Urinary Nephrin Research Articles

Urinary nephrin as a marker of nephropathy in obese prediabetic patients

Background: One of the most important complications of obesity and prediabetes is nephropathy. In the Eastern Mediterranean area, the incidence of obesity is always growing. In Saudi Arabia, Egypt, Kuwait, the United Arab Emirates, and Bahrain, the highest level of obesity is found in 15-year-old adults and also in older adults. Obesity and overweight are prevalent in the preceding countries at rates ranging from 69% to 77% in men and 74% to 80% in women, making it critical to distinguish nephropathy in these patients for a better prognosis. Objective: To assess the level of urine nephrin as a nephropathy marker in obese and prediabetic patients. Patients and Methods: This was cross-sectional observational research that included 90 people. Their ages varied from 30 to 70 years old, and they came from Dar El-Shefa hospital's outpatient clinic between December 2019 and May 2020. The study was explained to all participants, and their informed consent was acquired before the start of the trial. The subjects were split into three groups: group I (thirty normoalbuminuric obese non-diabetic patients), group II (thirty normoalbuminuric obese pre-diabetic patients), and group III (thirty healthy control).

Nephrinuria and podocytopathies.

The discovery of nephrin in 1998 has launched a new era in glomerular diseases research, emphasizing its crucial role in the structure and function of the glomerular filtration barrier. In the past 20 years, substantial advances have been made in understanding podocyte structure and function as well as the discovery of several podocyte-related proteins including nephrin. The glomerular filtration barrier is comprised of podocytes, the glomerular basement membrane and endothelial cells. Podocytes, with their specialized slit diaphragm, form the essential backbone of the glomerular filtration barrier. Nephrin is a crucial structural and functional feature of the slit diaphragm that prevents plasma protein, blood cell and macromolecule leakage into the urine. Podocyte damage results in nephrin release. Podocytopathies are kidney diseases in which podocyte damage drives proteinuria, i.e., nephrotic syndrome. Many kidney diseases involve podocytopathy including congenital nephrotic syndrome of Finnish type, diffuse mesangial sclerosis, minimal change disease, focal segmental glomerulosclerosis, collapsing glomerulonephropathy, diabetic nephropathy, lupus nephropathy, hypertensive nephropathy and preeclampsia. Recently, urinary nephrin measurement has become important in the early detection of podocytopathies. In this chapter, we elaborate the main structural and functional features of nephrin as a podocyte-specific protein, pathomechanisms of podocytopathies which result in nephrinuria, highlight the most commonly used methods for detecting urinary nephrin and investigate the diagnostic, prognostic and potential therapeutic relevance of urinary nephrin in primary and secondary proteinuric kidney diseases.

Effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on podocytes, inflammation, and oxidative stress in patients with diabetic nephropathy (DN).

Objectives:To investigate the effects of a glucagon-like peptide-1 receptor agonist (GLP-1RA) liraglutide on podocytes, inflammation, and oxidative stress in patients with diabetic nephropathy (DN).Methods:Eighty-four DN patients treated by the department of endocrinology of the Affiliated Hospital of Hebei University during December 2017 and March 2019 were randomly assigned to a control group and a treatment group (n=42, respectively), with the control group prescribed with conventional DN medications and the treatment group receiving liraglutide treatment in addition to the conventional therapy. The course of treatment lasted for 12 weeks. hemoglobin A1c (HbA1C), body mass index (BMI), total cholesterol (TC), triglyceride (TG), urinary albumin excretion rate (UAER), urine podocalyxin (PCX), urine nephrin, as well as inflammation and oxidative stress markers such as tumor necrosis factor α (TNF-α), monocyte chemotactic protein-1 (MCP-1), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were measured pre- and post-treatment for intergroup comparison.Results:After 12 weeks of treatment, HbA1C, BMI, TC, and TG in both groups were reduced in comparison with the pre-treatment levels, with the levels in the treatment group lower than in the control group (p<0.05); reduced levels of UAER, PCX, and nephrin were detected in the two groups, with the treatment group exhibiting a significant reduction in these markers compared with the control group (p<0.05); the 12-week treatment led to decreases in the TNF-α, MCP-1, and MDA levels in both groups, with the decline in the treatment group exceeding that in the control group, whereas both groups had an increased level of GSH-Px, with the level in the treatment group higher than that in the control group, and the differences were statistically significant (p<0.05, respectively).Conclusions:Liraglutide protects the kidneys and improves DN by inhibiting inflammation and oxidative stress, reducing urinary albumin excretion and podocyte damage and supporting renal function in addition to its hypoglycemic properties.

Urinary Nephrin as a Marker of Glomerular Diseases in Pediatric Patients.

Urinary Nephrin as a Marker of Glomerular Diseases in Pediatric Patients.

Urinary Nephrin and Podocalyxin Levels as Predictors of Pre-eclampsia in High-Risk Pregnant Women.

Pre-eclampsia (PE) is characterized by new-onset hypertension and proteinuria. Damage of podocyte cells has been reported in pre-eclamptic women, thus podocyte specific proteins such as nephrin and podocalyxin could be useful biomarkers in PE. To investigate the role of urinary nephrin (u-nephrin) and urinary podocalyxin (u-PDX) levels in predicting PE in women with a high-risk pregnancy. We included 101 pregnant women in this study and allocated them into three groups: group 1 included pregnant women at high risk of developing PE (n=41), group 2 - pregnant women with PE (n=30), and group 3 was the controls including healthy pregnant women (n=30). The inclusion criteria for women with PE were de novo hypertension >140/90 mm Hg, proteinuria >300 mg/24 hours, and presence of edema after 20 weeks of gestation, while the exclusion criteria were a history of renal diseases and pregnant women younger than 18. Inclusion criteria for the group of women with a high-risk pregnancy was gestational week >15, a history of PE in a previous pregnancy, pre-existing diabetes type 1 or 2, pre-existing hypertension, multiple gestations, prior placental abruption, obesity women, nulliparity, maternal age >35 years, and a family history of PE. The study was conducted from March 2016 to May 2017 in the Medical Faculty at the Institute of Medical and Experimental Biochemistry in Skopje. Urine samples were used to measure the nephrin and podocalyxin levels using immunoenzyme assay, creatinine and microalbumin. Blood samples were collected for biochemical analyses. U-nephrin levels were elevated in 96.7% of women with PE, and 73% of women with a high-risk pregnancy. U-PDX levels were elevated in 63% of the women with PE and 100% of the women with a high-risk pregnancy. U-nephrin and u-PDX levels were significantly increased in women with a high-risk pregnancy and women with PE compared with a control group (p.

Nephrin in maternal urine as a simple biomarker to predict preeclampsia

Nephrin is a protein identified in the glomerular podocyte slit diaphragm; therefore, the presence of nephrin in urine implies damage to podocytes. Nephrin has been widely studied in nephropathies and glomerular diseases in adults. This study aimed to determine the efficacy of nephrin as a biomarker in maternal urine for the prediction of preeclampsia.

Utility of Urinary Nephrin in Patients With and Without Diabetic Nephropathy and Its Correlation With Albuminuria.

IntroductionNephrin is a podocyte-specific protein that may serve as a urinary biomarker in patients with diabetic nephropathy. The objectives of the study were to determine urinary nephrin levels in patients with and without type 2 diabetic nephropathy and to assess the correlation between urinary nephrin and albuminuria.MethodsThis was a cross-sectional comparative study that was carried out at Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry over 18 months. Diabetic study subjects were divided into three groups-normoalbuminuria, microalbuminuria, and macroalbuminuria. Urinary albumin was detected by the dipstick method in a spot urine sample for all study subjects. In subjects with trace or no albuminuria, nephelometry was used to quantify urinary albumin levels. Urinary nephrin was estimated by the ELISA technique for all study subjects.ResultsSubjects in the microalbuminuria group had higher urinary nephrin levels than those in the normoalbuminuria and macroalbuminuria groups. There was a weak positive correlation between urinary albumin and nephrin levels among the study subjects (p < 0.001).ConclusionUrinary nephrin levels are increased in patients with diabetic nephropathy. There was a weak positive correlation between urinary albumin and nephrin levels among these patients.

Urinary Matrix Metalloproteinase-9 and Nephrin in Idiopathic Membranous Nephropathy: A Cross-Sectional Study.

Aim Idiopathic membranous nephropathy (IMN) has a varied clinical course that requires accurate prediction as a prerequisite for treatment administration. Currently, its prognosis relies on proteinuria, a clinical parameter whose onset lags behind kidney injury. Increased urinary excretion of matrix metalloproteinase-9 (MMP-9) and nephrin has been reported in a number of IMN-like glomerular diseases in which they reflected disease severity. However, little or nothing is known of the importance of these biomarkers in IMN, a major cause of adult nephrotic syndrome. To highlight their potential, we measured both biomarkers and assessed their relationships with key parameters of renal function in IMN. Methods We quantified urinary MMP-9 and nephrin in 107 biopsy-proven IMN patients and 70 healthy subjects by enzyme-linked immunosorbent assay (ELISA). We then compared biomarker levels between patients and healthy subjects and among patients with different clinical features. We also determined the relationship of each biomarker with proteinuria and the estimated glomerular filtration rate (eGFR). Results Urinary MMP-9 and nephrin were significantly higher in IMN compared to healthy controls. Unlike nephrin, MMP-9 correlated significantly with proteinuria and was significantly higher among patients with nephrotic range proteinuria. Both biomarkers were correlated with eGFR, but only MMP-9 was significantly higher in patients with eGFR less than 90 ml/min/1.73 m2. Conclusion Our findings suggest that urinary MMP-9 holds a greater potential than urinary nephrin in monitoring the severity of IMN.

Diagnostic role of urine specific gravity to detect kidney impairment on heat-exposed workers in a shoe factory in Indonesia: a cross-sectional study

ObjectivesGlobally, there are increasing cases of chronic kidney disease of unknown origin among heat-exposed workers. We aimed to see the kidney damages of indoor heat-exposed workers and whether urine specific...

Blocking angiotensin 2 receptor attenuates diabetic nephropathy via mitigating ANGPTL2/TL4/NF-κB expression.

Diabetic nephropathy (DN) is a consequence of diabetes mellitus (DM) and is associated with early changes in renal angiotensin II (ANG II). These changes were evaluated using ANG II blocker valsartan early from week two of diabetes (experiment I, renoprotective) and late from week nine of diabetes (experiment II, renotherapeutic) to the end of both experiments at week twelve. In both experiments, adult male Wister rats were divided into (i) vehicle group; (ii) valsartan received oral 30mg/Kg/day; (iii) diabetic received single 50mg/Kg intraperitoneal streptozotocin injection; (iv) renoprotection, diabetic rats received valsartan treated in experiments I and II. DM effects on urine albumin excretion, blood pressure, and renal ANG II were measured. Urinary nephrin, kidney injury molecule-1 (KIM-1), renal angiopoietin-like protein 2 (ANGPTL2), and toll-like receptor 4 (TLR 4) mRNA expression were tested. DM-initiated fibrotic markers integrin, α-smooth muscle actin expression, and collagen IV and apoptotic protein caspase 3 were tested. DM induced early changes starting from week four in the tested variables. At week twelve, in both experiments, valsartan intervention showed a significant reduction in ANG II, ANGPTL2, TLR 4 and integrin expression and improvement in albuminuria, blood pressure, urinary biomarkers, fibrotic and apoptotic markers. Changes leading to DN starts early in the disease course and ANG II reduction decreased the expression of ANGPTL2 and integrin which preserve the glomerular barrier. Blocking ANG II was able to decrease TLR 4 and inflammatory cytokines leading to decreasing DN.

Glomerular Damage in Trichloroethylene-Sensitized Mice: Targeting Cathepsin L-Induced Hyperactive mTOR Signaling.

Trichloroethylene (TCE) is a serious health hazard for workers with daily exposure, causing occupational medicamentosa-like dermatitis due to TCE (OMDT) and glomerular damage. Recent studies suggest that mTORC1 signaling is activated in various glomerular disorders; however, the role of mTORC1 signaling in TCE-induced glomerular damage remains to be explored. In the present study, 6 OMDT patients were enrolled and a TCE-sensitized mouse model was established to investigate molecular mechanisms underlying the glomerular damage associated with OMDT. Glomerular damage was assessed by levels of urine nephrin, H&E staining, and renal function test. Ultrastructural change of podocyte was investigated by transmission electron microscopy. The podocyte-related molecules including nephrin, α-actinin-4, and integrin β1 were visualized by immunofluorescence. The activation of mTORC1 signaling was confirmed by Western blot. Glomerular apoptosis was examined by the TUNEL test and Western blotting. Expression and location of cathepsin L (CTSL) were assessed by RT-PCR and immunofluorescence. Our results showed that TCE sensitization caused damage to glomerular structural integrity and also increased the activation of mTORC1 signaling, which was accompanied by podocyte loss, hypertrophy, and glomerular apoptosis. Importantly, we also found that over-expressed CTSL was mainly located in podocyte and CTSL inhibition could partially block the activation of mTORC1 signaling. Thus, our findings suggested a novel mechanism whereby hyperactive mTOR signaling contributes to TCE sensitization–induced and immune-mediated glomerular damage via CTSL activation.

MO365URINARY BIOMARKERS AND POOR OUTCOMES IN PATIENTS WITH COVID-19 ADMITTED TO A REFERENCE HOSPITAL IN NORTHEAST BRAZIL

Background and AimsKidney biomarkers improve early and specific AKI detection and also poor outcomes in different clinical contexts. Kidney disease is an important risk factor for poor outcomes in COVID-19. The aim of this study was to evaluate association of early levels of kidney biomarkers with poor outcomes in hospitalized patients with COVID-19.MethodThis is a prospective study conducted at the Instituto Dr. Jose Frota Hospital, an important public reference hospital for COVID-19 in northeast Brazil. Medical records with clinical, epidemiologic, laboratory and outcomes were collected. The urinary NGAL, KIM-1, MCP-1 and nephrin were the kidney biomarkers quantified at hospital admission. ELISA assays were used for analysis and biomarkers urinary concentrations were adjusted for urinary creatinine. Data were expressed as mean± standard deviation or median.ResultsA total of 69 patients collected urine and were included in this study. Male gender was predominant (65%) and mean age was 56±19 years. Regarding outcomes, the group had 62% of death, 92% of ICU admission and 65% of invasive respiratory support in ICU. Urinary NGAL and MCP-1 were significantly elevated in patients that needed invasive respiratory support in comparison with non-invasive support: uNGAL (median=104 [IQR=74-153] vs 71 [31-79] ng/mg-Cr, p=0.013), and uMCP-1 (3055 [1127-5008] vs 1315 [574-2127] pg/mg-Cr, p=0.027). Urinary nephrin and KIM-1 was also elevated, however with no statistical significance. Moreover, all urinary biomarkers were higher in ICU admission group and death group, but with p>0.05. In ROC curve analysis for prediction of invasive respiratory support, uNGAL had AUC=0.696 (0.565-0.827),p=0.012 and cut-off=78 ng/mg-Cr; uMCP-1 had AUC=0.676 (0.539-0.813), p=0.023 and cut-off=1354 pg/mg-Cr. In survival analysis, patients with uNGAL >78 ng/mg-Cr had worse prognosis and died more quickly (19 vs 48 days, log-rank test; p=0.01). In patients with uMCP-1 >1354 pg/mg-Cr, they also died more quickly, but with no significance (25 vs 48 days, log-rank test; p=0.08).ConclusionUrinary biomarkers NGAL and MCP-1 quantified at hospital admission were associated with poor outcomes, mostly with needed of invasive respiratory support in ICU. Prediction cut-off values for invasive respiratory support was useful to determine the survival prognosis.

β-LAPachone is renoprotective in streptozotocin-induced diabetic mice via regulating the PI3K/Akt/mTOR signaling pathway.

Objective(s):β-LAPachone (B-LAP) is a natural product with established anti-inflammatory properties. In this study, we investigated the protective potential of B-LAP against diabetic nephropathy in streptozotocin (STZ) induced diabetic mice.Materials and Methods: Diabetes induction in mice was carried out by a single intraperitoneal injection of STZ. 2.5 mg/kg/day and 5 mg/kg/day doses of B-LAP were administered orally for twelve weeks and renal histoarchitecture, caspase-3, tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), glutathione peroxidase (GPX), as well as urinary nephrin and neutrophil gelatinase-associated lipocalin (NGAL) were evaluated. Additionally, kidney levels of PI3K, phosphorylated (p)-Akt, p-mTOR, p-CREB, and SIRT1 were assessed in the present investigation.Results: 5 mg/kg B-LAP significantly decreased urinary excretions of nephrin and NGAL. It also mitigated renal TNF-α and MDA levels and simultaneously improved GPX activities. 5 mg/kg B-LAP improved renal function in diabetic mice as indicated by elevated values of creatinine clearance. While B-LAP elevated renal levels of SIRT1, it alleviated PI3K, p-Akt, p-mTOR, and p-CREB levels in the kidneys of diabetic mice.Conclusion:Collectively, these findings suggest B-LAP as a potential renoprotective agent in STZ-induced diabetic mice probably via modulating the PI3K/Akt/mTOR pathway.

Sexual dimorphism in the progression of type 2 diabetic kidney disease in T2DN rats.

Diabetic kidney disease (DKD) is a common complication of diabetes, which frequently leads to end-stage renal failure and increases cardiovascular disease risk. Hyperglycemia promotes renal pathologies such as glomerulosclerosis, tubular hypertrophy, microalbuminuria, and a decline in glomerular filtration rate. Importantly, recent clinical data have demonstrated distinct sexual dimorphism in the pathogenesis of DKD in people with diabetes, which impacts both severity- and age-related risk factors. This study aimed to define sexual dimorphism and renal function in a nonobese type 2 diabetes model with the spontaneous development of advanced diabetic nephropathy (T2DN rats). T2DN rats at 12- and over 48-wk old were used to define disease progression and kidney injury development. We found impaired glucose tolerance and glomerular hyperfiltration in T2DN rats to compare with nondiabetic Wistar control. The T2DN rat displays a significant sexual dimorphism in insulin resistance, plasma cholesterol, renal and glomerular injury, urinary nephrin shedding, and albumin handling. Our results indicate that both male and female T2DN rats developed nonobese type 2 DKD phenotype, where the females had significant protection from the development of severe forms of DKD. Our findings provide further evidence for the T2DN rat strain's effectiveness for studying the multiple facets of DKD.

A Study of Association of Urinary Nephrin with Albuminuria in Patients with Diabetic Nephropathy.

Background and Aims:Diabetes mellitus and its complications are associated with high mortality and morbidity. Early detection is mandatory to improve quality of life years in patients with diabetic nephropathy. Hyperglycaemia disrupts podocytes, both structurally and functionally, leading to excretion of nephrin which is present in the glomerular filtration barrier. This study was undertaken to find out whether urinary nephrin is a better indicator of podocyte injury than albuminuria in patients with diabetic nephropathy.Methods:The study included 125 type 2 diabetes mellitus patients as cases categorized into three groups, depending upon albumin excretion. Age and sex matched 45 individuals without diabetes mellitus were chosen as the control group. The study protocol was approved by Institutional Ethics committee. Microalbumin was estimated by immunoturbidometry and urinary nephrin by ELISA. ANOVA and Tukey post-hoc tests were done to compare the data between the groups. Correlation studies were done. Odds ratio for nephrin was calculated. P value less than 0.05 was considered statistically significant. The statistical analyses were performed with SPSS software version 13.0.Results:The urinary nephrin was found to be proportionately increased from normoalbuminuria to macroalbuminuria and it was statistically significant, with sensitivity of 92.5% and specificity of 76.7%, the cut-off value of urinary nephrin was 97.5ng/mL.Conclusion:Albuminuria has been used as an independent predictor of diabetic nephropathy. The statistical significant difference between the groups inferred that urinary nephrin excretion increased even in the stage of normoalbuminuria. Nephrin expression and its phosphorylation get altered by hyperglycaemia, contributing to renal damage. Nephrin was found to be a sensitive marker of early kidney dysfunction in diabetic patients.

Protective Effect of Angiotensin II Type 1-Receptor-Blocker on Diabetic Nephropathy in Rats: Role of Nephrin

Abstract Background: Angiotensin II-Receptor Blockers (ARBs) has a questionable nephroprotective effect especially in diabetic nephropathy. Nephrin protein molecules exist in the slit diaphragm of the glomerular filtration membrane and control the passage of plasma protein. Aim of Study: To examine the possible role of Nephrin in the pathogenesis of diabetic nephropathy and the protective effect of ATII-RB (candesartan) on diabetic nephropathy. Material and Methods: Thirty-two male rats were used in this experiment. Half of the rats were fed a high-fat diet (HFD) and the other half were fed a standard diet for 4 weeks. A model of diabetic nephropathy (DN) was created by a 35mg/kg intraperitoneal dose of Streptozotocin (STZ) in the HFD-fed rats. Then the rats were divided into four groups (8 rats/group). (1) Normal control (NC) group; (2) Diabetic nephropathy (DN) group; (3) ARB-treated NC group: Normal rats were treated with the ARB (Candesartan Cilexetil), in a dose 0.1mg/kg; (4) ARB-treated DN group: The rats with DN and received the above dose of candesartan for 4 weeks. The urine was collected to measure the urine flow rate, urinary concentrations of Nephrin, creatinine, and protein. Blood samples were used to measure urea, creatinine, glucose, insulin, and the homeostatic model assessment (HOMA-IR). Then renal tissue samples were used to measure Superoxide dismutase (SOD) activity and Malondialdehyde (MDA) in addition to histopathological examination. The mean arterial blood pressure (MABP) was also recorded. Results: Candesartan treatment in the DN group showed significant reductions of glucose, HOMA-IR, amelioration of renal antioxidant system, reductions in creatinine, reduction of proteinuria, reduction of urinary Nephrin, and MABP. Histological improvement was also detected in the form of mild glomerulosclerosis and interstitial fibrosis. The urinary Nephrin was 90 times high in the condition of DN. This huge rise of urinary Nephrin was significantly reduced by Cande-sartan treatment. Moreover, in the DN group the urinary Nephrin level showed a significant correlation with glucose level, serum creatinine, urinary protein-creatinine ratio, and MABP.Conclusion: ATII-RB could reduce urinary Nephrin ex-cretion and possibly alters its expression through its inhibitory effect on the reactive oxygen species, the Renin-Angiotensin-Aldosterone system and subsequently maintains the normal physiological activity of podocytes in rats with STZ-induced diabetic nephropathy.

Glomerular filtration barrier dysfunction in a self-limiting, RNA virus-induced glomerulopathy resembles findings in idiopathic nephrotic syndromes

Podocyte injury has recently been described as unifying feature in idiopathic nephrotic syndromes (INS). Puumala hantavirus (PUUV) infection represents a unique RNA virus-induced renal disease with significant proteinuria. The underlying pathomechanism is unclear. We hypothesized that PUUV infection results in podocyte injury, similar to findings in INS. We therefore analyzed standard markers of glomerular proteinuria (e.g. immunoglobulin G [IgG]), urinary nephrin excretion (podocyte injury) and serum levels of the soluble urokinase plasminogen activator receptor (suPAR), a proposed pathomechanically involved molecule in INS, in PUUV-infected patients. Hantavirus patients showed significantly increased urinary nephrin, IgG and serum suPAR concentrations compared to healthy controls. Nephrin and IgG levels were significantly higher in patients with severe proteinuria than with mild proteinuria, and nephrin correlated strongly with biomarkers of glomerular proteinuria over time. Congruently, electron microcopy analyses showed a focal podocyte foot process effacement. suPAR correlated significantly with urinary nephrin, IgG and albumin levels, suggesting suPAR as a pathophysiological mediator in podocyte dysfunction. In contrast to INS, proteinuria recovered autonomously in hantavirus patients. This study reveals podocyte injury as main cause of proteinuria in hantavirus patients. A better understanding of the regenerative nature of hantavirus-induced glomerulopathy may generate new therapeutic approaches for INS.

The utility of urinary biomarker panel in predicting renal pathology and treatment response in Chinese lupus nephritis patients.

Given the urgent need for non-invasive biomarkers of LN, we aim to identify novel urinary biomarkers that facilitate diagnosis, assessment of disease activity and prediction of treatment response in a retrospective SLE cohort. A total of 154 SLE patients and 55 healthy controls were enrolled, among whom 73 were active LN patients. We measured renal activity by renal SLEDAI. The treatment response of the active LN patients who finished 6-month induction therapy was assessed based on the American College of Rheumatology response criteria. The expression levels of 10 urinary biomarkers (UBMs): β2-MG, calbindin D, cystatin C, IL-18, KIM-1, MCP-1, nephrin, NGAL, VCAM-1, and VDBP were tested using Luminex high-throughput proteomics technology. All but urinary nephrin levels were significantly increased in active LN compared to healthy controls. uCystatinC, uMCP-1, uKIM-1 levels were significantly higher in active LN group compared to inactive LN group. Correlation analysis revealed positive correlation between uCystatinC, uKIM-1, uMCP-1, uNGAL, uVDBP and RSLEDAI score. In renal pathology, uCystatinC, uKIM-1, uVCAM-1, and uVDBP positively correlated with activity index (AI) while uVCAM-1 positively correlated with chronicity index (CI). Moreover, the combination of uVCAM-1, uCystatinC, uKIM-1 discriminated proliferative LN from membranous LN with an AUC of 0.80 (95%CI: 0.69-0.90). Most importantly, baseline uNGAL demonstrated good prediction ability to discriminate responders from non-responders in active LN patients after 6-month induction therapy. Using a multiplex bead technique, we have identified the combination of uVCAM-1, uCystatinC, uKIM-1 as a biomarker panel to reflect renal pathology and NGAL as a promising urinary biomarker to both reflect disease activity and predict treatment response.

Multiplex Bead Array Assay of a Panel of Circulating Cytokines and Growth Factors in Patients with Albuminuric and Non-AlbuminuricDiabetic Kidney Disease.

A panel of cytokines and growth factors, mediating low-grade inflammation and fibrosis, was assessed in patients with type 2 diabetes (T2D) and different patterns of chronic kidney disease (CKD). Patients with long-term T2D (N = 130) were classified into four groups: no signs of CKD; estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 without albuminuria; albuminuria and eGFR ≥60 mL/min/1.73 m2; albuminuria and eGFR <60 mL/min/1.73 m2. Thirty healthy subjects were acted as control. Twenty-seven cytokines and growth factors were assessed in serum by multiplex bead array assay. Serum hs-CRP, urinary nephrin, podocine, and WFDC2 were measured by ELISA. Patients with T2D showed elevated IL-1Ra, IL-6, IL-17A, G-CSF, IP-10, MIP-1α, and bFGF levels; concentrations of IL-4, IL-12, IL-15, INF-γ, and VEGF were decreased. IL-6, IL-17A, G-CSF, MIP-1α, and bFGF correlated negatively with eGFR; IL-10 and VEGF demonstrated negative associations with WFDC2; no relationships with podocyte markers were found. Adjusted IL-17A and MIP-1α were predictors of non-albuminuric CKD, IL-13 predicted albuminuria with preserved renal function, meanwhile, IL-6 and hsCRP were predictors of albuminuria with eGFR decline. Therefore, albuminuric and non-albuminuric CKD in T2D patients are associated with different pro-inflammatory shifts in the panel of circulating cytokines.

Abstract MP09: Sex Differences And Development Of Advanced Diabetic Nephropathy In Type 2 Diabetic Nephropathy Rats

Diabetic kidney disease (DKD) is a severe complication of diabetes, which causes an increased risk of cardiovascular diseases and end-stage renal failure. Recent clinical data have demonstrated distinct sexual dimorphisms in the pathogenesis of DKD in humans, which impacts both severity- and age-related risk factors. A type 2 diabetic nephropathy (T2DN) rat model characterized by spontaneous development of an advanced form of diabetic nephropathy (DN) was used here to study sexual dimorphisms in the development of type 2 diabetes with DN. Male and female T2DN rats at late stages of the disease were used to evaluate hyperglycemia, renal injury, and kidney function. During late stage DKD (&gt;46 weeks), glucose tolerance tests (GTT) revealed higher glucose levels in males (378 ± 19 vs. 183 ± 48 mg/dL) compared to females. This was accompanied by pathological changes in kidney function including urinary nephrin shedding, albuminuria (11.8 ± 5.7 vs. 0.98 ± 0.64 Alb/Cre ratio), and glomerular damage. To test the role of the endocrine environment in the pathophysiology of type 2 diabetes with DKD, we performed gonadectomies on male and female T2DN rats at 9 to 10 weeks of age, and animals were monitored until the full development of DKD (&gt;46 weeks). All T2DN rats (intact and gonadectomized) maintained their diabetic phenotype, which was verified by higher end point blood glucose levels following a GTT (intact vs gonadectomized, male and female, respectively; 404 ± 21 vs 466 ± 32 and 264 ± 20 vs 291 ± 25 mg/dL). Based on kidneys to body weight ratios, gonadectomized male T2DN rats had a significant reduction in kidney hypertrophy (intact vs gonadectomized; males and females, respectively: 9.9 ± 0.2 vs 7.4 ± 0.2 and 7.7 ± 0.2 vs 7.0 ± 0.2 ratio). Moreover, FITC-inulin based GFR measurements revealed gonadectomized males had improved GFRs, whereas the GFRs of gonadectomized females rats were worsened (7.5 ± 1.5 vs. 4.1 ± 0.7 for male and 4.1 ± 0.2 vs. 7.3 ± 1.3 for female μg/mL/min; gonadectomy vs intact, correspondingly). In conclusion, male T2DN rats develop more severe DKD compared to age-matched females, and this phenotype is partially attenuated by the absence of sex hormones in males and exacerbated by the absence of hormones in females.