FC 091URINARY CCL5 MRNA, A POTENTIAL BIOMARKER FOR PROGRESSION OF TYPE 2 DIABETIC NEPHROPATHY

Background and Aims In recent years, it has been found that targeted mRNA detection of sediment cells in urine can be used as novel biomarkers for the diagnosis of diabetic nephropathy (DN). However, its value in predicting the progression of DN is not clear. The purpose of this study is to seek for urinary mRNA markers that evaluate the prognosis of DN through systems biological screening, clinical verification and prospective studies. Method GEO database and “Nephroseq” platform were searched, and the transcriptome data of DN glomeruli and tubules and their clinical information were obtained. Weighted gene co-expression network analysis (WGCNA) combined with gene ontology (GO) annotation and KEGG pathway enrichment analysis were used to screen the hub genes negatively related to eGFR, and the hub genes were used as candidate markers for mRNA detection in urine sediment in DN patients. A total of 91 patients with DN diagnosed by renal biopsy were included, and 60 patients with type 2 diabetes and 61 healthy people were selected as the control groups. The mRNA expression of candidate molecules was detected by Taqman probe quantitative PCR, and the correlation between mRNA expression and eGFR and urinary protein levels were analyzed. Patients with DN were followed up for a median time of 21 months, and the primary end point was defied as end stage renal disease or eGFR decreasing by more than 50%. Multivariate Cox regression was used to evaluate the value of mRNA in predicting DN progression. Results GSE30528 and GSE30529 datasets were selected for analysis, including mRNA expression data of 9 cases of DN and 13 cases of normal glomeruli; and 10 cases of DN and 12 cases of normal tubules respectively. The clinical data of the patients in this study, including gender, race, age and eGFR, were searched on the Nephroseq platform. The gene modules negatively related to eGFR were screened by WGCNA. GO and KEGG analysis showed that the main function of the gene modules in both datasets were related to the activation of inflammatory cells and chemokines pathway. Through the screening of hub genes and the comparison of expression levels, CCL5, CXCL1, CXCL6 and CXCL12 were finally obtained as candidate genes. Quantitative PCR showed that the levels of CCL5 and CXCL1 was significantly increased in DN group, CCL5 was negatively correlated with eGFR and positively correlated with urinary protein level, while CXCL1 was negatively correlated with eGFR, but had no significant correlation with urinary protein level. Multivariate Cox regression showed that eGFR, urinary protein level, degree of renal fibrosis and urinary CCL5 were independent risk factors of primary end point. Conclusion The activation of chemokine signal pathway in renal tissue is involved in the progression of DN. Urinary CCL5 mRNA can independently predict the prognosis of DN and may be served as a novel biomarker for the progression of DN.

Interpretation of 24-Hour Urinary Protein Level for Diagnosis of Nephrotic Syndrome in Marked Hypoalbuminemia

Nephrotic syndrome is a common renal problem in childhood and is characterised by generalised oedema, massive proteinuria, hypoalbuminemia and hyperlipidemia. There are various laboratory methods to quantify proteinuria. Among them 24-hour urinary protein estimation is considered a gold standard for diagnosis of nephrotic syndrome. Nephrotic range proteinuria is considered when 24-hour urinary protein is more than 40 mg/m2/hr. There is scarce literature available regarding the changes in quantitative proteinuria when there is marked hypoalbuminemia (serum albumin less than 2.5 gm/dL). This series is about three patients of nephrotic syndrome (6 yers old male, 4 years old male and 5 years old male), having marked hypoalbuminemia and their 24-hour urinary protein level resulted into non-nephrotic range. All the patients underwent relevant physical, clinical examinations and laboratory blood and urine investigations(Haemoglobin, Mantoux test, chest x-ray, urine routine, urine culture and sensitivity, lipid profile, serum albumin and 24 hour urinary protein). All the cases were managed with Prednisolone and diuretics like Furosemide and were followed up till the subside of proteinuria and oedema conditions.

Sodium Thiosulfate Ameliorates Renovascular Hypertension-Induced Renal Dysfunction and Injury in Rats

Background/Aims: Arterial stenosis activates the renin-angiotensin-aldosterone system subsequently resulting in renovascular hypertension (RVHT) and renal oxidative injury. We explored the effect of sodium thiosulfate (STS, Na2S2O3), a developed antioxidant in clinical trial, on RVHT-induced hypertension and renal oxidative injury in rats. Methods: We induced RVHT in male Wistar rats with bilaterally partial ligation of renal arteries in the 2-kidney 2-clip model. We evaluated the STS effect on RVHT-induced oxidative injury and apoptosis by a chemiluminescence amplification method, Western blot, and immunohistochemistry. Results: We found STS displayed a dose-dependent antioxidant H2O2 activity and adapted the maximal scavenging H2O2 activity of STS at the dosage of 0.1 g/kg intraperitoneally 3 times/week for 4 weeks in RVHT rats. RVHT induced a significant elevation of arterial blood pressure, blood reactive oxygen species amount, neutrophil infiltration, 4-HNE and NADPH oxidase gp91 expression, Bax/Bcl-2/poly(ADP-ribose) polymerase (PARP)-mediated apoptosis formation, blue Masson-stained fibrosis, and urinary protein level. STS treatment significantly reduced hypertension, oxidative stress, neutrophil infiltration, fibrosis, and Bax/Bcl-2/PARP-mediated apoptosis formation and depressed the urinary protein level in the RVHT models. Conclusion: Our results suggest that STS treatment could ameliorate RVHT hypertension and renal oxidative injury through antioxidant, antifibrotic, and antiapoptotic mechanisms.

Chronic treatment with the (iso-)glutaminyl cyclase inhibitor PQ529 is a novel and effective approach for glomerulonephritis in chronic kidney disease

Glomeruli and renal tubule injury in chronic kidney disease (CKD) is reported to involve induction of macrophage activation through the CCL2/CCR2 axis. The effects of inhibitors of the CCL2/CCR2 axis, such as anti-CCL2 antibody and CCR2 antagonist, on kidney function in animal models or humans with kidney dysfunction have been demonstrated. The N-terminal glutamine on immature CCL2 is replaced with pyroglutamate (pE) by glutaminyl cyclase (QC) and isoQC. pE-CCL2 is stable and resistant to peptidases. We hypothesized that inhibiting QC/isoQC activity would lead to the degradation of CCL2, thereby ameliorating CKD and reducing kidney inflammation. To test this hypothesis, we investigated the renoprotective properties of the QC/isoQC inhibitor PQ529 in anti-glomerular basement membrane (GBM) antibody–induced glomerulonephritis Wistar Kyoto (WKY) rats. Three-week repeated administration of PQ529 (30 and 100 mg/kg, twice daily) significantly reduced the serum and urine CCL2 and urinary protein excretion in a dose-dependent manner. Correlations between the urinary protein level and serum or urinary CCL2 levels were confirmed in tested animals. Repeated administration of PQ529 significantly reduced the expression of CD68, a macrophage marker, in the kidney cortex and mononuclear infiltration into the tubulointerstitium. In addition, decreased levels of urinary KIM-1, β2 microglobulin, and clusterin were detected, suggesting the inhibition of inflammation in both the proximal and distal tubules. These results suggest that PQ529 suppresses the progression of inflammation-induced renal dysfunction by inhibiting the CCL2/CCR2 axis. Inhibition of QC/isoQC may thus be a viable alternative therapeutic approach for treating glomerulonephritis and CKD patients.

A case of minimal change disease after the administration of anti receptor activator of nuclear factor kappa B ligand (RANKL) monoclonal antibody: a case report

Background Minimal change disease (MCD) is one of the causes of idiopathic nephrotic syndrome in adults. The pathogenesis of proteinuria in MCD has not been fully understood. Recently, it has been reported that the receptor activator of nuclear factor-kappa B (RANK)/RANK ligand (RANKL) may contribute to the podocyte biology in kidney diseases. Denosumab is a human anti-RANKL monoclonal antibody used to treat osteoporosis. Here we report a case of MCD after denosumab administration. Case presentation A 59-year-old male without any episodes of proteinuria was given denosumab to treat osteoporosis. Two weeks after its administration, he noticed a foamy urine and bilateral pretibial edema. Laboratory tests revealed that he had severe proteinuria (15g/g Cr), hypoproteinemia (4.0g/dL), and hypoalbuminemia (1.5g/dL). Based on the results, he was diagnosed with nephrotic syndrome. The proteinuria selectivity index was 0.05, indicating selective proteinuria. Renal biopsy showed minor glomerular abnormality with less tubulointerstitial damage, and electron microscopy showed extensive foot process effacement, indicating MCD. With all these results, glucocorticoid therapy of 50mg/day prednisolone was started. After 4weeks of treatment, the urinary protein level remains high (3.1g/g Cr). Prednisolone therapy was continued, and the levels of proteinuria decreased gradually to the range of partial remission (1.2g/g Cr) with another 7weeks of prednisolone treatment, but complete remission was not achieved. Conclusions This might be a case wherein RANKL inhibition is associated with the pathogenesis of MCD. Further studies will be needed to elucidate the causal relationship of RANK-RANKL signaling to the pathogenesis of MCD.

P0504FACTORS ASSOCIATED WITH THE LONG-TERM RENAL OUTCOME OF IDIOPATHIC FOCAL SEGMENTAL GLOMERULOSCLEROSIS WITH NEPHROTIC SYNDROME

Background and Aims In the treatment of idiopathic focal segmental glomerulosclerosis (FSGS) with nephrotic syndrome, the remission of proteinuria is considered to be an important goal. The partial remission of proteinuria improves renal survival, whereas it may progressively reduce the renal function. A study searched for a novel partial remission more accurately reflecting the long-term renal outcome. The goal of proteinuria reduction for improving the renal prognosis remains to be clarified. We examined factors associated with the long-term renal outcome of idiopathic FSGS. Method Of 148 patients with FSGS diagnosed based on kidney biopsy between 1981 and 2018, a retrospective cohort study was conducted involving 33 who had undergone immunosuppressive therapy for nephrotic syndrome, and had been followed-up for ≥1 year, excluding those with secondary FSGS. We examined the renal prognosis, regarding a 50% decrease in the estimated glomerular filtration rate (eGFR) as an outcome. We calculated the rate of decrease in the urinary protein level 4 and 8 months after the start of treatment, and estimated the rate of decrease associated with renal hypofunction using ROC analysis. Based on the results of ROC analysis, Cox’s proportional hazard analysis was performed using factors contributing to renal hypofunction as covariates. Results Concerning the background of the 33 patients, the mean follow-up period was 11.4 years, and there were 24 males. The mean age was 49.8 years, and the mean blood pressure was 100.5 mmHg. The mean urinary protein level, albumin (Alb) level, eGFR, and total cholesterol (TCho) level were 7.4 g/day, 2.1 g/dL, 44.3 mL/min/1.73 m2, and 369 mg/dL, respectively. Corticosteroid therapy was selected in 21 patients, whereas it was combined with steroid pulse therapy in 12. The daily dose of prednisolone was 37.3 mg. On ROC analysis, the rate of decrease in the urinary protein level after 4 months was 83.1% (AUC: 0.74, sensitivity: 0.80, specificity: 0.74), and that after 8 months was 85.7% (AUC: 0.78, sensitivity: 0.90, specificity: 0.65). Cox’s proportional hazard analysis, in which the data were adjusted with the sex, blood pressure, urinary protein level at the start of treatment, Alb level, eGFR, and treatment methods, showed that the rate of decrease in the urinary protein level after 4 months was significantly correlated with renal hypofunction: after 4 months: hazard ratio, 0.19 (95%CI: 0.04-0.77); p=0.0202; after 8 months: hazard ratio, 0.34 (95%CI: 0.05-1.37); p=0.1359. Conclusion In the treatment of idiopathic FSGS with nephrotic syndrome, the rate of decrease in the urinary protein level 4 months after the start of treatment was correlated with the long-term renal outcome.

Association between Sarcopenia and Renal Function in Patients with Diabetes: A Systematic Review and Meta-Analysis

Previous studies involving patients with diabetes have indicated that sarcopenia is related to renal function. The objective of the present study was to investigate the association between sarcopenia and urinary albumin level, urinary protein level, and estimated glomerular filtration rate (eGFR) in patients with diabetes. A meta-analysis of observational studies was conducted. A literature search was performed using MEDLINE, Cochrane Controlled Trials Registry, and ClinicalTrials.gov. Data were extracted from studies investigating the association between sarcopenia and urinary albumin level, urinary protein level, and eGFR and by calculating odds ratio (OR) and 95% confidence intervals (CIs). Statistical analysis was performed using a random-effects model to calculate pooled OR and 95% CI. Six studies (2662 patients) that met the criteria were included in the meta-analysis. Sarcopenia was significantly associated with urinary albumin level with a pooled OR of 2.11 (95% CI, 1.55–2.88; P<0.001). The pooled ORs of the associations between sarcopenia and urinary protein level and decreased eGFR were 1.82 (95% CI, 1.13–2.92; P=0.01) and 3.75 (95% CI, 1.24–11.41), respectively. Sarcopenia was significantly associated with urinary albumin level, urinary protein level, and decreased eGFR. However, further investigations are needed, including meta-analyses with a larger number of studies.

Membranous nephropathy associated with thrombospondin type-1 domain-containing 7A (THSD7A) in an adult woman with eosinophilia

A 30-year-old woman on steroid therapy for eosinophilia presented with nephrotic syndrome during steroid tapering. She was diagnosed with membranous nephropathy (MN) stage II–III (positive for IgG1 and IgG4) by renal biopsy. There was no evidence of secondary MN. Her urinary protein level was controlled to 0.5 g/day or less, and her eosinophil count in white blood cell differential was stabilized at less than 10% without increasing the steroid dosage. The renal specimen did not show any enhanced granular expression of PLA2R along the glomerular basement membrane, and PLA2R was not detected in the patient’s serum. On retrospective analysis, enhanced granular staining for thrombospondin type-1 domain-containing 7A (THSD7A) in the glomeruli was detected in the biopsy, and anti-THSD7A IgG was detected in the serum using a commercial indirect immunofluorescence test (IFT). Based on these, the case was considered as THSD7A-associated MN with comorbid eosinophilia. The causal relationship between THSD7A-related MN and eosinophilia was unclear. However, a few cases of THSD7A-associated MN with eosinophilia have been reported, and further clarification on the relationship between THSD7A-related MN and eosinophilia is warranted.

Mechanism Underlying Selective Albuminuria in Minimal Change Nephrotic Syndrome

As water and solutes are filtered through the slit membrane, it is an a priori concept that a slit membrane is an essential filtration barrier for proteins, including albumin. However, in cases of minimal change nephrotic syndrome, the number of slit membranes is reduced by the foot process effacement and tight junction-like cell adhesion. Furthermore, albumin endocytosis is enhanced in the podocytes under condition of minimal change disease, and albumin is selectively transported by the albumin receptor FcRn. Suppressing the endocytosis of albumin with anti-FcRn antibody decreases the urinary protein level. The expression of motor molecules, such as cytoplasmic dynein 1 and myosin IX, is increased in the podocytes under conditions of minimal change nephrotic syndrome, suggesting the enhanced transport of vesicles containing albumin. Podocyte vesicle transport may play an important role in the pathology of selective albuminuria in cases of nephrotic syndrome.

Association of serum hydrogen sulphide with hypertension and proteinuria in pre-eclampsia

Background: Preeclampsia is a hypertensive disorder of pregnancy affecting multiple systems and characterized chiefly by hypertension and proteinuria in a previously normotensive and non proteinuric women. The main underlying cause for its pathophysiology is an imbalance between the physiological vasoconstrictor and vasodilator molecules in circulation leading to maternal endothelial dysfunction. Hydrogen sulphide (H2S) is a physiological vasodilatory gasotransmitter which plays an important role in the development of hypertension and proteinuria in preeclampsia. Aims and Objectives: The aim of this study was to determine the serum level of hydrogen sulphide and spot urinary protein levels in preeclampsia cases and compare it with age matched controls which were normal pregnant women and to find any correlation, if exists, between these two parameters. Materials and Methods: Serum level of H2S and spot urinary protein level were measured in one hundred pregnant women with preeclampsia and the values were compared with age matched controls. Results: The mean serum H2S level was 32.31 ± 12.62μmol/L in patients which was significantly lower (p<0.001) when compared to controls where mean was 114.50 ±20.35μmol/L. The mean spot urinary protein level was found to be 11.83 ± 5.06 mg/dl in preeclampsia cases which was significantly higher (p<0.001) than in controls where it was 7.18 ± 2.38 mg/dl. A negative correlation was found between the serum level of H2S and both the systolic BP (r=-0.725, p<0.001) and diastolic BP (r= - 0.639, p<0.001) in preeclampsia patients.A negative correlation was also observed between the serum levels of H2S and spot urinary protein in preeclampsia (r=-0.541, p<0.001). Conclusion: The present study has elucidated that the serum levels of hydrogen sulphide decreases and the spot urinary protein levels increases in preeclampsia when compared to normal pregnant women and hydrogen sulphide shows a negative correlation with both systolic and diastolic BP in preeclampsia. This study also demonstrates that,there exists a negative correlation between the serum H2S level and spot urinary protein level in preeclampsia patients.