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Klippel-Trenaunay syndrome (KTS) is a rare syndrome, which is clinically diagnosed by the presence of unilateral limb hypertrophy with vascular malformation including cutaneous capillaries, veins and lymphatic vessels. Most cases typically exhibit cutaneous manifestations such as port-wine stains and limb hypertrophy from infancy, but cases with mild manifestations may remain undiagnosed. We here report a case of KTS who was diagnosed by chance chyluria. A 15-year-old girl who exhibited hematochyluria with nephrotic-range proteinuria was referred to our hospital. She had been diagnosed as idiopathic scoliosis accompanied by left lower limb hypertrophy in the past. She noticed her milky urine for the first time two months before. Immediately thereafter, she noticed edema of her left leg. Hematochyluria with nephrotic-range proteinuria was found by our initial urine examination. Magnetic resonance imaging suggested venous or lymphatic malformation along the left common iliac vein at the retroperitoneal side. Lymphoscintigraphy showed congestion of radioisotope around backside of the pancreas to the left renal hilus, suggesting an existence of lymphostasis. Based on the findings, we diagnosed the patient as KTS. After admission, hematochyluria and proteinuria were decreased and became insignificant by three days with bed rest. Her left leg edema was reduced. After taking a guidance to avoid intensive exercise, she was discharged in two weeks. Because the present case exhibited mild manifestations, diagnosis was made by urine abnormalities for the first time. The case suggests that we should be aware of the presence of undiagnosed patients of KTS due to relatively mild manifestations.

Please see the Editorial Comment by Brian M. Haas discussing this article. BACKGROUND. Acute exacerbation (AE) is a life-threatening complication of inter-stitial pneumonia (IP). Thoracic surgery m...

Metabolic syndrome (MetS) is associated with chronic kidney disease and proteinuria. Previously, we reported that a synthetic serine protease inhibitor, camostat mesilate (CM), mitigated hypertension and proteinuria in rodent disease models. The present study evaluated the anti-hypertensive and anti-proteinuric effects of CM in MetS model rats (SHR/ND mcr-cp). Rats were divided into normal salt-fed (NS), high salt-fed (HS), HS and CM-treated (CM), and HS and hydralazine-treated (Hyd) groups. Rats were sacrificed after four weeks of treatment. Severe hypertension and proteinuria were observed in the HS group. Although CM and Hyd equally alleviated hypertension, CM suppressed proteinuria and glomerular sclerosis more efficiently than Hyd. The HS group revealed a decrease in podocyte number and podocyte-specific molecules, together with an increase in glomerular apoptotic cells and apoptosis-related proteins in the kidney. These changes were significantly attenuated by CM, but not by Hyd. Furthermore, CM ameliorated the apoptotic signals in murine cultured podocytes stimulated with the high glucose and aldosterone medium. In conclusion, CM could exert renoprotective effects in MetS model rats, together with the inhibition of podocyte apoptosis. Our study suggests that serine protease inhibition may become a new therapeutic strategy against MetS-related hypertension and renal injuries.

Salt-sensitive hypertension is associated with poor clinical outcomes. The epithelial sodium channel (ENaC) in the kidney plays pivotal roles in sodium reabsorption and blood pressure regulation, in which its γ subunit is activated by extracellular serine proteases. In proteinuric nephropathies, plasmin filtered through injured glomeruli reportedly activates γENaC in the distal nephron and causes podocyte injury. We previously reported that Dahl salt-sensitive (DS) rats fed a high-salt (HS) diet developed hypertension and proteinuria along with γENaC activation and that a synthetic serine protease inhibitor, camostat mesilate, mitigated these changes. However, the role of plasmin in DS rats remained unclear. In this study, we evaluated the relationship between plasmin and hypertension as well as podocyte injury and the effects of plasmin inhibitors in DS rats. Five-week-old DS rats were divided into normal-salt diet, HS diet, and HS+plasmin inhibitor (either tranexamic acid [TA] or synthetic plasmin inhibitor YO-2) groups. After blood pressure measurement and 24 h urine collection over 5 weeks, rats were sacrificed for biochemical analyses. The HS group displayed severe hypertension and proteinuria together with activation of plasmin in urine and γENaC in the kidney, which was significantly attenuated by YO-2 but not TA. YO-2 inhibited the attachment of plasmin(ogen) to podocytes and alleviated podocyte injury by inhibiting apoptosis and inflammatory/profibrotic cytokines. YO-2 also suppressed upregulation of protease-activated receptor-1 and phosphorylated ERK1/2. These results indicate an important role of plasmin in the development of salt-sensitive hypertension and related podocyte injury, suggesting plasmin inhibition as a potential therapeutic strategy.

Rhesus C glycoprotein (Rhcg), an ammonia transporter, is a key molecule in urinary acid excretion and is expressed mainly in the intercalated cells (ICs) of the renal collecting duct. In the present study we investigated the role of aldosterone in the regulation of Rhcg expression. In in vivo experiments using C57BL/6J mice, Western blot analysis showed that continuous subcutaneous administration of aldosterone increased the expression of Rhcg in membrane fraction of the kidney. Supplementation of potassium inhibited the effect of aldosterone on the Rhcg. Next, mice were subjected to adrenalectomy with or without administration of aldosterone, and then ad libitum 0.14 M NH4Cl containing water was given. NH4Cl load increased the expression of Rhcg in membrane fraction. Adrenalectomy decreased NH4Cl-induced Rhcg expression, which was restored by administration of aldosterone. Immunohistochemical studies revealed that NH4Cl load induced the localization of Rhcg at the apical membrane of ICs in the outer medullary collecting duct. Adrenalectomy decreased NH4Cl-induced membrane localization of Rhcg, which was restored by administration of aldosterone. For in vitro experiments, IN-IC cells, an immortalized cell line stably expressing Flag-tagged Rhcg (Rhcg-Flag), were used. Western blot analysis showed that aldosterone increased the expression of Rhcg-Flag in membrane fraction, while the increase in extracellular potassium level inhibited the effect of aldosterone. Both spironolactone and Gӧ6983, a PKC inhibitor, inhibited the expression of Rhcg-Flag in the membrane fraction. These results suggest that aldosterone regulates the membrane expression of Rhcg through the mineralocorticoid receptor and PKC pathways, which is modulated by extracellular potassium level.

Acute kidney injury (AKI) is a life-threatening condition and often progresses to chronic kidney disease or the development of other organ dysfunction even after recovery. Despite the increased recognition and high prevalence of AKI worldwide, there has been no established treatment so far. The aim of this study was to investigate the renoprotective effect of Kyoto University substance 121 (KUS121), a novel valosin-containing protein modulator, on AKI. In in vitro experiments, we evaluated cell viability and ATP levels of proximal tubular cells with or without KUS121 under endoplasmic reticulum (ER) stress conditions. In in vivo experiments, the effects of KUS121 were examined in mice with AKI caused by ischemia-reperfusion injury. ER-associated degradation (ERAD)-processing capacity was evaluated by quantification of the ERAD substrate CD3delta-YFP. KUS121 protected proximal tubular cells from cell death under ER stress. The apoptotic response was mitigated as indicated by the suppression of C/EBP homologous protein expression and caspase-3 cleavage, with maintained intracellular ATP levels by KUS121 administration. KUS121 treatment suppressed the elevation of serum creatinine and neutrophil gelatinase-associated lipocalin levels and attenuated renal tubular damage after ischemia-reperfusion. The expression of inflammatory cytokines in the kidney was also suppressed in the KUS121-treated group. Valosin-containing protein expression levels were not altered by KUS121 both in vitro and in vivo. KUS121 treatment restored ERAD-processing capacity associated with potentiation of its upstream pathway, phosphorylated inositol-requiring enzyme-1α, and spliced X box-binding protein-1. In conclusion, these findings indicate that KUS121 can protect renal tubular cells from ER stress-induced injury, suggesting that KUS121 could be a novel and promising therapeutic compound for ischemia-associated AKI.

Purpose Totally implantable central venous access port implantation is typically performed in the supine position. However, some patients cannot adopt the supine position due to severe pain and/or dyspnea. The present study evaluated the technical feasibility of peripherally inserted central catheter port system (PICC-PORT) implantation in the sitting position in such cases. Materials and methods In the sitting position method, PICC-PORT implantation was performed with the patients seated on a videofluoroscopy chair positioned between the limbs of an angiographic C-arm and the operative upper arm positioned on an arm stand. From January 2019 to September 2021, eight patients underwent PICC-PORT implantations using this sitting method. We also evaluated 251 consecutive patients with conventional supine position PICC-PORT implantation as controls. Differences in technical success, procedure time and complications were retrospectively assessed between the two groups. Results Procedural success rates were 100% in both groups. Median procedure times in the sitting and conventional groups were 42 and 44 min, respectively. No complications were observed in the sitting group. There were no significant differences between the two groups in procedure time (p = 0.674) and complications (p = 1.000). Conclusion Implantation of PICC-PORT in the sitting position is technically feasible and useful.

Mesangial lesions and podocyte injury are essential manifestations of the progression of diabetic kidney disease (DKD). Although cross-communication between mesangial cells (MCs) and podocytes has recently been suggested by the results of single-nucleus RNA sequencing analyses, the molecular mechanisms and role in disease progression remain elusive. Our cDNA microarray data of diabetic mouse glomeruli suggested the involvement of endoplasmic reticulum (ER) stress in DKD pathophysiology. In vitro experiments revealed the suppression of the ER-associated degradation (ERAD) pathway and induction of apoptosis in podocytes that were stimulated with the supernatant of MCs cultured in high glucose conditions. In diabetic mice, ERAD inhibition resulted in exacerbated albuminuria, increased apoptosis in podocytes, and reduced nephrin expression associated with the downregulation of ERAD-related biomolecules. Flow cytometry analysis of podocytes isolated from MafB (a transcription factor known to be expressed in macrophages and podocytes)-GFP knock-in mice revealed that ERAD inhibition resulted in decreased nephrin phosphorylation. These findings suggest that an intraglomerular cross talk between MCs and podocytes can inhibit physiological ERAD processes and suppress the phosphorylation of nephrin in podocytes, which thereby lead to podocyte injury under diabetic conditions. Therapeutic intervention of the ERAD pathway through the cross talk between these cells is potentially a novel strategy for DKD.

Hemorrhage arising from the coronary sinus is very rare and can be lethal. It has historically been treated surgically. The present patient had coronary sinus rupture secondary to esophageal cancer and an abscess in the pericardium. Due to her poor general status, this patient was contraindicated for surgery and underwent endovascular therapy. The hemorrhage was treated by stent graft deployment and the patient was temporarily discharged. Two months later, CT showed that the stent graft was occluded by thrombosis. The patient died without hemorrhage 2.5 months thereafter.

Endometrial cancer arising from adenomyosis (EC-AIA) is extremely rare, and the typical magnetic resonance imaging (MRI) findings of EC-AIA have not been established. We report a case of EC-AIA that was detected preoperatively on MRI and conduct a literature review of the MRI findings of EC-AIA. Keywords: Endometrial cancer, Uterine cancer, Adenomyosis, Magnetic resonance imaging

Toll-like receptor 4 (TLR4) and one of its endogenous ligands myeloid-related protein 8 (MRP8 or S100A8), especially expressed in macrophages, play an important role in diabetic nephropathy and autoimmune disorders. However, detailed mechanisms and consequence of MRP8 expression remain unknown, partly due to embryonic lethality of MRP8 knockout mice. In this study, Myeloid lineage cell-specific MRP8 knockout mice were generated, and nephrotoxic serum-induced glomerulonephritis was developed. Mice with conditional ablation of MRP8 gene in myeloid cells exhibited less severe histological damage, proteinuria and inflammatory changes compared to control mice. Mechanism of MRP8 upregulation was investigated using cultured cells. Co-culture of macrophages with mesangial cells or mesangial cell-conditioned media, but not with proximal tubules, markedly upregulated MRP8 gene expression and inflammatory M1 phenotype in macrophages, which was attenuated in MRP8-deleted bone marrow-derived macrophages. Effects of MRP8 deletion was further studied in the context of macrophage-inducible C-type lectin (Mincle), which is critically involved in maintenance of M1 phenotype of macrophages. MRP8 ablation in myeloid cells suppressed the induction of Mincle expression on macrophages in glomerulonephritis. Thus, we propose that intraglomerular crosstalk between mesangial cells and macrophages plays a role in inflammatory changes in glomerulonephritis, and MRP8-dependent Mincle expression in macrophage may be involved in the process.

Background Patients undergoing hemodialysis treatment have a poor prognosis, as many develop premature aging. Systemic inflammatory conditions often underlie premature aging phenotypes in uremic patients. We investigated whether angiopoietin-like protein 2 (ANGPTL 2), a factor that accelerates the progression of aging-related and noninfectious inflammatory diseases, was associated with increased mortality risk in hemodialysis patients. Methods We conducted a multicenter prospective cohort study of 412 patients receiving maintenance hemodialysis and evaluated the relationship between circulating ANGPTL2 levels and the risk for all-cause mortality. Circulating ANGPTL2 levels were log-transformed to correct for skewed distribution and analyzed as a continuous variable. Results Of 412 patients, 395 were included for statistical analysis. Time-to-event data analysis showed high circulating ANGPTL2 levels were associated with an increased risk for all-cause mortality after adjustment for age, sex, hemodialysis vintage, nutritional status, metabolic parameters and circulating high-sensitivity C-reactive protein levels {hazard ratio [HR] 2.04 [95% confidence interval (CI) 1.10–3.77]}. High circulating ANGPTL2 levels were also strongly associated with an increased mortality risk, particularly in patients with a relatively benign prognostic profile [HR 3.06 (95% CI 1.86–5.03)]. Furthermore, the relationship between circulating ANGPTL2 levels and mortality risk was particularly strong in patients showing few aging-related phenotypes, such as younger patients [HR 7.99 (95% CI 3.55–18.01)], patients with a short hemodialysis vintage [HR 3.99 (95% CI 2.85–5.58)] and nondiabetic patients [HR 5.15 (95% CI 3.19–8.32)]. Conclusion We conclude that circulating ANGPTL2 levels are positively associated with mortality risk in patients receiving maintenance hemodialysis and that ANGPTL2 could be a unique marker for the progression of premature aging and subsequent mortality risk in uremic patients, except those with significant aging-related phenotypes.

Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys.

The kidney plays a crucial role in blood pressure (BP) regulation by controlling sodium reabsorption along the nephron. NFAT5 (nuclear factor of activated T-cells 5) is a transcription factor that is expressed in various tissues including the kidney and is activated at hypertonic conditions as observed in the renal medulla; the role for kidney NFAT5 in BP regulation, however, remains still obscure. In the present study, we generated inducible and renal tubular cell–specific NFAT5 knockout (KO) mice and characterized their phenotype. The NFAT5 KO mice exhibited high BP, hypernatremia, polyuria, and low urinary sodium excretion without significant alterations in the plasma renin activity or aldosterone concentration. The mice fed a high-salt diet further increased BP, revealing salt-sensitive hypertension. The KO mice exhibited the increased gene expression of the epithelial sodium channel. Protein expression of epithelial sodium channel in the membrane fraction was also significantly increased in KO mice than in wild-type mice. Treatment with amiloride, an epithelial sodium channel blocker, corrected high BP, hypernatremia, and decreased urinary sodium excretion in KO mice to the same levels of those in wild-type mice. Finally, the effects of high-salt diet and amiloride in KO mice were confirmed by the radiotelemetry method. In conclusion, these data indicate that renal tubular NFAT5 should play an important role in regulating sodium reabsorption through epithelial sodium channel under high-salt conditions, thereby preventing salt-dependent hypertension.

The kidney is a main site of erythropoietin production in the body. We developed a new method for the detection of Epo protein by deglycosylation-coupled Western blotting. Detection of deglycosylated Epo enables the examination of small changes in Epo production. Using this method, we investigated the effects of angiotensin II (ATII) on Epo production in the kidney. ATII stimulated the plasma Epo concentration, Epo, HIF2α, and PHD2 mRNA expression in nephron segments in the renal cortex and outer medulla, and Epo protein expression in the renal cortex. In situ hybridization and immunohistochemistry revealed that ATII stimulates Epo mRNA and protein expression not only in proximal tubules but also in collecting ducts, especially in intercalated cells. These data support the regulation of Epo production in the kidney by the renin–angiotensin–aldosterone system (RAS).

To evaluate the radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) under X-ray imaging. SAP-MS were suspended in contrast material (iodixanol) and the diameter change was assessed. The diameter of contrast-loaded SAP-MS in saline was measured sequentially. Radiography of the contrast-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio and visibility by multiple reader scoring. Under digital subtraction angiography, contrast-loaded SAP-MS were injected into a flow model. The flow speed was 1–10 cm/s, and images were acquired at 1–7.5 frames per second using a pulse width of 10–85 ms. Images were assessed by multiple reader scoring. The diameter of SAP-MS increased to 4.0–5.0 times its original size for approximately 15 min. The diameter of contrast-loaded SAP-MS in saline further increased by 10–30% within several minutes and returned to the previous size. Radiopacity and visibility of contrast-loaded SAP-MS decreased in 30 min after mixing with saline. Visibility was better with slow flow speed and narrow pulse width. For effective observation, contrast-loaded SAP-MS should be kept in non-diluted contrast material until use. The conditions of slower flow and use of a narrow pulse width are recommended.

Background Osteocrin (OSTN), a bone-derived humoral factor, was reported to act on heart and bone by potentiating the natriuretic peptide (NP) system. Ostn gene polymorphisms have been associated with renal function decline, but its pathophysiological role in the kidney remains unclear. Methods The role of endogenous OSTN was investigated using systemic Ostn-knockout (KO) mice. As a model for OSTN administration, liver-specific Ostn-overexpressing mice crossed with KO (KO-Tg) were generated. These mice were subjected to unilateral ischemia–reperfusion injury (IRI) and renal lesions after 21 days of insult were evaluated. A comprehensive analysis of the Wnt/β-catenin pathway was performed using a polymerase chain reaction (PCR) array. Reporter plasmid-transfected proximal tubular cells (NRK52E) were used to investigate the mechanism by which OSTN affects the pathway. Results After injury, KO mice showed marginal worsening of renal fibrosis compared with wild-type mice, with comparable renal atrophy. KO-Tg mice showed significantly ameliorated renal atrophy, fibrosis and tubular injury, together with reduced expressions of fibrosis- and inflammation-related genes. The PCR array showed that the activation of the Wnt/β-catenin pathway was attenuated in KO-Tg mice. The downstream targets Mmp7, Myc and Axin2 showed similar results. MMP7 and Wnt2 were induced in corticomedullary proximal tubules after injury, but not in KO-Tg. In NRK52E, OSTN significantly potentiated the inhibitory effects of NP on transforming growth factor β1–induced activation of the Wnt/β-catenin pathway, which was reproduced by a cyclic guanosine monophosphate analog. Conclusions Ectopic Ostn overexpression ameliorated subsequent renal injury following ischemia–reperfusion. OSTN could represent possible renoprotection in acute to chronic kidney disease transition, thus serving as a potential therapeutic strategy.

Doping tests for the illegal use of erythropoiesis-stimulating agents (ESAs) have been developed. We developed a new Western blotting method to detect and distinguish endogenous erythropoietin (Epo, 35-38 kDa) and exogenous ESAs (epoetin α and β, 38-42 kDa; darbepoetin α, 47-50 kDa; epoetin β pegol, 93-110 kDa). Epo and ESAs are glycoproteins and deglycosylation using peptide-N-glycosidase F shifted all Epo and ESA bands except epoetin β pegol to 22 kDa. We cut the bands of Epo and ESAs from SDS-PAGE gels and analyzed them by Liquid Chromatography/Mass Spectrometry (LC/MS). LC/MS detected all endogenous Epo and exogenous ESAs as deglycosylated 22 kDa Epo, indicating that LC/MS analysis could confirm the presence of Epo or ESA, but could not distinguish between endogenous Epo and exogenous ESAs. We propose the following Epo doping tests: 1) detect Epo or ESAs by Western blotting of the glycosylated form; 2) increase the reliability by the band shift following deglycosylation; and 3) complete confirmation of Epo or ESA by LC/MS analysis using cut gels. One of the advantages of our method is that pre-purification of samples for Epo is not required in our Western blotting., Biotechnology; Biochemistry; Molecular Biology; Public Health; Hematological System; Renal System; erythropoietin, erythropoiesis-stimulating agents, Western blotting, Liquid Chromatography/Mass Spectrometry analysis, doping, endogenous, exogenous.

Background and aims Chronic low-grade inflammation is receiving much attention as a critical pathology that induces various aging phenotypes, a concept known as “inflammaging”. Uremic patients undergoing hemodialysis therapy show vascular aging phenotypes characterized by greater arterial stiffness and calcification compared to healthy controls of the same generation. In the current study, we investigated whether levels of inflammaging markers in the circulation were associated with vascular aging phenotypes in hemodialysis patients, as estimated by the cardio-ankle vascular index (CAVI). Methods We conducted a multicenter cross-sectional study of 412 patients receiving hemodialysis and evaluated the relationship between circulating hs-CRP or ANGPTL2 levels, as markers of inflammaging, and CAVI. Results Of 412 patients, 376 were analyzed statistically. While circulating hs-CRP levels had no significant association with CAVI, generalized linear models revealed that high circulating ANGPTL2 levels were significantly associated with increasing CAVI after adjustment for classical metabolic factors and hemodialysis-related parameters [β 0.63 (95%CI 0.07–1.18)]. Exploratory analysis revealed that high circulating ANGPTL2 levels were also strongly associated with increased CAVI, particularly in patients with conditions of increased vascular mechanical stress, such elevated blood pressure [β 1.00 (95%CI 0.23–1.76)], elevated pulse pressure [β 0.75 (95%CI 0.52–0.98)], or excess body fluid [β 1.25 (95%CI 0.65–1.84)]. Conclusions We conclude that circulating levels of ANGPTL2 rather than hs-CRP are positively associated with CAVI in the uremic population and that ANGPTL2 could be a unique marker of progression of vascular aging in patients receiving hemodialysis.