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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.

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.

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.

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.

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.

Revised JPN guidelines for the management of acute pancreatitis: JPN guidelines 2015 Toshihiko Mayumi, Tadahiro Takada, Masamichi Yokoe, Masahiro Yoshida University of Occupational and Environmental Health, Japan Teikyo University School of Medicine, Japan Japanese Red Cross Nagoya Daini Hospital, Japan Clinical Research Center Kaken Hospital, International University of Health and Welfare, Japan Background/Purpose: JPN guidelines for the management of acute pancreatitis were published in 2003 and revised in 2007 and 2009 that the severity assessment score has been highly regarded all over the world. Since the classification and the definition of acute pancreatitis had been changed significantly in the New Atlanta classification of acute pancreatitis 2012, the working group of JPN guidelines revised JPN guidelines with making new meta-analysis and using the GRADE system. Methods: The working group of revising JPN guidelines consists of 28 specialists, surgeons, gastroenterologists, endoscopists, radiologists, and epidemiologists. Results: JPNguidelines 2015 containmajor topics as described below: (1) epidemiology and etiology, (2) diagnostic criteria, (3) severity scoring system, (4) fundamental and intensive care with flowcharts, (5) therapeutic intervention and surgery, (6) post-ERCP pancreatitis, (7) treatment strategy, (8) clinical indicator andpancreatitis bundles, and (9) imaging. JPN guidelines also released mobile applications for the management of acute pancreatitis. Meta-analyses were performed on prophylactic antibiotic use for the prevention of necrotizing pancreatitis and reduction of mortality and on prophylactic pancreatic stent placement for the prevention of post-ERCP pancreatitis. These metaanalysis data have the results that significant effects are expected to each setting. JPN guidelines 2015 take advantage of this brand-new evidence for the new idea for the treatment of acute pancreatitis. Conclusions: Revised JPN guidelines 2015 achieve further evolution with new meta-analysis data and contain a lot of recommendations using the GRADE system for clinical use.