Ceria-Zirconia nanoparticles reduce intracellular globotriaosylceramide accumulation and attenuate kidney injury by enhancing the autophagy flux in cellular and animal models of Fabry disease.

BACKGROUND: Fabry disease (FD) is a lysosome storage disease (LSD) characterized by significantly reduced intracellular autophagy function. This contributes to the progression of intracellular pathologic signaling and can lead to organ injury. Phospholipid-polyethyleneglycol-capped Ceria-Zirconia antioxidant nanoparticles (PEG-CZNPs) have been reported to enhance autophagy flux. We analyzed whether they suppress globotriaosylceramide (Gb3) accumulation by enhancing autophagy flux and thereby attenuate kidney injury in both cellular and animal models of FD. RESULTS: Gb3 was significantly increased in cultured human renal proximal tubular epithelial cells (HK-2) and human podocytes following the siRNA silencing of α galactosidase A (α-GLA). PEG-CZNPs effectively reduced the intracellular accumulation of Gb3 in both cell models of FD and improved both intracellular inflammation and apoptosis in the HK-2 cell model of FD. Moreover these particles attenuated pro fibrotic cytokines in the human podocyte model of FD. This effect was revealed through an improvement of the intracellular autophagy flux function and a reduction in reactive oxygen species (ROS). An FD animal model was generated in which 4-week-old male B6;129-Glatm1Kul/J mice were treated for 8 weeks with 10 mg/kg of PEG-CZNPs (twice weekly via intraperitoneal injection). Gb3 levels were reduced in the kidney tissues of these animals, and their podocyte characteristics and autophagy flux functions were preserved. CONCLUSIONS: PEG-CZNPs alleviate FD associated kidney injury by enhancing autophagy function and thus provide a foundation for the development of new drugs to treat of storage disease.

Discoidin Domain Receptor 2 Mediates Lysophosphatidic Acid-Induced Ovarian Cancer Aggressiveness.

Lysophosphatidic acid (LPA), a bioactive lipid produced extracellularly by autotaxin (ATX), has been known to induce various pathophysiological events, including cancer cell invasion and metastasis. Discoidin domain receptor 2 (DDR2) expression is upregulated in ovarian cancer tissues, and is closely associated with poor clinical outcomes in ovarian cancer patients. In the present study, we determined a critical role and signaling cascade for the expression of DDR2 in LPA-induced ovarian cancer cell invasion. We also found ectopic expression of ATX or stimulation of ovarian cancer cells with LPA-induced DDR2 expression. However, the silencing of DDR2 expression significantly inhibited ATX- and LPA-induced ovarian cancer cell invasion. In addition, treatment of the cells with pharmacological inhibitors of phosphoinositide 3-kinase (PI3K), Akt, and mTOR abrogated LPA-induced DDR2 expression. Moreover, we observed that HIF-1α, located downstream of the mTOR, is implicated in LPA-induced DDR2 expression and ovarian cancer cell invasion. Finally, we provide evidence that LPA-induced HIF-1α expression mediates Twist1 expression to upregulate DDR2 expression. Collectively, the present study demonstrates that ATX, and thereby LPA, induces DDR2 expression through the activation of the PI3K/Akt/mTOR/HIF-1α/Twist1 signaling axes, aggravating ovarian cancer cell invasion.

ICT-based adherence monitoring in kidney transplant recipients: a randomized controlled trial.

BACKGROUND: Prior studies have explored the use of regular reminders to improve adherence among kidney transplant recipients (KTRs), but none have included real-time alarms about drug dosage, frequency, and interval. In the present study, we aimed to evaluate the efficacy and stability of an information and communication technology (ICT)-based centralized monitoring system for increasing medication adherence among Korean KTRs. METHODS: In this prospective, multicenter, randomized controlled study, enrolled KTRs were randomized to either the ICT-based centralized monitoring group or control group. The ICT-based centralized monitoring system alerted both patients and medical staff with texts and pill box alarms if there was a missed dose or a dosage/time error. We compared the two groups in terms of medication adherence and transplant outcomes over 6 months, and evaluated patient satisfaction with the ICT-based monitoring system. RESULTS: Among 114 enrolled KTRs, 57 were assigned to the ICT-based centralized monitoring group and 57 to the control group. The two groups did not significantly differ in mean adherence at each follow-up visit. The intrapatient variability of tacrolimus and mycophenolic acid levels, renal function, and adverse transplant outcomes did not differ between the intervention and control groups, or between the intervention group with feedback generation and the intervention group without feedback generation. Patients showed high overall satisfaction with the ICT-based centralized monitoring system, which significantly improved across the study period (p = 0.012). CONCLUSIONS: Due to high baseline adherence, the ICT-based centralized monitoring system did not maximize medication adherence or enhance transplant outcomes among Korean KTRs. However, patients were highly satisfied with the system. Our results suggest that the ICT-based centralized monitoring system could be successfully applied in clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03136588. Registered 20 April 2017 - Retrospectively registered.

Bioelectrical Impedance Analysis Is Not Sufficient for Determining Water Deficit in Hypernatremic Patients.

BACKGROUND Hypernatremia is associated with poor outcomes in critically ill patients, and an accurate assessment of water volume is important to determine appropriate fluid hydration. Bioelectrical impedance analysis (BIA) is a new, noninvasive, and relatively easy method for measuring hydration status. This study aimed to investigate whether bioelectrical impedance measurements of body water could reduce the frequency of blood sampling for fluid replacement in patients with hypernatremia. MATERIAL AND METHODS Fifty-one hospitalized patients were studied with hypernatremia, defined as a serum sodium ≥150 mmol/L determined by laboratory testing. Laboratory and BIA measurements were compared, and water deficiency was calculated with a conventional formula (sodium-corrected Watson formula) and measured by BIA. RESULTS The value of the absolute fluid overload (AFO) equivalent to the overhydration (OH) value, determined using BIA, did not accurately represent water deficit in patients with hypernatremia (r=0.137, P=0.347). Although the total body water (TBW) measured by BIA showed a significant correlation with that determined by the conventional formula (r=0.861, P<0.001), there was a proportional bias (r=0.617, P<0.001). The intracellular water (ICW) measured by BIA underestimated the TBW level calculated by the conventional formula by about 14.06±4.0 L in the Bland-Altman analysis. CONCLUSIONS It is not currently possible to replace blood testing with BIA for assessing volume status in hypernatremic patients. However, ICW value measured by BIA might represent plasma sodium level more accurately than extracellular water (ECW) or TBW value in patients with hypernatremia.

TGF-ß-mediated NADPH oxidase 4-dependent oxidative stress promotes colistin-induced acute kidney injury.

Background: Colistin (polymyxin E) is an important constituent of the polymyxin class of cationic polypeptide antibiotics. Intrarenal oxidative stress can contribute to colistin-induced nephrotoxicity. Nicotinamide adenine dinucleotide 3-phosphate oxidases (Noxs) are important sources of reactive oxygen species. Among the various types of Noxs, Nox4 is predominantly expressed in the kidney. Objectives: We investigated the role of Nox4 and benefit of Nox4 inhibition in colistin-induced acute kidney injury using in vivo and in vitro models. Methods: Human proximal tubular epithelial (HK-2) cells were treated with colistin with or without NOX4 knockdown, or GKT137831 (most specific Nox1/4 inhibitor). Effects of Nox4 inhibition on colistin-induced acute kidney injury model in Sprague-Dawley rats were examined. Results: Nox4 expression in HK-2 cells significantly increased following colistin exposure. SB4315432 (transforming growth factor-ß1 receptor I inhibitor) significantly inhibited Nox4 expression in HK-2 cells. Knockdown of NOX4 transcription reduced reactive oxygen species production, lowered the levels of pro-inflammatory markers (notably mitogen-activated protein kinases) implicated in colistin-induced nephrotoxicity and attenuated apoptosis by altering Bax and caspase 3/7 activity. Pretreatment with GKT137831 replicated these effects mediated by downregulation of mitogen-activated protein kinase activities. In a rat colistin-induced acute kidney injury model, administration of GKT137831 resulted in attenuated colistin-induced acute kidney injury as indicated by attenuated impairment of glomerulus function, preserved renal structures, reduced expression of 8-hydroxyguanosine and fewer apoptotic cells. Conclusions: Collectively, these findings identify Nox4 as a key source of reactive oxygen species responsible for kidney injury in colistin-induced nephrotoxicity and highlight a novel potential way to treat drug-related nephrotoxicity.

Rab25 suppresses colon cancer cell invasion through upregulating claudin­7 expression.

Ras­related protein 25 (Rab25) is a member of small GTPase and is implicated in cancer cell progression of various types of cancer. Growing evidence suggests the context­dependent role of Rab25 in cancer invasiveness. Claudin­7 is a tight junction protein and has been known to suppress cancer cell invasion. Although Rab25 was reported to repress cancer aggressiveness through recycling ß1 integrin to the plasma membrane, the detailed underlying mechanism remains to be elucidated. The present study identified the critical role of claudin­7 in Rab25­induced suppression of colon cancer invasion. 3D Matrigel system and modified Boyden chamber analysis showed that enforced expression of Rab25 attenuated colon cancer cell invasion. In addition, Rab25 inactivated epidermal growth factor receptor (EGFR) and increased E­cadherin expression. Unexpectedly, it was observed that Rab25 induces claudin­7 expression through protein stabilization. In addition, ectopic claudin­7 expression reduced EGFR activity and Snail expression as well as colon cancer cell invasion. However, silencing of claudin­7 expression reversed the tumor suppressive role of Rab25, thereby increasing colon cancer cell invasiveness. Collectively, the present data indicated that Rab25 inactivates EGFR and colon cancer cell invasion by upregulating claudin­7 expression.

Plasma presepsin for mortality prediction in patients with sepsis-associated acute kidney injury requiring continuous kidney replacement therapy.

BACKGROUND: The reliability of presepsin as a biomarker of sepsis may be reduced in patients with acute kidney injury (AKI) requiring continuous kidney replacement therapy (CKRT). This study analyzed the utility of plasma presepsin values in predicting mortality in patients with AKI requiring CKRT, particularly those with sepsis-associated AKI. METHODS: This single-center retrospective study included 57 patients who underwent CKRT, with plasma presepsin measurements, from April 2022 to March 2023; 35 had sepsis-associated AKI. The predictive values of plasma presepsin, as well as Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores, for 28-day mortality were analyzed using receiver operating characteristic curves. Multivariate Cox regression analysis was performed to identify risk factors for 28-day mortality in the sepsis-associated AKI subgroup. RESULTS: Overall, plasma presepsin showed a lower area under the curve value (0.636; 95% confidence interval [CI], 0.491-0.781) than the APACHE II (0.663; 95% CI, 0.521-0.804) and SOFA (0.731; 95% CI, 0.599-0.863) scores did. However, in sepsis-associated AKI, the area under the curve increased to 0.799 (95% CI, 0.653-0.946), which was higher than that of the APACHE II (0.638; 95% CI, 0.450-0.826) and SOFA (0.697; 95% CI, 0.519-0.875) scores. In the multivariate Cox regression analysis, a high presepsin level was an independent risk factor for 28-day mortality in sepsis-associated AKI (hazard ratio, 3.437; p = 0.03). CONCLUSION: Presepsin is a potential prognostic marker in patients with sepsis-associated AKI requiring CKRT.

Usefulness of the heart rate variability test in predicting intradialytic hypotension in patients undergoing chronic haemodialysis.

Background: Intradialytic hypotension (IDH) is the primary complication of haemodialysis (HD); however, its diverse pathophysiology and inconsistent definitions complicate its prediction. Despite attempts using the heart rate variability (HRV) test for IDH prediction, studies on its usefulness for predicting IDH diagnosed per the nadir 90 criterion are lacking. We aimed to evaluate HRV test efficacy and reproducibility in predicting IDH based on the nadir 90 criterion. Methods: Seventy patients undergoing HD participated in this multicentre prospective observational study. The HRV test was performed during non-HD periods and IDH was monitored during 12 HD sessions. IDH was diagnosed according to the nadir 90 criterion, defined as a decrease in systolic blood pressure of ≤90 mmHg during HD. After monitoring, the HRV test was repeated. An HRV-IDH index was developed using multivariate logistic regression analysis employing HRV test parameters. The predictive power of the HRV-IDH index was analysed using the area under the receiver operating characteristics curve (AUROC). Reproducibility was evaluated using correlation analysis of two HRV tests on the same patient. Results: There were 37 and 33 patients in the IDH and non-IDH groups, respectively. The HRV-IDH index predicted IDH occurrence with AUROCs of 0.776 and 0.803 for patients who had experienced at least one or repeated IDH episodes, respectively. Spearman's correlation coefficient for HRV-IDH indices was 0.859 for the first and second HRV tests. Conclusions: The HRV test holds promise for predicting IDH, particularly for patients with recurring IDH diagnosed based on the nadir 90 criterion.

Importance of dialysis specialists in early mortality in elderly hemodialysis patients: a multicenter retrospective cohort study.

The early mortality rate in elderly patients undergoing hemodialysis is more than twice that in young patients, requiring more specialized healthcare. We investigated whether the number of professional dialysis specialists affected early mortality in elderly patients undergoing hemodialysis. This multicenter retrospective cohort study analyzed data from 1860 patients aged ≥ 70 years who started hemodialysis between January 2010 and December 2017. Study regions included Seoul, Gyeonggi-do, Gangwon-do, Daejeon/Chungcheong-do, Daegu/Gyeongsangbuk-do, and Busan/Ulsan/Gyeongsangnam-do. The number of patients undergoing hemodialysis per dialysis specialist was calculated using registered data from each hemodialysis center. Early mortality was defined as death within 6 months of hemodialysis initiation. Gangwon-do (28.3%) and Seoul (14.5%) showed the highest and lowest early mortality rate, respectively. Similarly, Gangwon-do (64.6) and Seoul (43.9) had the highest and lowest number of patients per dialysis specialist, respectively. Relatively consistent results were observed for the regional rankings of early mortality rate and number of patients per dialysis specialist. Multivariate Cox regression analysis-adjusted for previously known significant risk factors-revealed that the number of patients per dialysis specialist was an independent risk factor for early mortality (hazard ratio: 1.031, p < 0.001). This study underscores the growing need for dialysis specialists for elderly hemodialysis patients in Korea.

Effects of losartan and pentoxifylline on renal dimethylarginine dimethylaminohydrolase-1 expression in proteinuric nephropathy.

BACKGROUND/AIMS: Circulatory asymmetric dimethylarginine (ADMA) is correlated with proteinuria and endothelial dysfunction in patients with proteinuric renal diseases. However, it is not known whether proteinuria itself affects expression of dimethylarginine dimethylaminohydrolase (DDAH), a degrading enzyme of ADMA, in kidney. The aim of this study is to evaluate the direct effects of losartan and/or pentoxifylline on expression of renal DDAH-1 and its relation to oxidative stress in the setting of albuminuria. METHODS: Using NRK52E cells, DDAH-1 mRNA and protein were determined after exposure to albumin with losartan and/or pentoxifylline. Reactive oxygen species (ROS), PKC activity, and NOX-4 mRNA were also measured. In addition, the effect of losartan and/or pentoxifylline on renal expression of DDAH-1 and serum ADMA were evaluated in a rat model of proteinuric nephropathy. RESULTS: Exposure to albumin resulted in increased release of N-acetyl-ß-D-glucosaminidase along with an increase of TNF-α, 8-hydroxy-2'-deoxyguanosine, and angiotensin II in NRK52E cells. Losartan and pentoxifylline reversed albumin-induced decrease of DDAH-1 mRNA and protein expression and DDAH-1 activity. The effects of losartan and pentoxifylline on DDAH-1 mRNA were associated with reduction of ROS. In addition, treatment with losartan and pentoxifylline resulted in an attenuated change of renal DDAH-1 protein expression and serum ADMA levels in vivo. CONCLUSION: DDAH-1 was positively regulated by losartan and pentoxifylline with its antioxidative effect in albumin-exposed renal proximal tubular cells. Combined treatment with losartan and pentoxifylline has a direct beneficial effect on expression of renal DDAH-1, and, thus, at least in part, modulates the circulatory levels of ADMA in proteinuric nephropathy.

Comparison of the association intensity of creatinine and cystatin C with hyperphosphatemia and hyperparathyroidism in patients with chronic kidney disease.

Herein, we compared the association intensity of estimated glomerular filtration rate (eGFR) equations using creatinine (Cr) or cystatin C (CysC) with hyperphosphatemia and secondary hyperparathyroidism occurrence, which reflect the physiological changes occurring during chronic kidney disease (CKD) progression. This study included 639 patients treated between January 2019 and February 2022. The patients were divided into low- and high-difference groups based on the median value of the difference between the Cr-based eGFR (eGFRCr) and CysC-based eGFR (eGFRCysC). Sociodemographic and laboratory factors underlying a high difference between eGFRCr and eGFRCysC were analyzed. The association intensity of eGFRCr, eGFRCysC and both Cr- and CysC-based eGFR (eGFRCr-CysC) was compared using the area under the receiver operating characteristic curve (AuROC) values for hyperphosphatemia and hyperparathyroidism occurrence in the overall cohort and the low- and high-difference groups. Age > 70 years and CKD grade 3 based on eGFRCr were significant factors affecting the high differences. eGFRCysC and eGFRCr-CysC showed higher AuROC values than that of eGFRCr, especially in the high-difference group and in patients with CKD grade 3. Our results show that CysC should be evaluated in patients with significant factors, including age > 70 years and CKD grade 3, to accurately assess kidney function to better determine the physiological changes in CKD progression and predict prognosis accurately.

A case of transient central diabetes insipidus after aorto-coronary bypass operation.

Diabetes insipidus (DI) is characterized by excessive urination and thirst. This disease results from inadequate output of antidiuretic hormone (ADH) from the pituitary gland or the absence of the normal response to ADH in the kidney. We present a case of transient central DI in a patient who underwent a cardiopulmonary bypass (CPB) for coronary artery bypass grafting (CABG). A 44-yr-old male underwent a CABG operation. An hour after the operation, the patient developed polyuria and was diagnosed with central DI. The patient responded to desmopressin and completely recovered five days after surgery. It is probable that transient cerebral ischemia resulted in the dysfunction of osmotic receptors in the hypothalamus or hypothalamus-pituitary axis during CPB. It is also possible that cardiac standstill altered the left atrial non-osmotic receptor function and suppressed ADH release. Therefore, we suggest that central DI is a possible cause of polyuria after CPB.

Lysophosphatidic acid-induced amphiregulin secretion by cancer-associated fibroblasts augments cancer cell invasion.

Cancer-associated fibroblasts (CAFs) are key structural components of the tumor microenvironment and are closely associated with tumor invasion and metastasis. Lysophosphatidic acid (LPA) is a biolipid produced extracellularly and involved in tumorigenesis and metastasis. LPA has recently been implicated in the education and transdifferentiation of normal fibroblasts (NFs) into CAFs. However, little is known about the effects of LPA on CAFs and their participation in cancer cell invasion. In the present study, we identified a critical role of LPA-induced amphiregulin (AREG) secreted from CAFs in cancer invasiveness. CAFs secrete higher amounts of AREG than NFs, and LPA induces AREG expression in CAFs to augment their invasiveness. Strikingly, knocking out the AREG gene in CAFs attenuates cancer invasiveness and metastasis. Mechanistically, LPA induces Yes-associated protein (YAP) activation and Zinc finger E-box binding homeobox 1 (Zeb1) expression through the LPAR1 and LPAR3/Gi/Rho signaling axes, leading to AREG expression. Furthermore, we provide evidence that metformin, a biguanide derivative, significantly inhibits LPA-induced AREG expression in CAFs to attenuate cancer cell invasiveness. Collectively, the present data show that LPA induces AREG expression through YAP and Zeb1 in CAFs to promote cancer cell invasiveness, with the process being inhibited by metformin, providing potential biomarkers and therapeutic avenues to interdict cancer cell invasion.

Combined impact of the inter and intra-patient variability of tacrolimus blood level on allograft outcomes in kidney transplantation.

Introduction: Tacrolimus (TAC) has been widely used as an immunosuppressant after kidney transplantation (KT); however, the combined effects of intra-patient variability (IPV) and inter-patient variability of TAC-trough level (C0) in blood remain controversial. This study aimed to determine the combined impact of TAC-IPV and TAC inter-patient variability on allograft outcomes of KT. Methods: In total, 1,080 immunologically low-risk patients who were not sensitized to donor human leukocyte antigen (HLA) were enrolled. TAC-IPV was calculated using the time-weighted coefficient variation (TWCV) of TAC-C0, and values > 30% were classified as high IPV. Concentration-to-dose ratio (CDR) was used for calculating TAC inter-patient variability, and CDR < 1.05 ng•mg/mL was classified as rapid metabolizers (RM). TWCV was calculated based on TAC-C0 up to 1 year after KT, and CDR was calculated based on TAC-C0 up to 3 months after KT. Patients were classified into four groups according to TWCV and CDR: low IPV/non-rapid metabolizer (NRM), high IPV/NRM, low IPV/RM, and high IPV/RM. Subgroup analysis was performed for pre-transplant panel reactive antibody (PRA)-positive and -negative patients (presence or absence of non-donor-specific HLA-antibodies). Allograft outcomes, including deathcensored graft loss (DCGL) and biopsy-proven allograft rejection (BPAR), were compared. Results: The incidences of DCGL, BPAR, and overall graft loss were the highest in the high-IPV/RM group. In addition, a high IPV/RM was identified as an independent risk factor for DCGL. The hazard ratio of high IPV/RM for DCGL and the incidence of active antibody-mediated rejection were considerably increased in the PRA-positive subgroup. Discussion: High IPV combined with RM (inter-patient variability) was closely related to adverse allograft outcomes, and hence, more attention must be given to pre-transplant PRA-positive patients.

Does family support mediate the effect of anxiety and depression on maternal-fetal attachment in high-risk pregnant women admitted to the maternal-fetal intensive care unit?

Purpose: This study investigated the mediating effect of family support in the relationships of anxiety and depression with maternal-fetal attachment among pregnant women admitted to the maternal-fetal intensive care unit (MFICU) in Korea. Methods: The participants were high-risk pregnant women with a gestational age of at least 20 weeks who were admitted to MFICUs in Busan and Yangsan. The Korean versions of four measurement tools were used for the self-report questionnaire: Spielberger's State-Trait Anxiety Inventory, the Edinburgh Postnatal Depression Scale, Cobb's family support measurement, and Cranley's maternal-fetal attachment scale. Data were collected from June 22 to September 20, 2020. Out of 124 participants, data from 123 respondents were analyzed. Descriptive statistics and regression analysis were done. Results: The average age of participants was 34.1 years. Their anxiety level was moderate (43.57±11.65 points out of 80) and 53.6% were identified as having moderate depression (average 10.13±5.48 points out of 30). Family support was somewhat high (average 43.30±5.03 points out of 55). The average score of maternal-fetal attachment was also somewhat high (73.37±12.14 points out of 96). Family support had a partial mediating effect in the relationships of anxiety and depression with maternal-fetal attachment among high-risk pregnant women admitted to the MFICU. Conclusion: Maintaining family support is challenging due to the nature of the MFICU. Considering the mediating effect of family support, establishing an intervention plan to strengthen family support can be helpful as a way to improve maternal-fetal attachment for high-risk pregnant women admitted to the MFICU.

Ceria-Zirconia Antioxidant Nanoparticles Attenuate Hypoxia-Induced Acute Kidney Injury by Restoring Autophagy Flux and Alleviating Mitochondrial Damage.

Oxidative stress is one of the principal causes of hypoxia-induced kidney injury. The ceria nanoparticle (CNP) is known to exhibit free radical scavenger and catalytic activities. When zirconia is attached to CNPs (CZNPs), the ceria atom tends to remain in a Ce3+ form and its efficacy as a free radical scavenger thus increases. We determined the effectiveness of CNP and CZNP antioxidant activities against hypoxia-induced acute kidney injury (AKI) and observed that these nanoparticles suppress the apoptosis of hypoxic HK-2 cells by restoring autophagy flux and alleviating mitochondrial damage. In vivo experiments revealed that CZNPs effectively attenuate hypoxia-induced AKI by preserving renal structures and glomerulus function. These nanoparticles can successfully diffuse into HK-2 cells and effectively counteract reactive oxygen species (ROS) to block hypoxia-induced AKI. This suggests that these particles represent a novel approach to controlling this condition.

Pulmonary dysfunction is possibly a marker of malnutrition and inflammation but not mortality in patients with end-stage renal disease.

BACKGROUND: Various studies have indicated that malnutrition and chronic inflammation are strong predictors of morbidity and mortality in patients with chronic kidney disease (CKD). The purpose of this study was to investigate the relationship between pulmonary function, malnutrition and chronic inflammation in patients with CKD. METHODS: One hundred and six consenting patients with CKD were enrolled in the study between 2005 and 2007. Pulmonary function was assessed by forced vital capacity (FVC), forced expiratory volume in the first second (FEV(1)) and peak expiratory flow (PEF), expressed as the normal percentage of predicted values (%FEV(1), %FVC and %PEF, respectively). Nutritional status was evaluated by skeletal muscle index (SMI), subjective global nutritional assessment (SGA), lean body mass, body mass index and serum albumin. Inflammation was assessed by the serum measurement of high-sensitive C reactive protein (hsCRP) levels. RESULTS: Malnutrition (defined as SMI > or =1) and inflammation (defined as hsCRP >2 mg/l) in ESRD patients had significant negative associations with percentage predicted values for pulmonary function tests except %PEF (SMI: %FEV(1), p = 0.009, %FVC, p = 0.001; hsCRP: %FEV(1), p = 0.025, %FVC, p = 0.022). Multivariate Cox analysis showed that the ejection fraction in echocardiography and SGA were associated with poor survival, but there was no association for %FEV(1). CONCLUSIONS: Impaired pulmonary function was associated with malnutrition and inflammation in these dialysis patients. We were not able to determine a significant relationship between pulmonary function and mortality.

NADPH oxidase 4 mediates TGF-ß1/Smad signaling pathway induced acute kidney injury in hypoxia.

Hypoxia is an important cause of acute kidney injury (AKI) in various conditions because kidneys are one of the most susceptible organs to hypoxia. In this study, we investigated whether nicotinamide adenine dinucleotide 3-phosphate (NADPH) oxidase 4 (Nox4) plays a role in hypoxia induced AKI in a cellular and animal model. Expression of Nox4 in cultured human renal proximal tubular epithelial cells (HK-2) was significantly increased by hypoxic stimulation. TGF-ß1 was endogenously secreted by hypoxic HK-2 cells. SB4315432 (a TGF-ß1 receptor I inhibitor) significantly inhibited Nox4 expression in HK-2 cells through the Smad-dependent cell signaling pathway. Silencing of Nox4 using Nox4 siRNA and pharmacologic inhibition with GKT137831 (a specific Nox1/4 inhibitor) reduced the production of ROS and attenuated the apoptotic pathway. In addition, knockdown of Nox4 increased cell survival in hypoxic HK-2 cells and pretreatment with GKT137831 reproduce these results. This study demonstrates that hypoxia induces HK-2 cell apoptosis through a signaling pathway involving TGF-ß1 via Smad pathway induction of Nox4-dependent ROS generation. In an ischemia/reperfusion rat model, pretreatment of GKT137831 attenuated ischemia/reperfusion induced acute kidney injury as indicated by preserved kidney function, attenuated renal structural damage and reduced apoptotic cells. Therapies targeting Nox4 may be effective against hypoxia-induced AKI.

Exceptional mucocutaneous manifestations with amyloid nephropathy: a case report.

BACKGROUND: Amyloidosis is a very rare disease that is difficult to diagnose because of the unspecific early clinical manifestations of the disease. Accurate and early diagnosis is extremely important because the effect of treatment is dependent on the extent of disease progression. Sicca syndrome and nail dystrophy are very rare symptoms of amyloidosis. We report here a case of sicca syndrome and nail dystrophy with renal dysfunction in a 52-year-old Korean woman who was diagnosed as having systemic amyloidosis. CASE PRESENTATION: We present the case of a 52-year-old Korean woman complaining of dry mouth and nail dystrophy for 4 months as an initial symptom. A slit lamp examination revealed superficial keratoconjunctival erosion in both eyes. A laboratory test showed anemia, azotemia, and proteinuria. Urine protein electrophoresis showed increased gamma globulin excretion. Serum free light chain of kappa and lambda were increased. Histopathological studies of biopsy specimens of minor salivary glands and kidney revealed deposits of amyloid fibrils. A bone marrow aspiration biopsy showed hypercellular marrow with 5% plasma cells. She was diagnosed as having primary systemic amyloidosis then started on chemotherapy. CONCLUSION: Such atypical mucocutaneous manifestations of amyloidosis can serve as important early diagnostic signs with less invasive biopsy confirmation in patients with systemic amyloidosis.