin-based cytoskeleton by adaptor proteins, including CD2-associated protein (CD2AP). Therefore, damages to CD2AP affect not only the function of the SD, but also directly disrupt the podocyte cytoskeleton, leading to proteinuria. In addition, CD2AP can facilitate the nephrin-induced phosphoinositide 3-kinase (PI3-K)/Akt signaling, which protects podocytes from apoptosis. Here we found that CD2AP staining was located diffusely but predominantly in the peripheral cytoplasm and CD2AP co-localized with nephrin in mouse podocytes; however, Ang II decreased CD2AP staining diffusely and induced a separation from concentrated nephrin. Ang II notably reduced CD2AP expression in time- and concentration-dependent manners, and this was significantly recovered by losartan. Ang II induced podocyte apoptosis in time- and concentration-dependent manners in TUNEL and FACS assays. LY294002, a PI3-K inhibitor, further reduced CD2AP expression and increased podocyte apoptosis, which was augmented by siRNA for CD2AP. Thus, Ang II induces the relocalization and reduction of CD2AP via AT1R, which would cause podocyte apoptosis by the suppression of CD2AP/PI3-K signaling.

Aim Extracorporeal cardiopulmonary resuscitation (ECPR) has been shown to have survival benefit in patients who had in-hospital cardiac arrest (IHCA). However, limited data are available on the role of extracorporeal membrane oxygenation (ECMO) for out-of-hospital cardiac arrest (OHCA). Therefore, we aimed to investigate clinical outcomes and predictors of in-hospital mortality in patients who had OHCA and who underwent ECPR. Methods From January 2004 to December 2013, 235 patients who received ECPR were enrolled in a retrospective, single-centre, observational registry. Among those, we studied 35 adult patients who had OHCA. The primary outcome was in-hospital mortality. Results Among 35 patients with a median age of 55 years (IQR 45–64), 29 (82.9%) of whom were male, ECMO implantation was successful in all and 10 patients (28.6%) lived to be discharged from the hospital. In 18 cases (51.4%), first monitored rhythms were identified as ventricular tachycardia/ventricular fibrillation, that is, shockable rhythm. There were no differences between in-hospital survivors and non-survivors regarding median time of arrest to cardiopulmonary resuscitation (CPR) (survivors: 23.5 min (IQR 18.8–27.3) vs non-survivors: 20.0 min (IQR 15.0–24.5); p=0.41) and median time of CPR to ECMO pump-on (survivors: 61.0 min (IQR 39.8–77.8) vs non-survivors 50.0 min (IQR 44.0–72.5); p=0.50). In 23 cases (65.7%), ischaemic heart disease was diagnosed and successful revascularisation was achieved in a significantly higher proportion of the survivor group (8/10 (80.0%)) than the non-survivor group (8/25 (32.0%)) (p=0.02). Witnessed arrest (HR=3.96; 95% CI 1.38 to 11.41; p=0.01), bystander CPR (HR=4.05; 95% CI 1.56 to 10.42; p=0.004) and successful revascularisation (HR=2.90; 95% CI 1.23 to 6.86; p=0.02) were independent predictors of survival-to-discharge in patients who had OHCA in univariate Cox regression analysis. Conclusion Survival rate for ECPR in the setting of OHCA remains poor. Our findings suggest that ECMO implantation should be very carefully considered in highly selected patients who had OHCA with little no-flow time and a reversible cause.

Puromycin aminonucleoside (PAN)-induced nephrosis is a widely studied animal model of human idiopathic nephrotic syndrome because PAN injection into rats results in increased glomerular permeability with the characteristic ultrastructural changes in podocytes similar to human nephrosis. To investigate the role of zonula occludens (ZO)-1 and oxidative stress on PAN-induced podocyte phenotypical changes and hyperpermeability in vitro, we cultured rat and mouse podocytes and treated with various concentrations of PAN. PAN treatment increased oxidative stress level of podocytes significantly with the induction of Nox4. In addition, PAN changed the ultrastructure of podocytes, such as shortening and fusion of microvilli, and the separation of intercellular gaps, which were improved by anti-oxidative vitamin C and Nox4 siRNA. PAN also disrupted the intercellular linear ZO-1 staining and induced inner cytoplasmic re-localization of ZO-1 protein, resulting in increased podocyte intercellular permeability. PAN reduced ZO-1 protein amount and mRNA expression in a dose-dependent manner, which means that PAN could also modulate ZO-1 protein transcriptionally. However, the decreased ZO-1 protein of podocytes by PAN was improved by Nox4 siRNA transfection. Furthermore, vitamin C mitigated the quantitative and distributional disturbances of ZO-1 protein caused by PAN. Our results demonstrate that the phenotypical changes of intercellular ZO-1 by oxidative stress via Nox4 likely contribute to the glomerular hyperpermeability caused by PAN.

Mucormycosis is an uncommon opportunistic fungal infection mostly affecting immunocompromised patients and gastrointestinal mucormycosis is a rare and life-threatening. We describe a 31-year-old man with a history of idiopathic cyclic neutropenia who developed perforations of the stomach and intestine and intra-abdominal bleeding due to disseminated gastrointestinal mucormycosis after the initial operation.

Nephrotic syndrome (NS) is a common chronic disease in children; in 90 percent of cases, the condition is primary (idiopathic). Toxic nephropathy can be induced by herbal medicines, and is mainly manifested as tubulointerstitial nephritis and rarely, as glomerulopathy. Here in, we describe two cases of steroid-sensitive NS, which developed after the patients received herbal medicines. A 5-year-old boy and an 8-year-old girl were separately admitted within a short time period with acute onset of generalized edema, proteinuria, hypoalbuminemia, and hypercholesterolemia. Each patient had previously taken herbal medicine, which had been prescribed by different oriental medical clinics for different conditions. The patients were diagnosed with herbal medicine-induced NS and were treated empirically by a standard steroid therapy, with subsequent resolution of their NS. One patient relapsed, but her NS again responded to steroid therapy. We described two unusual cases of prototypical pediatric, steroid-sensitive NS, which was presumed to be minimal-change disease that developed after the administration of herbal medicines. We also reviewed the literature.

Background Proteinuria is typically accompanied by structural and compositional changes of the foot processes and of the slit diaphragms between podocytes. CD2-associated protein (CD2AP) in podocytes serves as an adaptor protein binding to nephrin and podocin, anchoring these slit diaphragm proteins to actin filaments of podocyte cytoskeleton and sending signals inward or outward. Methods In the present study, we prepared streptozotocin-induced diabetic renal tissues and cultured podocytes in diabetic conditions to investigate podocyte phenotypical changes, including quantitative and distributional changes of CD2AP protein and search for the signalling mechanisms in diabetic conditions. We prepared cultured rat glomerular epithelial cells and mouse podocytes to study how high glucose and advanced glycosylation end products (AGE) induce phenotypical changes of cultured podocyte, under (1) normal glucose (5 mM, = control), (2) high glucose (30 mM), (3) AGE-added or (4) high glucose plus AGE-added conditions. Results According to diabetic duration, density of CD2AP in renal tissue of experimental diabetic nephropathy became conglomerulated and diminished. In cultured podocytes, CD2AP co-localized with nephrin and zonula occludens-1 by confocal imaging. High glucose and high glucose plus AGE induced the relocalization and concentration of CD2AP at internal cytoplasmic and perinuclear areas of podocytes. High glucose plus AGE-added condition also decreased CD2AP protein amount and its mRNA expression compared with normal glucose or osmotic control conditions. In addition, LY294002, a phosphoinositide 3-kinase inhibitor, prevented the quantitative and distributional changes of CD2AP induced by high glucose and AGE. Conclusions These findings suggest that diabetic conditions induce the phenotypical changes of podocyte CD2AP possibly via phosphoinositide 3-kinase/Akt signalling. Copyright © 2014 John Wiley & Sons, Ltd.

Background: The actin cytoskeleton in podocytes is essential for the maintenance of its normal structure and function. Its disruption is a feature of podocyte foot-process effacement and is associated with proteinuria. α-Actinin-4 in podocytes serves as a linker protein binding the actin filaments of the cytoskeleton. Methods: To investigate the effect of ginseng total saponin (GTS) on the pathological changes of podocyte α-actinin-4 induced by diabetic conditions, we cultured mouse podocytes under normal glucose (5mM) or high glucose (HG, 30mM) conditions, with or without the addition of advanced glycosylation end products (AGE), and treated with GTS. Results: In confocal imaging, α-actinin-4 colocalized with the ends of F-actin fibers in cytoplasm, but diabetic conditions disrupted F-actin fibers and concentrated α-actinin-4 molecules at the peripheral cytoplasm. GTS upregulated α-actinin protein in a time- and dose-dependent manner, and suppressed the receptor for AGE levels in western blotting. Diabetic conditions, including HG, AGE, and both together, decreased cellular α-actinin-4 protein levels at 24 h and 48 h. Such quantitative and qualitative changes of α-actinin-4 protein induced by diabetic conditions were mitigated by GTS. Conclusion: These findings imply that both HG and AGE have an influence on the distribution and amount of α-actinin-4 in podocytes that can be recovered by GTS.

Hypertrophy is a prominent feature of damaged podocytes in diabetic kidney disease (DKD). mTORC1 hyperactivation leads to podocyte hypertrophy, but the detailed mechanism of how mTORC1 activation occurs under pathological conditions is not completely known. Moreover, reduced nephrin tyrosine phosphorylation has been observed in podocytes under pathological conditions, but the molecular mechanism linking nephrin phosphorylation and pathology is unclear so far. In this study, we observed a significant increase in C1-Ten level in diabetic kidney and in high glucose-induced damaged podocytes. C1-Ten acts as a protein tyrosine phosphatase (PTPase) at the nephrin-PI3K binding site and renders PI3K for IRS-1, thereby activating mTORC1. Furthermore, C1-Ten causes podocyte hypertrophy and proteinuria by increasing mTORC1 activity in vitro and in vivo. These findings demonstrate the relationship between nephrin dephosphorylation and the mTORC1 pathway, mediated by C1-Ten PTPase activity. We suggest that C1-Ten contributes to the pathogenesis of DKD by inducing podocyte hypertrophy under high glucose conditions.

Background: Adenosine monophosphate-activated protein kinases (AMPKs), as a sensor of cellular energy status, have been known to play an important role in the pathophysiology of diabetes and its complications. Because AMPKs are known to be expressed in podocytes, it is possible that podocyte AMPKs could be an important contributing factor in the development of diabetic proteinuria. We investigated the roles of AMPKs in the pathological changes in podocytes induced by high-glucose (HG) and advanced glycosylation end products (AGEs) in diabetic proteinuria. Methods: We prepared streptozotocin-induced diabetic renal tissues and cultured rat and mouse podocytes under diabetic conditions with AMPK-modulating agents. The changes in AMPKα were analyzed with confocal imaging and Western blotting under the following conditions: (1) normal glucose (5mM, =control); (2) HG (30mM); (3) AGE-added; or (4) HG plus AGE-added. Results: The density of glomerularphospho-AMPKα in experimental diabetic nephropathy decreased as a function of the diabetic duration. Diabetic conditions including HG and AGE changed the localization of phospho-AMPKα from peripheral cytoplasm to internal cytoplasm and peri- and intranuclear areas in podocytes. HG reduced the AMPKα (Thr172) phosphorylation of rat podocytes, and similarly, AGEs reduced the AMPKα (Thr172) phosphorylation of mouse podocytes. The distributional and quantitative changes in phospho-AMPKα caused by diabetic conditions were preventable using AMPK activators, metformin, and 5-aminoimidazole-4-carboxamide-1β-riboside. Conclusion: We suggest that diabetic conditions induce the relocation and suppression of podocyte AMPKα, which would be a suggestive mechanism in diabetic podocyte injury.

The aim of this study was to compare the efficacy of combination therapy with desmopressin and an anticholinergic to desmopressin monotherapy for the first-line treatment of children with primary monosymptomatic nocturnal enuresis (PMNE).A total of 98 children with PMNE (male:female 71:27) aged 5-16 (mean age 7.18 ± 1.8) years were retrospectively analyzed. The patients were divided into two groups: the monotherapy group (n = 49) was given oral desmopressin alone, and the combination therapy group (n = 49) was given desmopressin plus an anticholinergic (propiverine 10 mg) as a first-line treatment. The two groups were matched according to the following criteria: age, gender, and baseline frequency of nocturnal enuresis. The efficacy was evaluated by International Children's Continence Society criteria at 1 and 3 months after treatment initiation.The combination therapy group showed a higher rate of complete response than the monotherapy group (20.4 vs. 6.1% at 1 month of treatment; 46.9 vs. 22.4% at 3 months of treatment). In terms of success (response and complete response), there was a significant difference between the two groups after 3 months of treatment (P = 0.002).Our results indicate that combination therapy with desmopressin plus an anticholinergic is quicker and more effective than desmopressin monotherapy in reducing PMNE.

OBJECTIVE AND DESIGN: Interleukin-13 (IL-13) has recently been reported to be a potential cytokine in the pathogenesis of minimal-change nephrotic syndrome (MCNS). However, the mechanistic insights associated with podocyte dysfunction mediated by IL-13-induced changes in various slit diaphragm (SD) and cytoskeletal molecules have not yet been shown in cultured human podocytes in vitro.MATERIALS: Human conditionally immortalized podocytes were used.TREATMENT: Podocytes were incubated with various concentrations of IL-13 during the indicated time periods (6, 12, and 24 h) and montelukast was administered with the dose of 0.1 μg.RESULTS: Treatment of IL-13 resulted in a progressive decrease in distinct processes or projections of the human podocytes and high dose of IL-13 increased podocyte permeability in vitro at 6 h. IL-13 had a substantial impact on the redistribution and rearrangement of zonula occludens (ZO)-1, synaptopodin, α-actinin, CD2-associated protein (CD2AP) in podocytes and disrupted the cytoskeletal connections in a concentration-dependent manner on confocal microscopy. IL-13 also down-modulated ZO-1, synaptopodin, α-actinin, CD2AP, and p130Cas at protein levels and upregulated β-catenin and B7-1 in podocytes. Furthermore, we demonstrated that down-modulated changes in various SD and cytoskeletal structures of human podocytes induced by IL-13 was significantly restored after treatment with montelukast with upregulation of B7-1.CONCLUSION: Our results suggest that targeting IL-13 may be one of the important cytokines in the pathogenesis of MCNS and targeting IL-13 could be one of the potential therapeutic strategies in MCNS.

Type I (distal) renal tubular acidosis (RTA) is a disorder associated with the failure to excrete hydrogen ions from the distal renal tubule. It is characterized by hyperchloremic metabolic acidosis, an abnormal increase in urine pH, reduced urinary excretion of ammonium and bicarbonate ions, and mild deterioration in renal function. Hypercalciuria is common in distal RTA because of bone resorption, which increases as a buffer against metabolic acidosis. This can result in intractable rickets. We describe a case of distal RTA with nephrocalcinosis during follow-up of rickets in a patient who presented with clinical manifestations of short stature, failure to thrive, recurrent vomiting, dehydration, and irritability.

Proteinuric conditions demonstrate structural and compositional changes of the foot processes and slit diaphragms between podocytes. p130Cas in podocytes serves as an adapter protein anchoring glomerular basement membrane to actin filaments of podocyte cytoskeleton. To investigate the effect of ginseng total saponin (GTS) on the pathologic changes of podocyte p130Cas induced by diabetic conditions, we cultured mouse podocytes under: 1) normal glucose (5 mM, control); 2) high glucose (HG, 30 mM); 3) advanced glycosylation endproducts (AGE)-added; or 4) HG plus AGE-added conditions and treated with GTS. In confocal imaging, p130Cas colocalized with zonula occludens-1 and synaptopodin connecting to F-actin. However, diabetic conditions relocalized p130Cas molecules at perinuclear cytoplasmic area and reduced the intensity of p130Cas. In Western blotting, diabetic conditions, especially HG plus AGE-added condition, decreased cellular p130Cas protein levels at 24 and 48 h. GTS improved such quantitative and qualitative changes. These findings imply that HG and AGE have an influence on the redistribution and amount of p130Cas of podocytes, which can be reversed by GTS.

Since 1998, urine screening tests have been performed on school children in Korea. We report the findings of the screening program that analyzed patients with proteinuria and/or hematuria. Between 1999 and 2008, 5,114 children were referred to pediatric nephrologists at seven nationwide hospitals. Renal biopsies were performed on 1,478 children [28.79 % of total subjects; 26.77 % for isolated hematuria (IH), 9.09 % for isolated proteinuria (IP), and 51.19 % for combined hematuria and proteinuria (CHP)] who showed abnormal renal function, persistent hematuria and/or proteinuria for more than 6 months, nephrotic-range proteinuria, or those with underlying systemic diseases. Chronic glomerulonephritis (GN) was detected in 25 % of all visiting subjects. The most common findings in renal biopsies were immunoglobulin A (IgA) nephropathy in 38.97 %, mesangial proliferative GN in 24.29 %, and thin basement membrane nephropathy in 13.13 %. Compared with the relative frequency of renal diseases associated with urinary abnormalities, CHP (46.90 %) and nephrotic-range proteinuria (69.96 %) groups had more frequent GN than the others. Abnormal findings on renal ultrasound with or without Doppler scan were noted in 462 cases (suspected nutcracker phenomenon, 159; increased parenchymal echogenicity, 92; hydronephrosis, 75; simple cyst, 47). Mass urine screening tests could detect asymptomatic GN in its early stages. Initial aggressive diagnosis and treatment for CHP and nephrotic-range groups may prove helpful as interventions that delay chronic kidney disease progression. These findings may assist in the development of diagnostic and management guidelines for relatively mild urinary abnormalities, such as IH or low-grade IP.

Purpose Puromycin aminonucleoside (PAN) specifically injures podocytes, leading to foot process effacement, actin cytoskeleton disorganization, and abnormal distribution of slit diaphragm proteins. p130Cas is a docking protein connecting F-actin fibers to the glomerular basement membrane (GBM) and adapter proteins in glomerular epithelial cells (GEpCs; podocytes). We investigated the changes in the p130Cas expression level in the PAN-induced pathological changes of podocytes in vitro. Methods We observed changes in the p130Cas expression in cultured rat GEpCs and mouse podocytes treated with various concentrations of PAN and antioxidants, including probucol, epigallocatechin gallate (EGCG), and vitamin C. The changes in the p130Cas expression level were analyzed using confocal immunofluorescence imaging, Western blotting, and polymerase chain reaction. Results In the immunofluorescence study, p130Cas showed a diffuse cytoplasmic distribution with accumulation at distinct sites visible as short stripes and colocalized with P-cadherin. The fluorescences of the p130Cas protein were internalized and became granular by PAN administration in a dose-dependent manner, which had been restored by antioxidants, EGCG and vitamin C. PAN also decreased the protein and mRNA expression levels of p130Cas at high doses and in a longer exposed duration, which had been also reversed by antioxidants. Conclusion These findings suggest that PAN modulates the quantitative and distributional changes of podocyte p130Cas through oxidative stress resulting in podocyte dysfunction.

Proteinuric conditions demonstrate structural and compositional changes of the foot processes and slit diaphragms between podocytes. β-Catenin in podocytes serves as an adapter protein anchoring P-cadherin of slit diaphragms to actin filaments of podocyte cytoskeleton. To investigate the effect of ginseng total saponin (GTS) on the pathologic changes of podocyte P-cadherin/β-catenin unit induced by diabetic conditions, we cultured mouse podocytes under: 1) normal glucose (5 mM, = control); 2) high glucose (HG, 30 mM); 3) advanced glycosylation end products (AGE)-added; or 4) HG plus AGE-added conditions and treated with GTS. In confocal imaging, β-catenin colocalized with P-cadherin at intercellular junction area, predominantly. However, diabetic conditions relocalized and concentrated both molecules at perinuclear cytoplasmic area. In Western blotting, diabetic conditions, especially HG plus AGE-added condition, also decreased cellular β-catenin protein levels at 6, 24, and 48 hours. GTS improved such quantitative and qualitative changes of β-catenin. These findings imply that HG plus AGE have an influence on the redistribution and amount of P-cadherin/β-catenin unit of podocytes, which can be reversed by GTS.

Adenosine monophosphate (AMP)-activated protein kinase (AMPK), as a sensor of cellular energy status, has been known to play an important role in the pathophysiology of diabetes and its complications. As AMPK is also expressed in podocytes, it is possible that podocyte AMPK would be an important contributing factor in the development of diabetic proteinuria. We investigated the roles of AMPK in the pathological changes of podocytes induced by angiotensin II (Ang II), a major injury inducer in diabetic proteinuria. Mouse podocytes were incubated in media containing various concentrations of Ang II and AMPK-modulating agents. The changes of AMPKα were analyzed by confocal imaging and Western blotting in response to Ang II. Ang II changed the localization of AMPKα from peripheral cytoplasm into internal cytoplasm and peri- and intranuclear areas in podocytes. Ang II also reduced AMPKα (Thr172) phosphorylation in time- and dose-sensitive manners. In particular, 10−7 M Ang II reduced phospho-AMPKα significantly and continuously at 6, 24, and 48 h. AMPK activators, metformin and 5-aminoimidazole-4-carboxamide-1β-riboside, restored the suppressed AMPKα (Thr172) phosphorylation. Losartan, an Ang II type 1 receptor antagonist, also recovered the suppression and the mal-localization of AMPKα, which were induced by Ang II. PD98059, a mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor, also restored the AMPKα (Thr172) phosphorylation suppressed by Ang II. We suggest that Ang II induces the relocation and suppression of podocyte AMPKα via Ang II type 1 receptor and MAPK signaling pathway, which would be an important mechanism in Ang II-induced podocyte injury.

Serum lactate clearance (LC) during initial resuscitation is a potentially useful prognostic marker in patients with severe sepsis or septic shock. However, it is unclear whether LC is also associated with the outcome in septic patients with hepatic dysfunction that may impair lactate elimination, which may contribute to elevated serum lactate levels or decreased LC.The relationships between LC measured within 6 and 24h after initial resuscitation and hospital mortality were evaluated with multiple logistic regression analysis.Of 770 patients with severe sepsis or septic shock, 208 (27%) with hepatic dysfunction were included in the analysis. The median LC within 6h in survivors (31.4%) was significantly higher than that of non-survivors (9.3%) (P=.010). In addition, the median LC within 24h was also significantly different between groups (51% vs. 12%, P.001). Low LCs, defined as less than 10% of clearance, at 6 and 24h were associated with in-hospital mortality. After adjusting for potential confounding factors, low LCs at 6 and 24h remained associated with hospital mortality (adjusted OR 4.940, 95% CI 1.762-13.854 at 6h; adjusted OR 5.997, 95% CI 2.149-16.737 at 24h). However, LC at 24h (area under the curve of 0.704) had higher discriminatory power to predict hospital mortality than LC at 6h (area under the curve of 0.608) (P=.033).LC may be useful for predicting outcomes in septic patients with hepatic dysfunction.

Early diabetic nephropathy is characterized by glomerular hyperpermeability as a result of impaired glomerular filtration structure caused by hyperglycemia, glycated proteins or irreversible advanced glycosylation endproducts (AGE). To investigate the effect of ginseng total saponin (GTS) on the pathologic changes of podocyte ZO (zonula occludens)-1 protein and podocyte permeability induced by diabetic conditions, we cultured mouse podocytes under: 1) normal glucose (5 mM, = control); 2) high glucose (HG, 30 mM); 3) AGE-added; or 4) HG plus AGE-added conditions and treated with GTS. HG and AGE increased the dextran filtration of monolayered podocytes at early stage (2-8 hr) in permeability assay. In confocal imaging, ZO-1 colocalized with actin filaments and β-catenin at cell contact areas, forming intercellular filtration gaps. However, these diabetic conditions suppressed ZO-1 immunostainings and disrupted the linearity of ZO-1. In Western blotting, diabetic conditions also decreased cellular ZO-1 protein levels at 6 hr and 24 hr. GTS improved such quantitative and qualitative changes. These findings imply that HG and AGE have an influence on the redistribution and amount of ZO-1 protein of podocytes thereby causing hyperpermeability at early stage, which can be reversed by GTS.

Objectives To evaluate the prevalence of abnormal voiding and bowel habits in healthy children, and to identify possible relationships between personal and familial factors and voiding and/or bowel habits. Methods A randomly selected cross-sectional study was conducted in 19 240 children (5-13 years old) nationwide in the Republic of Korea. Parents were asked to complete questionnaires, which included items about nocturnal enuresis, daytime dysfunctional voiding symptoms (DVSs), and abnormal bowel habits (ABHs). Rates and associated factors were investigated. Results The overall rates of DVS, ABH, and of both were 46.4%, 31.3%, and 18.4%, respectively, and nocturnal enuresis was reported in 919 (5.6%). Daytime dysfunctional voiding symptoms were as follows: increased voiding frequency in 419 (2.5%), decreased voiding frequency in 720 (4.4%), urgency in 2740 (16.6%), daytime incontinence in 1854 (11.2%), urge incontinence in 2775 (16.8%), and holding maneuvers or postponed voiding in 3888 (23.5%). ABHs were as follows: constipation by frequency in 1103 (6.7%), constipation by the Bristol scale in 1941 (11.8%), fecal incontinence in 1293 (7.8%), and difficult or painful defecation in 2609 (15.8%). Delayed stool control, history of urinary tract infection, and a double-income family were positively associated with DVS or ABH or both. Furthermore, fathers with a low level of education and a low income were found to be associated with higher risk of ABH or DVS or both. Conclusions Delayed stool control, a history of urinary tract infection, a low paternal level of education, a double-income family, and a lower family income had a negative effect on voiding or bowel habits in children.