bluuebunny/crossref_metadata_2025 huggingface dataset:
P0852PERICYTE-SPECIFIC MANIPULATION OF HYPOXIA-INDUCIBLE FACTORS REGULATES ERYTHROPOIESIS WITHOUT AGGRAVATING RENAL FIBROSIS
Authors: Cai Pei-Zhen , PAN SZU-YU , LIN SHUEI-LIONG
Published: June 2020

Background and Aims

Stabilizers of hypoxia-inducible factor (HIF) have been shown to be effective on treatment of anemia in patients with chronic kidney disease (CKD). Increased erythropoietin (EPO) production and enhanced erythropoiesis are known to be the major mechanisms responsible for the treatment effects. However, the effect of HIF stabilization on renal fibrosis is controversial. We created animal models characterized by CKD and pericyte-specific stabilization of HIF to examine the effects of HIF on renal fibrosis and erythropoiesis.

Method

Gli1CreERT2/+;Egln1F/F, Gli1CreERT2/+;VhlF/F, and Gli1CreERT2/+;Hif1aF/F;Hif2aF/F mice were generated to study the effects of pericyte-specific overexpression or knockout of Hif. Unilateral ureteral obstruction (UUO) was used to induce CKD. The severity of fibrosis was determined by Picrosirius red stain and Col1a1 mRNA level in the kidney.

Results

Pericyte-specific stabilization of HIF resulted in increased serum EPO level, augmented splenic erythropoiesis, and polycythemia, while the severity of renal fibrosis was not affected. In line with these findings, pericyte-specific knockout of Hif1a or Hif2a did not result in significant change of renal fibrosis.

Conclusion

Our study endorses the neutral effects of pericyte-specific HIF stabilization on renal fibrosis.
P0853DECISION SUPPORT SYSTEM (DSS) FOR DIAGNOSTICS AND TREATMENT OF PATIENTS WITH CKD COMPLICATIONS
Authors: Kondratiev Egor , Novitskiy Vladimir , Galchenkov Aleksei
Published: June 2020

Background and Aims

Some of the most common complications of CKD are anemia and bone and mineral disorders (BMD). Adequacy of treatment of patients with these complications directly affects their life quality and duration.

The goal of our work is to create medical decision support system (MDSS) that will be able to generate recommendations on diagnostics and treatment of CKD patients with anemia and BMD complications, based on clinical guidelines and control the fulfillment of corresponding prescriptions.

Method

We have developed an automated medical decision support system that generates recommendations on patient’s treatment and further studies that are mandatory according to regulations, based on patient’s electronic medical record. The functionality of MDSS is based on knowledge base (KB), which consists of clinical guidelines formalized as mathematical logic operators. The system is also able to control how medical staff fulfills generated diagnostic and treatment prescriptions: deadlines, duration and order of actions, mandatory studies from regulations, drug therapy, etc.

The assessment of the system was conducted on more than 2000 CKD patients on chronic dialysis from 30 “Nefrosovet” hemodialysis clinics.

Results

MDSS was developed using process-based management principles and was successfully employed on representative sample of patients with CKD on chronic dialysis from “Nefrosovet” hemodialysis clinics. The system generated recommendations for this group of patients for the duration of 6 months. Recommendations were related to diagnostics and treatment of patients, specific diagnoses, scheduled and additional studies, drug prescriptions (where dose was set by a physician), etc.

As a result of using a system, we were able to reduce average treatment cost of patient by 14% for anemia related treatment and by 36% for BMD related treatment. At the same time the treatment quality has improved from an average of 46% to 60% of patients in target ranges of key laboratory parameters after 6 months of system usage. Treatment cost has reduced due to the timely start and gradual cancelation (by indications) of drug therapy, which also allowed us to avoid overadministration of unnecessary drugs.

Conclusion

Deployment of developed MDSS for process-based management of patients with CKD on chronic dialysis with anemia and BMD complications has shown high cost efficiency. Furthermore, automated diagnostics, therapy and prescription fullfilment control is performed without loss of quality, sometimes even with the improvement of quality of treatment process.
P0854THE ENDOGENOUS ERYTHROPOIETIN EXPRESSION IN CKD PATIENTS AT HIGH ALTITUDE: DATA FROM TIBETAN PLATEAU
Authors: Wang Yan , Dang Zonghui , Zuo Li , Zhang Lei
Published: June 2020

Background and Aims

Some studies have shown that higher altitude was associated with lower EPO doses and higher hematocrit levels in HD patients. Our pre-study also confirmed that the higher the altitude, the lower the EPO resistance index [weekly weight-adjusted dose of erythropoietin (IU/kg/week) divided by Hb concentration (g/dl)]. Possible explanations included that patients at higher altitude produce more endogenous EPO or they respond more efficiently to EPO than patients at lower altitude. The aim of this study was to determine whether endogenous EPO production was up-regulated in CKD patients at high altitude.

Method

Three cohorts from different altitude were compared. Among them, 58 CKD patients were from Tibet Autonomous Region People's Hospital (3650m above sea level, recruited between March 2019 and July 2019. The other two cohorts were from the literatures. [1,2]

The exclusion criteria included patients under EPO substitution or those with acute renal failure, polycystic kidney disease, renal carcinoma or polycythemia. The subjects were then stratified into groups according to the CKD stage. EPO concentrations were determined by using electrochemiluminescent immunoassay. Change of endogenous EPO levels with altitude by CKD stage was studied.

Results

The characteristics of the Tibet cohort were shown in table 1, the other two can be found in references. In Tibet cohort, there was a significant correlation between serum EPO concentrations and CKD stages as well as eGFR. The equation derived from liner regression analysis was EPO (mIU/ml) =-1.941*CKD stage+17.67 (r2 = 0.093, P = 0.020) and log EPO (mIU/ml) =-0.0002311*eGFR (ml/min/1.73m2) + 1.025 (r2 = 0.097, P = 0.017). Serum EPO concentrations dropped with decreasing of eGFR, see in Figure 1.

Normally there was an exponential relation between hemoglobin and endogenous EPO in healthy people. The correlation was attenuated and even absent in CKD patients. In Tibet cohort, there was no linear relation between hemoglobin and endogenous EPO (r2 < 0.001, P =0.907), see in Figure 2.

Compared with the other two cohorts at lower altitude, the average EPO concentration of Tibetan patients was higher in CKD stage one, however, it decreased quickly with increasing stages of CKD. The average EPO concentration were even lower in CKD stage two to five, see in Figure 3.

Conclusion

Endogenous EPO production was only up-regulated in patients with normal renal function at high altitude, those with impaired renal function failed to produce more EPO. Our results suggest that the possible explanation for CKD patients at high altitude had better EPO responsiveness is that they respond more efficiently to EPO other than they produce more endogenous EPO.
P0863TYPE OF PROTON PUMP INHIBITOR AND RISK OF IRON DEFICIENCY IN RENAL TRANSPLANT RECIPIENTS
Authors: M. Douwes Rianne , Vinke Joanna Sophia Jacoline , Gomes-Neto António W , Blokzijl Hans , Berger Stefan P , Bakker Stephan , De Borst Martin , Eisenga Michele Freerk
Published: June 2020

Background and Aims

Use of proton-pump inhibitors (PPIs) is common practice in renal transplant recipients (RTRs). Emerging data suggest several adverse effects of use of PPIs, including development of iron deficiency (ID). Although the latter has been shown with respect to PPIs, specific analyses for different types of PPIs and the associated risk of ID have not been performed.

Method

We used data from the TransplantLines Biobank and Cohort study, an ongoing prospective cohort study among all types of solid organ transplant recipients. For the current study, we used data from stable RTRs with a functional graft for more than 1 year post transplantation (n=795). We excluded RTRs who used any form of iron supplementation (n=54) and EPO-stimulating agents (n=24), resulting in 728 RTRs eligible for analyses. Use of PPIs was subdivided in different types of PPIs, i.e. omeprazole, esomeprazole, pantoprazole, and rabeprazole. ID was defined as TSAT<20% and ferritin <300 µg/L. Logistic regression analysis was used to assess the associations between PPIs and ID.

Results

We included 728 RTRs (age 56±13 years, 61% males), with a mean eGFR of 53±18 ml/min/1.73m2, a median [interquartile range] ferritin level of 96 (44 – 191) µg/L and mean TSAT of 24±10%. PPIs were used by 504 (69%) of the included RTRs, of which 398 (79%), 55 (11%), 49 (10%), and 2 (0.4%) respectively used omeprazole, pantoprazole, esomeprazole, and rabeprazole. Use of PPIs was strongly associated with ID (OR, 2.20; 95%CI 1.48 – 3.28; P<0.001), independent of adjustment for age, sex, BMI, eGFR, hs-CRP, smoking, alcohol use, use of calcineurine inhibitors, prednisolone, antiplatelet drugs, and antihypertensives. When subdividing the PPIs into the different types, both omeprazole (OR, 1.98; 95%CI 1.39 – 2.83; P<0.001) and esomeprazole (OR, 2.11; 95%CI 1.09 – 4.07; P=0.03) were independently associated with iron deficiency, whereas pantoprazole was not associated (OR, 0.89; 95%CI 0.47 – 1.70; P=0.73).

Conclusion

Omeprazole and esomeprazole, but not pantoprazole, are associated with an increased risk of ID. Our results are in line with previous reports that pantoprazole has the lowest potency with least increase in intragastric pH, thereby possibly interfering less with reduction of ferric to ferrous iron, and subsequently iron absorption. Future studies are warranted to confirm our present findings.
P0866EVALUATION OF ERYPTOSIS IN PATIENTS WITH CHRONIC KIDNEY DISEASE
Authors: GÖK Mehmet Gökhan , Paydas Saime , Kaya Bülent , Onan Engin , Boral Barış
Published: June 2020

Background and Aims

One of the many factors in the pathogenesis of renal anaemia, is eryptosis. The aim of this study is to evaluate eryptosis in patients with chronic renal disease stage 3-5 and 5 dialysis (5D).

Method

Patients with CKD who were monitored in our nephrology department were included in the study. The age range of the patient groups was 18-80 years and haemoglobin levels were <13 g / dl in men and <12 g / dl in women. As parameters of eryptosis, flow cytometric annexin V binding and intracellular calcium, and superoxide dismutase (SOD) activity with ELISA method were measured in 59 predialysis patient (eGFR<60 mL / min 1.73 m2), 26 haemodialysis patient, 21 peritoneal dialysis patient and 29 healthy volunteers with similar age (control). Haematological and biochemical tests including complete blood count(CBC), erythrocyte sedimentation rate (ESR), Parathormone (PTH), 25-OH vit D3, Blood urea nitrogen (BUN), Creatinine (Cr), C-reactive protein (CRP), Na, K, phosphor (P), ionized and total Calcium, Ferritin, B12 and Folate, were performed. IBM SPSS Statistics Version 20.0 was used for statistical analysis of the data

Results

The amount of intracellular calcium were 3.05 ± 1.66 in predialysis group, 2.24 ± 0.99 in haemodialysis group, 2.38 ± 0.87 in peritoneal dialysis group and 1.71 ± 0.46 in control group. For intracellular calcium there was statistically significant difference only between predialysis group and control group (p <0. 000). Annexin V binding were calculated as 1.05 ± 0.99 in predialysis group, 1.15 ± 0.56 in haemodialysis group, 1.06 ± 0.87 in peritoneal dialysis group and 0.88 ± 0.86 in control group. Comparing to control group annexin V binding in predialysis, haemodialysis and peritoneal dialysis groups, were statistically significantly increased (for all p <0.000). SOD activity was 0.07 ± 0.07 in predialysis group, 0.13 ± 0.08 in haemodialysis group, 0.14 ± 0.07 in peritoneal dialysis group and 0.03 ± 0.01 in control group. The difference between the control group and dialysis group was statistically significant (p <0. 00). Comparing to nonusers; patients using calcium channel blockers (CCB) had low annexin V binding level (p = 0.013). Patients using erythropoietin (EPO) had elevated annexin V binding level (p <0.000) and lower intracellular calcium (p = 0.014) according to non- users.

Conclusion

We determined increased eryptosis in patients with CKD stage 3-5 and 5D in our study. Inflammation and elevated parathormone were also associated with increased eryptosis. Therefore, eryptosis may be an important factor in the pathogenesis of renal anaemia. Inflammation associated CKD may increase eryptosis. In addition, this effect can be taken into consideration in the planning of treatment because of the lower incidence of eryptosis in patients using calcium channel blocker and EPO.
P0881ANEMIA SIGNIFICANTLY INCREASES RISK OF OSTEOPOROSIS IN PATIENTS WITH NON-DIALYSIS CHRONIC KIDNEY DISEASE
Authors: Lee Seonyeong , Nam Yooju , Kim Hyung Woo , Chang Jae Hyun , Yoo Tae-Hyun
Published: June 2020

Background and Aims

Anemia was frequently observed in chronic renal failure patients. The risk of osteoporosis is higher in patients with chronic anemia. Chronic anemia also showed a close relationship with bone mineral density. However, few studies have been done whether anemia affects bone mineral density with chronic kidney disease(CKD) patient. Therefore, the aim of our study is to evaluate the relationship between anemia and bone mineral density(BMD) in a large sample of non-dialysis CKD cohort.

Method

We performed an observational study in 2,089 patients who measured hemoglobin and BMD with non-dialysis CKD enrolled in the KoreaN cohort study for Outcome in patients With Chronic Kidney Disease (KNOW-CKD). Anemia was defined as hemoglobin(Hb) levels of < 13.0 g/dL for males and 12.0 g/dL for females, respectively. BMD was estimated by dual energy x-ray absorptiometry system. The observed variable was decline of BMD during follow up.

Results

The mean age was 53.6 ± 12.2 years and 1,292(61.1%) patients were males. The BMD score was positively correlated with hemoglobin levels (β, 0.007; 95% CI, 0.003-0.012; P 0.002), but inversely with prevalence of anemia (β, -0.03; 95% CI, -0.042--0.008; P 0.004). In the multivariable logistic regression model, the prevalence of osteoporosis was significantly higher in the anemia group than that in the normal hemoglobin levels (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.11-2.51, P=0.014). Among 881 patients except unavailable following BMD, 396 (19.7%) patients developed the decline of BMD during a median follow-up duration of 48 (interquartile range, 46-49) months. In the fully adjusted multivariable Cox models, risk of developing the decline of BMD was significantly higher in the anemia group (HR, 1.38; 95% CI, 1.02-1.87; P= 0.036) as compared to normal hemoglobin group.

Conclusion

We found that anemia is independently and significantly correlated with an increased risk of osteoporosis with non-dialysis CKD. Our study suggests that prompt correction of anemia in CKD patients could be beneficial to preserving bone mineral density.
P0884MYO-INOSITOL HEXAPHOSPHATE PEGYLATION IMPROVES BIOAVAILABILITY BUT REDUCES ITS ANTI-VASCULAR CALCIFICATION EFFECT IN RATS
Authors: Pérez M Mar , Ferrer Reynes Miguel David , Ortega-Castro Joaquín , Bassissi Firas , Perelló Joan , Salcedo Carolina
Published: June 2020

Background and Aims

Vascular calcification (VC) is a major contributor to increased morbidity and mortality in End Stage Kidney Disease (ESKD) patients undergoing dialysis. SNF472, a salt of inositol hexaphosphate (InsP6), is a selective calcification inhibitor that interferes in the formation and growth of ectopic hydroxyapatite (HAP). SNF472 is currently in Phase 3 clinical trials for the treatment of calciphylaxis in ESKD patients on dialysis. Inositol-1,2,3,5-tetraphosphate-4,6-bisPEG100 (InsP4bisPEG or INS3001) results from the PEGylation of inositol tetraphosphate (InsP4) with polyethylene glycol (PEG) 100. Our aim was to compare the relative bioavailability of SNF472 and InsP4bisPEG and their efficacy in the inhibition of calcification in silico, in vitro and in vivo.

Method

Subcutaneous (10 mg/kg) pharmacokinetics of InsP4bisPEG and SNF472 were assessed in Sprague Dawley (SD) rats. To evaluate the adsorption binding affinity (Eads) of SNF472, InsP4bisPEG and other inositol phosphates to the HAP crystal surface, computational studies were performed using Density Functional Theory calculations with DMOL3 (MS2016). The in vitro efficacy of the compounds was evaluated using a pharmacodynamic assay to measure the calcification potential of human plasma. An in vivo efficacy study (calcification induced by 3 consecutives daily s.c. administrations of 150 kIU/kg vitamin D3) was performed with SD rats receiving s.c. vehicle, or equimolar doses (36 µmol/kg) of SNF472 or InsP4bisPEG once daily.

Results

The PEGylation of inositol tetraphosphate in positions 4 and 6 increased the exposure and t1/2 of the compound when given subcutaneously compared to SNF472. Molecular modelling revealed that SNF472 binds to the HAP surface with higher affinity than InsP4bisPEG and INSP4 (ΔEads=-352 kcal/mol for SNF472, ΔEads=-177 kcal/mol for InsP4bisPEG and ΔEads=-146 Kcal/mol for InsP4, taking inositol as reference). These results were correlated with the inhibition of calcium phosphate crystallization in plasma in vitro. SNF472 treated animals presented significantly lower calcium levels in aorta, which were 38% and 55% lower than placebo and InsP4bisPEG treated animals, respectively.

Conclusion

The differential pharmacokinetic profile of InsP4bisPEG (INS3001) does not translate into higher, but lower, efficacy than SNF472 against vascular calcification when comparing equimolar doses.
P0885THE RELATIONSHIP BETWEEN BONE REGULATORY MARKERS AND BONE TURNOVER IN RENAL OSTEODYSTROPHY
Authors: Salam Syazrah , Gallagher Orla , Gossiel Fatma , Khwaja Arif , Eastell Richard
Published: June 2020

Background and Aims

Renal osteodystrophy is common in advanced chronic kidney disease (CKD) patients and is characterized by abnormal bone turnover and mineralization. Parathyroid hormone (PTH) increases bone turnover through osteoblast and osteoclast activation. Osteoprotegerin (OPG) is a decoy receptor of receptor activator of nuclear factor kappa-β ligand and thus, inhibits osteoclast maturation. Meanwhile, sclerostin is an inhibitor of the Wnt signalling pathway and thus, inhibits osteoblast maturation. We aimed to assess the relationship between these bone regulatory markers and bone turnover as assessed by bone histomorphometry and bone turnover markers (BTMs).

Method

We recruited 43 CKD patients with eGFR<30ml/min/1.73m2 or on dialysis. Fasting serum samples were analysed using Immunodiagnostic Systems automated assays (Boldon, UK) for intact PTH (iPTH) and BTMs such as bone alkaline phosphatase (bALP) and intact procollagen type 1 N-terminal propeptide (intact PINP) which are bone formation markers, and tartrate-resistant acid phosphatase 5b (TRAP5b) which is a bone resorption marker. OPG and sclerostin were analysed using manual ELISA by Biomedica (Vienna, Austria). Trans-iliac bone biopsy was performed after tetracycline labelling. Bone samples were analysed using quantitative histomorphometry. Normal bone turnover was defined as bone formation rate/bone surface (BFR/BS) of 18 - 38µm3/µm2/year. Spearman rank correlation was used to test the relationship between the variables.

Results

Median BFR/BS was 32.12 (IQR 17.76 – 48.25) um3/um2/year. 26% of patients had low and 40% had high bone turnover. iPTH and OPG were positively correlated with BFR/BS (rho = 0.42, p<0.01 and rho = 0.36, p<0.05 respectively). Sclerostin was not correlated with BFR/BS. Furthermore, sclerostin did not correlate with bALP and intact PINP whereas OPG correlated with TRAP5b (rho = 0.43, p<0.01). iPTH correlated with bALP (rho = 0.62, p<0.001), intact PINP (rho = 0.62, p<0.001) and TRAP5b (rho = 0.50, p = 0.001).

Conclusion

Circulating levels of iPTH and OPG were modestly associated with bone turnover but sclerostin was not. There are likely to be bone regulators other than iPTH, OPG and sclerostin which regulate bone turnover in renal osteodystrophy.
P0888FIBROBLAST GROWTH FACTOR 23 PRODUCES ARTERIAL STIFFNESS THROUGH CHANGES IN VASCULAR SMOOTH MUSCLE CELL PHENOTYPE
Authors: Muñoz-Castañeda Juan R , Rodelo-Haad Cristian , Pendon-Ruiz de Mier M Victoria , Vergara Noemi , Revilla-Gonzalez Gonzalo , Diaz-Tocados Juan Migueo , Membrives Cristina , Lopez-Baltanas Rodrigo , Soriano Cabrera Sagrario , Martin-Malo Alejandro , Ureña Juan , Santamaria Rafael , Rodriguez Mariano
Published: June 2020

Background and Aims

In patients with chronic kidney disease (CKD), high levels of c-terminal fibroblast growth factor 23 (FGF23) are associated with cardiovascular disease and mortality. Vascular smooth muscle cells (VSMC) may present two clearly differentiated functional phenotypes, contractile and synthetic. The abundance of synthetic phenotype is associated with vascular dysfunction and it is unknown whether in FGF23 may promote transition from a contractile to a synthetic phenotype in VSMC causing vascular stiffness. The present study was conducted to evaluate whether FGF23 affects VSMC phenotype and arterial stiffness.

Method and Results

High levels of FGF23 promoted VSMC transition from a contractile to a synthetic phenotype. These effects were mediated through FGFR1 and Ras/MAPK signaling activation. Inhibition of both pathways enhanced contractile phenotype of VSMC. The pro-contractile microRNAs, miR-221 and miR-222 were reduced by FGF23 and miR-221 transfection recovered the contractile phenotype of VSMC decreased by FGF23. In experimental rats, exogenous infusion of FGF23 produced an increase in vascular wall thickness with VSMC exhibiting synthetic phenotype and reduction of plasma levels of miR-221. Functional studies performed on aortic arterial rings revealed that passive and active forces were altered in rats treated with FGF23. In a group of CKD stage 2-3 patients with rather high levels of FGF23 it was observed an increased in pulse pressure reflecting vascular stiffness together with low plasma levels of miR-221 and miR-222.

Conclusion

FGF23 favors the transition of VSMC from contractile to synthetic phenotype causing vascular dysfunction and arterial stiffness; this may be a mechanism by which FGF23 contribute directly to the development of vascular disease in CKD patients.
P0897RISK FACTORS FOR AVASCULAR BONE NECROSIS IN PATIENTS WITH LUPUS NEPHRITIS
Authors: Monova Daniela , Monov Simeon , Kamenov Assen , Milenova Vladislava
Published: June 2020

Background and Aims

Avascular necrosis of bone (AVN) is an important complication of systemic lupus erythematosus (SLE) and often causes serious physical disability. The aim of this study was to investigate the risk factors for symptomatic avascular necrosis of bone (AVN) in lupus nephritis (LN) patients.

Method

The records of 374 patients (43 males, 331 females) with kidney biopsy-proven LN were reviewed retrospectively. Symptomatic AVN cases were defined as those with at least one diagnosis of AVN. The patients with LN who did not have AVN were evaluated as a control group. To determine risk factors for AVN, clinical, laboratory and therapeutic variables were analyzed by logistic regression.

Results

Symptomatic AVN was present in 17 patients (4 males, 13 females, mean age of 27,4±6,7 years). Among the 17 patients, 28 joints presented AVN. 12 occurred in hips (2 bilateral), 6-in ankles, 4-in knees, 3-in shoulders and 1- in lumbar spine. In 9 patients AVN involved 2 or more joints. 14 patients were on steroids at the time of presentation of AVN. 2 patients were not on CS and 1 patient did not has documentation of steroid use. Meta-analysis demonstrates a significant increased risk of AVN in patients with high disease activity and class IV LN (p<0,005). LN patients with AVN showed an earlier onset age (p<0,05) and received significantly higher total cumulative corticosteroid dose. AVN was not significantly associated with use of immunosuppressive agents. Serositis, coagulation disorders, vasculitis, cigarette smoking were higher incidence in male with LN and AVN. Raynaud‘s phenomenon, autoimmune thyroiditis, arthritis, Sjögren’s syndrome, IgM anticardiolipin antibodies, antiphospholipid syndrome, Cushingoid body habitus were higher incidence in female with LN and AVN.

Conclusion

Many risk factors have been involved in the development of AVN in LN patients. AVN is prevalent in class IV LN and in younger patients. Since asymptomatic osteonecrosis may remain undetected, its true prevalence could be much higher than we reported. Multifocal lesions involving more than three anatomical sites are unusual. Corticosteroids are the principal risk factor, although some cases of AVN occur in relatively steroid naïve patients. Early detection of AVN is important because the prognosis depends of the stage and location of the lesion. An individual risk assessment for AVN development should be made prior to and during treatment for LN, especially in patients high dose corticosteroids.
P0900EXPLORE THE MECHANISM OF BEAUVERICIN ON THE OSTEOBLAST CELLS
Authors: Lu Chien-Lin , Lu Kuo-Cheng
Published: June 2020

Background and Aims

In chronic kidney disease (CKD), dysregulation in mineral and bone metabolism cause abnormal bone turnover disease. Over the past years, we focus the dysregulation of osteoblast and osteoclast in CKD. Numerous evidences have shown beauvericin (BEA), a cyclic hexadepsipeptide from Codyceps cicadae, possesses anti-convulsion, anti-arrhythmia, sedation, and anti-tumor activities. The mechanism of the BEA cytotoxicity on osteoblast remains fully unclear. During bone formation and fracture healing, osteoblasts and chondrocytes undergo an orderly developmental progression that ultimately ends in apoptosis. It is still unclear what signal transduction pathways are used of beauvericin in programmed cell death in osteoblasts and its effect on bone turnover.

Method

7F2 cell line is cultured in Dulbecco’s modified eagle medium (DMEM). To induce osteoblast differentiation, a total of 1 × 105 7F2 cells were plated in a 6-cm dish containing 100 μg/mL ascorbic acid, and 10 mM β-glycerol phosphate in the absence or presence of a 0-3μM dose of Beauvericin overnight. The cytotoxic effect of BEA was first determined using the MTT method. Cell lysates were prepared by extracting proteins with lysis buffer, and western blots were developed with a peroxidase-conjugated secondary antibody, and then proteins were visualized by enhanced chemiluminescence (ECL) procedures.

Results

To clarify the rational of inhibitory effect of beauvericin on osteoblast, preosteoblast 7F2 cells were treated with 0-3μM beauvericin overnight. The extent of cell viability after 5-day culture period and observed through microscopy and MTT assay. Figure 1 showed Beauvericin can significantly decrease the number of differentiated osteoblasts in a dose dependent manner. Figure 2 in MTT assay showed the 7F2 osteoblast cells survival rate was significant reduced under beauvericin treatment, especially in high dose of beauvercin. Western blot analysis in Figure 3 showed that under 2 μM Beauvericin dose treatment, the expression of Bax protein was increased and conversely the expression of BCl-2 was decreased.

Conclusion

Taken together, we thought Beauvercin induce 7F2 osteoblast cells death and might be in a relation to apoptosis. However, the further detail mechanism is need further investigated.
P0903EFFECTS OF OSTEOPOROSIS MEDICATIONS ON BONE FRACTURE IN PATIENTS WITH CHRONIC KIDNEY DISEASE
Authors: Kao Chih-Chin , Wu Pei-Chen , Chuang Ming-Tsang , Wu Mai-Szu , Chang Tzu-Hao
Published: June 2020

Background and Aims

To evaluate the association of osteoporosis medications and outcomes of patients at risk of CKD.

Method

We included patients with stage 3-5 CKD from three Taipei Medical University-affiliated hospitals between January 1, 2011 and August 31, 2016. Patients were divided into two groups based on whether they received osteoporosis medications (bisphosphonates, raloxifene, teriparatide, or denosumab) and then matched at a 1:1 ratio by using propensity scores. The outcomes of interest were bone fractures, cardiovascular (CV) events, and all-cause mortality. Cox proportional hazard regression models were applied to identify the risk factors.

Results

A total of 39128 patients with CKD were included. After propensity score matching, 763 patients were in the study and control groups, respectively. The mean age of patients was 71.9 ± 12.5 years, and 34.4% of patients were men. After a median follow-up of 2.9 years, the incidence rates of bone fracture, CV events, and all-cause mortality were 10.4%, 7.5%, and 7.5%, respectively. Multivariate analysis results indicated that osteoporosis treatment was note associated with reduced risks of bone fracture (HR 0.85; 95% CI 0.43–1.68; P = 0.65), CV events (HR 0.82; 95% CI 0.56–1.20; P = 0.30), and all-cause mortality (HR 0.74; 95% CI 0.51–1.08; P = 0.12). Subgroup analysis demonstrated only patients with CKD stage 3 who received osteoporosis medications associated with better survival.

Conclusion

Osteoporosis medications did not reduce bone fractures, CV events or mortality in patients with CKD. Improved overall survival was observed in patients with CKD stage 3.
P0909HYPOCALCAEMIA MANAGEMENT POST PARATHYROIDECTOMY IN RENAL PATIENTS - A REVIEW OF PRACTICE
Authors: Tay Tricia , Chinnadurai Rajkumar , Chrysochou Tina , Doran Helen , Sinha Smeeta
Published: June 2020

Background and aims

Hypocalcaemia is a common post-parathyroidectomy complication in renal patients with secondary hyperparathyroidism. This is due to reduced parathormone (PTH) mediated calcium absorption in the kidneys and increased influx of calcium to bones. Our initial study in January 2015 showed preloading patients with one alfacalcidol 2 microgram once a day for 5 days preoperatively was ineffective in reducing hypocalcaemia related complications. We re-investigated the outcomes in patients following a change in practice to use one alfacalcidol 5 microgram once a day for 5 days preoperatively.

Method

All patients with pre-existing chronic kidney disease (CKD) who underwent parathyroidectomy by a single surgeon in our centre between March 2016 and October 2017 were included (12 patients). The outcomes (length of hospital stay and hypocalcaemia requiring IV calcium replacements) were compared with a previous study on patients operated on by the same surgeon between April 2008 and September 2014 (24 patients). Statistical analysis was conducted using Microsoft excel and SPSS version-22.

Results

Twelve patients were included in this study; 5 were females. Mean age at surgery was 54 (range 45-61) years. Eight patients were on long-term haemodialysis, 3 had a functioning renal transplant and 1 had CKD stage 5. Eight patients had been receiving cinacalcet for more than one month preoperatively.

Mean length of stay (LoS) was 5.3 days (range 3-10), half (n=6) were discharged four days post-op. Ten had a total parathyroidectomy, of which half (n=5) were discharged after post-op day 4. Four patients were not preloaded with 5mcg as per protocol; reasons for non-adherence to the protocol included regular prescription of alfacalcidol and physician discretion to utilise a lower dose. Patients with lower pre-op corrected calcium levels (2.4-2.6 mg/dL) stayed for a mean of 6.74 days after surgery. This was a longer LoS compared to other calcium ranges. No hypercalcemia related complications were recorded. The need for post-operative intravenous calcium use decreased from 10/24 to 2/12. Despite more patients having total parathyroidectomy and being on dialysis, a smaller proportion required IV calcium in the post-operative phase, although this was not statistically significant due to the small sample size (p=0.26).

Conclusion

Our study highlights that the current practice of preloading one alphacalcidol 5 mcg once a day for 5 days preoperatively in renal patients undergoing parathyroidectomy appears to be a safe and effective approach. Ongoing monitoring and further studies on a larger cohort of patients is needed to strengthen these observations.
P0912THE SERUM CREATININE TO CYSTATIN C RATIO AND CLINICAL OUTCOMES IN PATIENTS WITH NON-DIALYSIS CHRONIC KIDNEY DISEASE: THE KNOW-CKD COHORT
Authors: Lee Kyu-Beck , Hyun Young Youl , Oh Kook-Hwan , Ahn Curie
Published: June 2020

Background and Aims

Muscle wasting leads to poor outcomes in patient with chronic kidney disease (CKD). The serum creatinine to cystatin C (Cr/CysC) ratio has been reported as marker for muscle mass and may predict outcomes in chronic diseases. We hypothesized that the Cr/CysC ratio would be a predictor of outcomes in CKD.

Method

We investigated a total of 2142 patients (male 61%, aged 54±12 year) with CKD followed for a median of 3.74 years. We assessed the factors associated with Cr/CysC ratio and the relationship between Cr/CysC ratio and outcomes of end-stage renal disease (ESRD), cardiovascular event (CVE), and mortality.

Results

The Cr/CysC ratio significantly correlated with age (r=-0.18), estimated glomerular filtration rate (eGFR) (r=-0.21), serum albumin (r=0.11), 24-hour urine creatinine (r=0.38), and moderate to vigorous physical activity time (r=0.07). After adjusting for age, sex, eGFR, and log urine albumin creatinine ratio (model 1), the hazard ratios for ESRD, CVE, and mortality were 0.96 (95% CI, 0.86-1.07), 0.78 (95% CI, 0.61-0.99), and 0.72 (95% CI, 0.53-0.97) per 1 standard deviation Cr/CysC increase (0.21), respectively. After full adjustment for model 1 variables plus lifestyle factors, laboratory factors, and comorbidities (model 2), the hazard ratios for ESRD, CVE, and mortality were 0.99 (95% CI, 0.88-1.10), 0.84 (95% CI, 0.65-1.07), and 0.75 (95% CI, 0.55-0.99) per 1 standard deviation Cr/CysC increase (0.24), respectively. In subgroup of the elderly (age>65 year) and early stage CKD (eGFR>60 ml/min/1.73m2), the hazard ratios for CVE were significantly lower in patients with high Cr/CysC ratio.

Conclusion

Cr/CysC ratio correlates with muscle biomarkers and physical activity. A higher Cr/CysC ratio is associated with low CVE and mortality, but not ESRD in CKD.
P0912AKIDNEY AGING CONSTITUTES INFLAMMATORY PROCESS THAT CONTRIBUTES TO EXACERBATION OF KIDNEY INJURY
Authors: Jung Su Woong , Moon Ju-Young , Kim Yang-Gyun , Jeong Kyung Hwan , Lee Sang-Ho
Published: June 2020

Background and Aims

Aging is a natural process accompanied by decline of regenerative potential. Some argue that aging process is just an irreversible physiologic process, whereas some advocate that it should be viewed as disease.

Method

To determine the nature of kidney aging and kidney disease at transcriptional level, whole kidney RNA sequencing was performed on young (2-month-old), middle-aged (12-month-old), and old (24-month-old) mice and young mice with adenine-induced nephropathy. In addition, young and old mice were fed with either standard or adenine-enriched diet for 4 weeks, and then the degree of renal injury was compared.

Results

The transcript profile of the old kidneys was mostly involved in inflammation and activation of innate and adaptive immune system and almost same to the transcript alterations of adenine-induced nephropathy. The genes implicated in fibrosis were downregulated until middle-age period, and then upregulated with the advance of age. The old kidneys showed augmented inflammatory response in a model of adenine-induced nephropathy compared with young kidneys, leading to more widespread fibrosis.

Conclusion

These findings showed that the pathophysiologic process of kidney aging and adenine-induced kidney injury shows similar natures in the context of inflammation and immune response. When kidney injury is superimposed on the aged kidneys, age-related inflammation potentiates inflammatory response and results in increased renal damage.
P0914NEUTROPHIL EXTRACELLULAR TRAPS FORMATION IN HEMODIALYSIS PATIENTS
Authors: Litmanovich Adi , Khazim Khaled , Hassan Kamal , Kristal Batya
Published: June 2020

Background and Aims

Hemodialysis (HD) patients suffer from devastatingly high rates of morbidity and mortality due to infections. Neutrophils isolated from HD patients were shown in the past to exhibit impaired phagocytosis in a mechanism yet to be completely elucidated. In 2004, Brinkmann et al. were the first to describe a new form of cell death which they termed Neutrophil Extracellular Trap Formation, or NETosis, in which neutrophils expulse batches of DNA and proteins in response to bacterial or chemical stimuli in order to trap and remove the stimulus. NETosis is further divided into two pathways, NADPH oxidase (NOX)-dependent and NOX-independent, induced in vitro by phorbol 12-myristate 13-acetate (PMA) and Calcium Ionophore (CI), respectively. In this research, we aim to assess the capacities of HD neutrophils to engage in NETosis, hypothesizing they might be diminished similarly to their phagocytic capacities, and to elucidate the underlying mechanism behind this impairment.

Method

Neutrophils were isolated from whole venous blood of normal controls and from the arterial line of HD patients before the onset of a dialysis session using EasySepTM direct human neutrophils isolation kit. Then, NETosis was induced with either PMA, Calcium Ionophore A23187 or Phosphate-buffered saline (PBS) as negative control. cfDNA released from the cells was quantified by measuring SYTOXTM-green nucleic acid stain fluorescence levels in the supernatant after stimulation using Elisa plate reader and morphological analysis was done under fluorescence microscope. Reactive oxygen species levels were quantified using flow cytometry and superoxide dismutase (SOD) activity was measured using the SOD Assay Kit (Sigma-Aldrich). Protein arginine deiminase 4 (PAD4) expression was assessed by western blotting. Hydrogen peroxide (H2O2) was added exogenously in order to restore NETosis.

Results

HD isolated neutrophils exhibit decreased NETosis compared with normal controls in response to both PMA in the NOX-dependent pathway and CI in the NOX-independent pathway, as measured by immunofluorescence and cfDNA quantification. In the NOX-dependent pathway SOD activity was found to be 14% decreased in HD patients, resulting in the accumulation of superoxide radicals and decreased production of H2O2. In the NOX-independent pathway, PAD4 expression was found to be significantly decreased as well. NET formation was restored in vitro in HD neutrophils by the addition of exogenous H2O2.

Conclusion

To date, impaired NETosis was described only in congenital conditions such as chronic granulomatous disease and myeloperoxidase deficiency. To our knowledge, our research is the first to describe an acquired defect in NETosis in end stage renal disease patients undergoing chronic hemodialysis. An intervention aimed to improve neutrophil function in these patients may reduce the morbidity and mortality due to infection-related disease.
P0921ROLE OF UREMIC TOXIN, INDOXYL SULFATE IN SARCOPENIA OF NONDIALYSIS DEPENDENT-CHRONIC KIDNEY DISEASE PATIENTS
Authors: Kim Jun Chul , Kang Seok Hui , Han Miyeun , Kim Su-Hyun , Cha Ran-Hui , An Won Suk , Do Jun Young
Published: June 2020

Background and Aims

Sarcopenia in patients with chronic kidney disease (CKD) is highly prevalent and leads to high rate of morbidity and mortality. The role of indoxyl sulfate (IS) to develop muscle wasting has been researched and proved in several animal model studies. However, there is no human data showing this relationship in CKD population. The aim of the present study was to evaluate the association between serum IS levels and each component of sarcopenia in nondialysis dependent-CKD (NDD-CKD) patients.

Method

We enrolled 150 NDD-CKD adult patients from 6 medical centers and collected data of demographics, blood chemistry such as indoxyl sulfate, interleukin (IL)-6, and estimated glomerular filtration rate using MDRD equation (eGFR), and body mass index (BMI, kg/m2). We also measured hand-grip strength (HGS, kg), walking speed (WS, m/s), skeletal muscle mass (SMM, kg) by bioelectrical impedance analysis (BIA).

Results

The numbers of male sex was 97 (64.7%). Mean age was 63.7±10.8 years old. The numbers of patients with diabetes mellitus was 77 (52.0%). Charlson comorbidity index (CCI) score was 3.9 ± 1.9. The stage of CKD ranged from 3 to 5 (eGFR=33.7±12.0 ml/min/1.73m2, mean±SD). Correlation coefficients with indoxyl sulfate levels were 0.211 for serum IL-6 level (P = 0.010), -0.212 for HGS (P = 0.009), -0.188 for WS (P = 0.021), -0.237 for SMM (P = 0.004), and -0.168 for BMI (P = 0.041), respectively. Correlation analysis showed that indoxyl sulfate levels had inverse association significantly with HGS, WS, SMM, and BMI and were positively associated with serum IL-6 levels.

Conclusion

Our study shows that higher serum indoxyl sulfate level was significantly associated with lower levels of muscle mass, strength, and physical performance function and higher inflammation status in non-dialysis dependent CKD patients. We suggest that the role of AST120 in prevention or treatment of sarcopenia be studied in this CKD population.
P0922A LOW AROMATIC AMINO-ACID DIET IMPROVES RENAL FUNCTION AND PREVENTS KIDNEY FIBROSIS IN MICE WITH CHRONIC KIDNEY DISEASE
Authors: Barba Christophe , Soulage Christophe , Glorieux Griet , PICARD Cecile , Fouque Denis , Koppe Laetitia
Published: June 2020

Background and Aims

Despite decades of use of low protein diets (LPD) in the management of chronic kidney disease (CKD), the mechanisms through which it delays the progression to end-stage renal disease (ESRD) remain controversial. A reduced production of uremic toxins could contribute to the benefits of the LPD. Aromatic amino-acids are precursors of major uremic toxins such as p-cresyl sulfate (PCS), indoxyl sulfate (IS), indole-3-acetic acid or phenol. We investigated the hypothesis that a low aromatic amino acid diet (LAA, namely low intake of tyrosine, tryptophan and phenylalanine) while being normoproteic, could be as effective as a LPD, through the specific diminution of uremic toxins production.

Method

Renal failure was chemically induced in mice with a diet containing 0.25% (w/w) of adenine. Thereafter, they received 3 different diets for 6 weeks: normoproteic diet (NPD: 14.7% proteins, aromatics 0.019%), LPD (5% proteins, aromatics 0.007%) and LAA (14% proteins, aromatics 0.007%).

Results

LAA and LPD had no significant effect on body weight. Plasma creatinine was significantly lower in LPD and LAA groups compared to NPD group (72 ± 4 and 73 ± 4 µmol/L vs 127 ± 6 µmol/L, p<0.0001), as well as proteinuria (1.3 ± 0.3 and 1.2 ± 0.1 mg/24h vs 3.8 ± 0.9 mg/24h, p<0.05). Kidney fibrosis was more severe in NPD group vs LPD and LAA groups (17 ± 1% vs 10 ± 1 % and 13 ± 2 %, p<0.0001 and p=0.01). Kidney inflammation was also reduced with LPD and LAA. Free PCS and IS were lower in LPD and LAA groups compared to NPD group.

Conclusion

These results suggest that LAA confers similar benefits as compared with those of LPD to delay the progression of CKD through reduction of uremic toxins production, with lower risk of malnutrition.

Renal function and urinary protein excretion in control and CKD mice Serum creatinine (A), blood urea nitrogen (B) and urinary proteins (C) in control and CKD mice fed with normoproteic diet (NPD), low protein diet (LPD) or low aromatic amino-acid diet (LAA). Data are expressed as mean ± SEM for n = 5-11 animals in each group.

*p < 0.05, **p < 0.01, ***p < 0.001 vs CKD-NPD; (two-way ANOVA and Dunnett post hoc test).
P0924IMMUNE DISTURBANCES INDUCED BY HYPERVOLEMIA DO NOT ACTIVATE THE NLRP3 INFLAMMASOME IN HAEMODIALYSIS PATIENTS
Authors: Ulrich Christof , Wilke Annegret , Schleicher Nadja , Girndt Matthias , Fiedler Roman
Published: June 2020

Background and Aims

Hypervolemia is frequent in haemodialysis (HD) patients and is linked to inflammation, which may be further enhanced by endotoxemia. The impact of hypervolemia on immune cells i.e. a main monocytic defence mechanism - the NLRP3 inflammasome, has not been studied in detail. Therefore, we hypothesized that endotoxinemia putatively present in hyper- but normovolemic patients can trigger the activation of caspase-1 and thus increasing IL-1ß secretion.

Method

45 HD patients were included in the observational study, measuring immune parameters (cell counts, caspase-1, oxidative stress, cytokine gene expression and serum analysis (IL-1ß) at two time points (directly after dialysis BS1) and three days later after the long dialysis free interval (BS2). Fluid status was evaluated by electrical bioimpedance vector analysis, defining hypervolemia (H) as >75 vector percentile. Data collected after the long dialysis interval is presented in this paper.

Results

Seventeen patients were classified as hyper-(H-HD), 19 as normovolemic (N-HD), 9 failed to meet the inclusion criteria. Monocytes were elevated and lymphocytes decreased by hypervolemia. Oxidative stress was slightly elevated in H-HD. However, neither caspase-1 frequency (H: 77.9±4.2% vs. 79.2±6.9%, p=0.916) nor caspase-1 expression (MFI, H: 42.8±13.3 vs. 43.6±17.1, p=0.880) were different. In vitro stimulation of PBMC’s by specific NLRP3 inflammasome stimulation significantly increased caspase activity in both cohorts to the same extent (89.9±22.6 vs. 88.0±23.3, p=0.900). As a result of it both IL-1ß mRNA expression (1.7±1.9 vs N: 1.1±0.8, 0.306) and serum IL-1ß (pg/ml) did not differ between the groups (H: 1.99±0.2 vs. N: 1.98±0.6, p<0.135).

Conclusion

The NLRP3 inflammasome is not activated thus refuting the hypothesis that endotoxemia is a main driver for inflammation in H-HD.