Urinary Podocyte Excretion Research Articles

PS-C13-7: THE ROLE OF WATER HAMMER PRESSURE IN THE GLOMERULAR PODOCYTE SHEDDING AND RENAL PROGNOSIS

Objective: Urinary podocyte excretion is related to a reduction in glomerular podocyte numbers, glomerulosclerosis, and urinary protein selectivity. To elucidate the factors of urinary podocyte shedding and renal prognosis, we examined urinary podocytes in 120 renal biopsy patients. Design and method: Podocytes were identified in urinary sediments stained with fluorescent-labelled anti-podocalyxin antibodies in ten high power fields. The amounts of protein bands, separated by SDS-polyacrylamide gel electrophoresis, were calculated using an image software program. The renal prognosis, including induction of hemodialysis or 30% reduction in eGFR, was investigated. Results: Urinary podocyte excretion showed a higher positive correlation with albumin excretion compared to IgG, prealbumin, and transferrin, but not with low molecular weight proteins, including beta2-microglobulin and alpha1-microglobulin. The hemodynamic pressure on the glomerular capillary wall, including products of pulse pressure and pulse rate (water hammer pressure), was positively correlated with urinary podocyte excretion. Urinary podocyte excretion and Tamm-Horsfall protein were independent risk factors for renal prognosis. Conclusions: Urinary podocytes shed from glomerular capillaries by water hammer and were involved in albuminuria and renal prognosis of renal biopsy patients.

Urinary Podocyte Excretion Predicts Urinary Protein Selectivity and Renal Prognosis.

Background Urinary podocyte excretion is related to a reduction in glomerular podocyte numbers, glomerulosclerosis, and urinary protein selectivity. To elucidate the role of urinary podocytes in proteinuria and renal prognosis and to identify the factors that cause podocyte detachment, we examined urinary podocytes in 120 renal biopsy patients. Methods Podocytes were identified in urinary sediments stained with fluorescent-labeled anti-podocalyxin antibodies in ten high power fields. The amounts of protein bands, separated by SDS-polyacrylamide gel electrophoresis, were calculated using an image software program and the correlation with urinary podocytes was analyzed. Podocyte surface pores were observed using a low-vacuum scanning electron microscope. The renal prognosis, including induction of hemodialysis or 30% reduction in eGFR, was investigated. Results Urinary podocyte excretion showed a higher positive correlation with albumin excretion compared to IgG, prealbumin, and transferrin. There were no significant correlations between urinary podocyte count and low molecular weight proteins, including β2-microglobulin and α1-microglobulin. The number of podocyte surface pores was positively correlated with proteinuria, suggesting enhanced albumin transcytosis. The hemodynamic pressure on the glomerular capillary wall, including products of pulse pressure and pulse rate (water hammer pressure), was positively correlated with urinary podocyte excretion. Urinary podocyte excretion and Tamm–Horsfall protein (THP) were independent risk factors for renal prognosis but were not related to response to treatment. Conclusion Urinary podocyte excretion was correlated with urinary albumin excretion, indicating specific albumin transport by podocytes. Podocytes were detached from the glomerular capillaries by water hammer pressure and THP was involved in the renal prognosis.

MON-003 Relationship between urinary podocytes and urinary protein fraction evaluated by SDS-PAGE

Urinary podocyte excretion is associated with a reduction in glomerular podocyte number, glomerular sclerosis and urine protein selectivity.In the patients undergoing renal biopsy we examined the relationship between urinary podocytes and urinary protein fraction separated by SDS-polyacrylamide gel electrophoresis (PAGE). Urine sediment was stained with fluorescently labeled podocalyxin antibody and cells superimposed with phase contrast microscopic images were counted. The amount of protein bands separated by SDS-PAGE was calculated by NIH Image-J software and correlation with urine podocytes was examined. Urinary podocyte numbers were significantly correlated with amount of Tamm-Horsfall Protein (MW95kD, R=0.74, p<0.001), albumin (MW67kD, R=0.66, p<0.001), prealbumin (MW55kD, R=0.55, p<0.005) and transferrin (MW80kD, R=0.41, p<0.05). However, there were no significant correlation between urinary podocyte number and β２-microglobulin（MW12kD, R=0.14, p=0.49）, light chain (MW23kD, R=0.14, p=0.47), α１-microglobulin (33kD,R=0.056, p=0.78), IgG(MW160kD, R=0.09, p=0.64), IgG/Tf (R=0.11, p=0.57), or IgG/Alb (R=0.14, p=0.48). Urinary podocyte often contained lipid droplets in the vesicles. In conclusion, urinary podocyte excretion was correlated with urinary albumin and transferrin filtration and tubular excretion of THP.

236. Pregnancy in renal transplant patients: renal function markers and maternal-fetal outcomes

Progressive proteinuria and glomerulosclerosis characterize chronic allograft nephropathy. Podocytes are fundamental cells for maintaining the functionality of glomerular filtration barrier. Failure to achieve this task due to reduced podocyte number and results in progressive glomerular dysfunction, causing proteinuria and glomerulosclerosis and ultimately leading to end-stage kidney disease. Assessment of podocyturia and its correlation with other renal parameters could help with the diagnosis and definition of prognosis of the glomerulopathies, thus contributing to risk reduction. To evaluate podocyturia and others renal parameters as functional markers in pregnant women with kidney grafts. In this cross-sectional and prospective study, 43 pregnant women with kidney grafts had their Mid-stream urine samples collected to determine proteinuria, including retinol-binding protein (enzyme immunoassay using monoclonalantibodies), albumin/creatinine ratio (immunoturbidimetry), protein/creatinine ratio (the alkaline picrate colorimetric method), and podocyturia (indirect immunofluorescence). 43 women who got pregnant after renal transplantation were included. Podocyturia was not significantly correlated with other renal function markers. A gradual increase was observed in the following parameters during pregnancy and puerperium: serum creatinine levels (P < 0.001), proteinuria (P < 0.001), urinary protein/creatinine ratio (P < 0.001), and albumin/creatinine ratio (P < 0.001). Elevated serum creatinine levels, urinary albumin/creatinine ratio, and retinol-binding protein levels in the third trimester were associated with prematurity (P < 0.001). Preeclampsia was the main cause of renal function decline at the end of pregnancy (65.0% of cases). Proteinuria, urinary protein/creatinine ratio, and retinol-binding protein levels were elevated in patients with preeclampsia. Proteinuria (or more specifically, urinary protein/creatinine ratio) and albumin/creatinine ratio has also used as a marker of CKD progression. We observed that urinary podocyte excretion occurs in pregnant women with kidney transplant. Using these markers to assess renal function during pregnancy may be clinically useful for early diagnosis and follow-up of glomerular injury, eventually preeclampsia. It may be also associated to its severity or activity.

Application of Liquid Chromatography with Fluorimetric Detection for the Determination of Urinary Pentosidine in Type 2 Diabetes Mellitus Patients: Effect of Telmisartan Administration on Podocyturia and Relationship with Metabolic Control

The beneficial effects of a short period of Telmisartan administration were successfully assessed trough pentosidine urinary levels (uPen) and urinary podocyte excretion (UPE), in type 2 diabetes mellitus (DM2) patients. Patients with podocyturia received Telmisartan treatment (80 mg/day) for two months. uPen were quantified pre and post treatment using HPLC with fluorimetric detection and in-lab synthesized standard. Immunofluorescence method for podocalyxin was used to evaluate urinary excretion of podocytes. uPen and UPE significantly decrease after treatment (p&amp;lt;0.01255 and p&amp;lt;0.005 respectively), as well as serum total cholesterol and LDL levels (p&amp;lt;0.001). These results suggest that podocyte protection by Telmisartan even in the face of deficient metabolic control could be an important matter in the prevention and progression of diabetic nephropathy. This study also strengthens evidence of the promising role of pentosidine as prognostic and diagnostic markers in diabetic nephropathy

Cystinosin deficiency causes podocyte damage and loss associated with increased cell motility

The involvement of the glomerulus in the pathogenesis of cystinosis, caused by loss-of-function mutations in cystinosin (CTNS, 17p13), is a matter of controversy. Although patients with cystinosis demonstrate glomerular lesions and high-molecular-weight proteinuria starting from an early age, a mouse model of cystinosis develops only signs of proximal tubular dysfunction. Here we studied podocyte damage in patients with cystinosis by analyzing urinary podocyte excretion and by in vitro studies of podocytes deficient in cystinosin. Urine from patients with cystinosis presented a significantly higher amount of podocytes compared with controls. In culture, cystinotic podocytes accumulated cystine compatible with cystinosin deficiency. The expression of podocyte specific genes CD2AP, podocalyxin, and synaptopodin and of the WT1 protein was evident in all cell lines. Conditionally immortalized podocyte lines of 2 patients with different CTNS mutations had altered cytoskeleton, impaired cell adhesion sites, and increased individual cell motility. Moreover, these cells showed enhanced phosphorylation of both Akt1 and Akt2 (isoforms of protein kinase B). Inhibition of Akt by a specific inhibitor (Akti inhibitor 1/2) resulted in normalization of the hypermotile phenotype. Thus, our study extends the list of genetic disorders causing podocyte damage and provides the evidence of altered cell signaling cascades resulting in impaired cell adhesion and enhanced cell motility in cystinosis.

Is there a role for urinary podocyte excretion assessment in lupus nephritis?

Objective To establish the occurrence and intensity of podocyturia and its relation to grade of disease activity, as defined by clinical and laboratory criteria. Methods Prospective, cross-sectional study involving 50 patients with lupus nephritis and 29 controls, which had podocyturia levels determined from random urine samples using an immunofluorescence technique. Disease activity was graded by BILAG (renal criteria) and an additional system used in the service (S2). Results Fifty patients with lupus nephritis (WHO classes III, IV and V), with a median age of 37 years, were evaluated. Of these, 86.5% were female, and 52% were BILAG A. Podocyturia quantification in the lupus nephritis and control groups differed significantly (p = 0.009). This score was higher in relation to classes III, IV and V. The correlation with C3 consumption was stronger (p = 0.011) than with C4. The highest levels were found in the most active groups (A and B of BILAG and S2). Lower podocyturia correlated with a lower dose of prednisone. There was no association with the intensity of proteinuria, hematuria or pyuria, serum creatinine levels, among others. Conclusions Podocyturia assessment, which was performed by immunofluorescence in this study, can be used as an indicator of disease activity with the advantage of being a urinary biomarker. The levels proved to be higher in patients with lupus nephritis than in the controls and were particularly higher in class IV.

Podocyturia in Fabry disease.

Fabry disease is a lysosomal storage disorder due to abnormalities in the GLA gene (Xq22). Such changes result in the reduction/absence of activity of the lysosome enzyme α-GAL, whose function is to metabolize globotriaosylceramide (Gb3). Renal disease is a major clinical outcome of the accumulation of Gb3. Podocyte injury is thought to be a major contributor to the progressive loss of the renal function and may be found altered even before the onset of microalbuminuria. The aim of this study was to quantify the urinary excretion of podocytes in Fabry disease patients (V269M, n = 14) and healthy controls (n = 40), and to correlate podocyturia with the variables gender, age, time of therapy and albumin: creatinine ratio (ACR). Urinary podocytes were stained using immunofluorescence to podocalyxin and DAPi. The number of podocalyxin-positive cells was quantified and the average number was taken (normal range 0-0.6 podocytes/mL). The average number of podocytes in the urine of Fabry disease patients was significantly higher than in healthy controls (p < 0.0001). We observed a positive correlation between podocyturia and ACR (p = 0.004; (r2 = 0.6417). We found no correlation between podocyturia and gender, age or duration of therapy. Podocyturia is an important parameter in the assessment of renal disease in general, and it may serve as an additional early tool for monitoring Fabry disease nephropathy even before changes in ACR are seen. This may prove to be a useful tool to assess disease progression in patients expected to have a more aggressive phenotype.

Combination of Tripterygium wilfordii Hook F and angiotensin receptor blocker synergistically reduces excretion of urinary podocytes in patients with type 2 diabetic kidney disease

The aim of this study was to investigate whether Tripterygium wilfordii Hook F (TwHF) and irbesartan could synergistically affect the urinary excretion of podocytes and proteins in type 2 diabetic kidney disease (DKD) patients and the underlying mechanisms. Forty DKD patients were divided into a DI group (DKD patients treated with irbesartan alone) and a DTI group (DKD patients treated with Tripterygium wilfordii Hook F and irbesartan). Urinary podocytes were observed by immunofluorescence. Urinary levels of connective tissue growth factor (CTGF) and transforming growth factor-β1 (TGF-β1) were detected by enzyme-linked immunosorbent assay. Immunofluorescence indicated that shed podocytes were not detected in urine samples of normal controls, whereas the detection rate of urinary podocytes was 82.5% in DKD patients. Urinary CTGF and TGF-β1 levels were significantly higher in urinary podocyte-positive DKD patients than in urinary podocyte-negative patients. Furthermore, urinary podocyte excretion was closely correlated with urinary protein excretion and urinary CTGF/TGF-β1 levels. Treatments with TwHF and irbesartan significantly reduced the urinary excretion of proteins and podocytes, and decreased the urinary levels of CTGF and TGF-β1. Our results suggest that urinary podocyte excretion might serve as a predictor for DKD progression. TwHF/irbesartan combination could reduce the urinary excretion of proteins and podocytes synergistically in DKD patients, which might result from the synergistic inhibition of CTGF and TGF-β1 in urine.

Urinary Podocyte Excretion and Proteinuria in Patients Treated with Antivascular Endothelial Growth Factor Therapy for Solid Tumor Malignancies

Background: Urinary podocyte excretion (podocyturia) may function as a more specific marker of ongoing glomerular damage. This study sought to analyze the relationship between proteinuria and podocyturia in cancer patients treated with antivascular endothelial growth factor (anti-VEGF) agents. Methods: Thirty-seven patients treated with anti-VEGF medications were analyzed in a single-institution, cross-sectional study. Podocyte cultures were performed on random urine collections (50-100 ml), and podocytes were identified by positive podocin staining. The corresponding urine samples were analyzed for protein and creatinine (Cr) measurements. Results: Proteinuria ≥0.5 g/g Cr was found in 30% of the patients (median, 0.12; interquartile range, 0.04-0.86), and 62% had podocyturia. There was a significant difference in the amount of podocyturia between patients with proteinuria ≥0.5 g/g Cr and those with a value <0.5 g/g Cr (median podocyturia, 1.08 cells/mg Cr, range, 0-14.55 vs. 0.03 cells/mg Cr, range, 0-1.64, respectively; p < 0.001). A statistically significant correlation was observed between the cumulative dose of bevacizumab and both proteinuria (r = 0.48, p = 0.004) and podocyturia (r = 0.34, p = 0.045) as well as between proteinuria and podocyturia (r = 0.63, p < 0.001), suggesting that these are mechanistically related. Discussion: Ongoing podocyte loss may be mechanistically related to the onset and severity of proteinuria in patients treated with anti-VEGF agents.

Urinary and glomerular podocytes in patients with chronic kidney diseases

Podocytes are highly differentiated epithelial cells involved in glomerular filtration. This study determines the clinical and histological significance of podocyte detachment and excretion in urine in patients with chronic kidney diseases. Renal biopsy was performed in 59 patients (30 males, 29 females; mean age 48 ± 2 years), including 24 patients with immunoglobulin (Ig)A nephropathy, six each with focal segmental glomerulosclerosis, membranous nephropathy, and minimal change nephrotic syndrome, and 17 with other renal disorders. The number of glomerular podocytes and severity of morphological damage were evaluated in renal biopsy samples. Urinary podocytes were detected by anti-human podocalyxin antibody. The urinary IgG/albumin ratio and urinary peroxide products were assessed by gel electrophoresis and the 2',7'-dichlorodihydrofluorescein-diacetate method, respectively. A decrease in glomerular podocytes was associated with age (r = -0.33; P < 0.05), glomerulosclerosis (r = -0.43; P < 0.01), tubulointerstitial lesions (r = -0.46; P < 0.01), and low estimated glomerular filtration rates (r = 0.32; P < 0.05). Increased urinary podocyte excretion correlated with proteinuria (r = 0.36; P < 0.01), and was observed more frequently in patients with active histological lesions. Podocyte loss correlated with lower selectivity of proteinuria in patients with minimal change nephrotic syndrome and focal segmental glomerulosclerosis (r = -0.90; P < 0.001). Moreover, urinary peroxide products increased in association with glomerulosclerosis (r = 0.39; P < 0.05). Urinary podocyte excretion reflects ongoing glomerular injury in various kidney diseases, and podocyte loss correlated with glomerulosclerosis and impaired selectivity of proteinuria.

Effects of Angiogenic Factors, Antagonists, and Podocyte Injury on Development of Proteinuria in Preeclampsia

Proteinuria is universal to all patients with preeclampsia. We examined the urinary podocytes in women with preeclampsia (n = 14), gestational hypertension (n = 14), and normal pregnancy. Maternal serum and urinary concentrations of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), and the antiangiogenic factor soluble fms-like tyrosine kinase 1 (sFlt-1) were detected. These concentrations were used to evaluate the urinary excretion of podocytes and the alteration of angiogenic factors and to assess their relationships to proteinuria in preeclampsia. Our studies suggest that the urinary podocyte number and angiogenic factors are correlated with random urine albumin/creatinine ratio and blood pressure. Receiver-operating characteristic (ROC) curves of serum and urinary PlGF and the PlGF/sFlt-1 ratio as well as the presence of podocyturia confirmed their usefulness in distinguishing preeclamptic and normotensive pregnant women. In addition, combinations of serum or urinary PlGF or podocyturia tests in parallel or in series provided the best clue for identifying patients with preeclampsia. We considered that the dysregulation of angiogenic factors and its subsequent podocyte injury may contribute to the mechanism of proteinuria development in preeclampsia.

Atorvastatin ameliorates podocyte injury in patients with type 2 diabetes complicated with dyslipidemia

We examined the effects of atorvastatin on urinary podocyte excretion. Thirteen patients with type 2 diabetes receiving 2.5mg of rosuvastatin were recruited and the medication was switched to 10mg of atorvastatin for a 24-week period. With the switch to atorvastatin, the urinary excretion of podocytes was significantly reduced.

PP019 The role of renal markers in women with and without preeclampsia: Evaluation of urinary excretion of podocytes and proteins

Preeclampsia (PE) is an important cause of glomerulopathy. Assessment of renal markers during pregnancy may have a predictive value for glomerular disease later in life. The early detection of PE may prevent the complications of this syndrome. Assess the glomerular involvement in PE and in normal pregnancy by evaluating renal markers such as podocyturia and proteinuria. Case-control study with 39 pregnant women after 20 weeks of gestation (control group - CG with n=25 and PE with n=14), we assessed podocyturia (cytospin method) and proteinuria (albuminuria, urine protein:creatinine - PCR, urinary retinol protein - RBP and albumin/creatinine ratio - ACR). (Grant FAPESP 08/56338-1) RESULTS: Mean±standard deviation of age and mean gestational age of CG were 26.9±6.4years and 37.1±5.0weeks and of PE, 26.4±6.9 and 30.6±5.6, respectively (p=0.001). No statistical differences were found between podocyturia in CG and PE although it was more frequent in this last group (p=0.258). Podocyte cells and parietal epithelial cells were detected in the slides. Mean±standard deviation of urinary RBP (p=0.017), albuminuria (p=0.002) and UAC ratio (p=0.006) of CG were 0.4±0.7mg/L, 7.3±6.9mg/L and 8.2±6.7mg/g and of PE, 2.0±4.4mg/L, 2267.4±2130.8mg/L (p=0.002) and 3778.9±4296.6mg/g (p=0.006), respectively. Mean value±standard deviation of urine PCR in PE was 6.7±6.1g/g (p=< 0.001). Urinary RBP, PCR, albuminuria and UAC ratio were elevated in PE in comparison to CG indicating its glomerular involvement but there was no correlation between those renal parameters and podocyturia. RPC and UAC ratios were good predictors of PE, but not podocyturia. Either podocyte cells as parietal epithelial cells were detected in the urine, these findings may indicate a non-invasive marker for renal disease activity but more studies are required to determine its role in PE.

PP090. The contribution of podocyturia to the evaluation of ongoing glomerular disorder in pregnant women with kidney graft (preliminary results)

IntroductionProgressive proteinuria and glomerulosclerosis characterize chronic allograft nephropathy. However, the causes are not fully elucidated. Injury of parietal epithelial cells in glomeruli, the podocytes, is the initiating cause of many renal diseases, leading to proteinuria with possible progression to glomerulosclerosis. Podocytes are highly specialized cells, with an important role in maintaining the glomerular filtration barrier and producing growth factor for mesangial cells and endothelial cells. With their foot processes they cover the glomerular basement membrane, and form slit diaphragms with neighboring podocytes. The potential role of podocytes in the failing transplanted kidney is unknown. ObjectivesTo evaluate podocyturia as a functional marker in pregnant women with kidney grafts. MethodsTwenty pregnant women with kidney grafts had their urine samples cytocentrifugated and evaluated by indirect immunofluorescence. The slide was incubated for 45’ at room temperature with fluorescein (FITC) anti-rabbit IgG secondary antibody (Sigma-Aldrich, EUA). Then Vectashield (mounting medium for fluorescence) with DAPI (4’6-diamino-2-fenilindol dihidrocloreto) were applied H-1200 (Vector laboratories, inc, USA). The podocytes and the total number of cells were counted in 15 fields photographed under 400x magnification with a digital camera coupled to an epifluorescence microscope DM1000 (Leica, Germany) connected to a computer. The results were expressed as podocyte/total cells (%) per area of higher cell concentration (hot spots) in the field of 400x detected by staining of nuclei and cytoplasm. (Grant FAPESP 08/56338-1). ResultsThe mean age of the women was 26years. The urinalysis was performed at the third trimester of gestation; 11 did not exhibit urinary podocytes and 9 had podocyturia. There was also a relationship between blood pressure levels, proteinuria and the excretion of podocytes. ConclusionUrinary podocyte number, blood pressure and proteinuria were associated. We observed that urinary podocyte excretion occurs in pregnant women with kidney transplant almost synchronously with higher systolic and diastolic blood pressure and higher mean levels of proteinuria. The detection of podocyturia in these women could be useful for early diagnosis and follow-up of glomerular injury, eventually preeclampsia. It may be also associated to its severity or activity, although additional studies are necessary to confirm these aspects.

Evaluation of Renal Clinicopathological Changes in IgA Nephropathy by Urinary Podocytes Excretion and Podocalyxin Expression

Objective: To explore the association of urinary podocyte excretion and renal expression of podocyte-specific marker podocalyxin (PCX) with clinicopathological changes in immunoglobulin A nephropathy (IgAN). Methods: Morning urine samples from IgAN patients and healthy controls were collected. The expression of glomerular PCX was quantified in 50 IgAN patients diagnosed by renal biopsy. IgAN was classified based on the Lee’s Grading system and scored according to the Katafuchi semiquantitative criteria. Morphological evaluation of podocyte was determined by electron microscopy. Results: The amount of urinary podocytes in the IgAN patients was significantly higher than that in the healthy controls (p < 0.01). Pairwise comparison among Lee’s grades of IgAN showed that the median of urinary podocytes in Lee’s I–II group was lower than that in Lee’s III, IV, and V groups (p < 0.05); group III lower than group V (p < 0.05). The positive rate of urinary podocytes was the highest in Lee’s IV and V groups (100%), and lowest in Lee’s I–II group (55%). Multiple comparison among groups of Lee’s grades of IgAN showed that the glomerular PCX expression in Lee’s I–II group was higher than that in Lee’s III, IV, and V groups (p < 0.05); groups III and IV higher than group V (p < 0.05). The amount of urinary podocytes in IgAN patients was negatively correlated with PCX expression (r = −0.702, p < 0.01), but positively correlated with 24-h urinary protein (r = 0.465, p < 0.01) and glomerular (r = 0.233, p < 0.01) and renal tubular pathological scores (r = 0.307, p < 0.05). The glomerular PCX expression was negatively correlated with 24-h urinary protein (r = −0.367, p < 0.05) and glomerular (r = −0.560, p < 0.05) and tubular pathological scores (r = −0.377, p < 0.05). Electron microscopy showed significant changes in podocytes of IgAN, especially in the foot process. Conclusion: The amount of urinary podocyte can reflect the loss of podocytes in renal tissue, which may be a marker of IgAN progression.

Podocyte Detachment in Type 2 Diabetic Nephropathy

Background: Glomerular podocyte number declines and urinary excretion of podocytes increases as kidney disease progresses in persons with type 2 diabetes mellitus (T2DM). Methods: Using high-power electron microscopy, we quantified podocyte detachment in T2DM. Results: We evaluated 106 glomeruli (range 1–6 per subject) from 40 Pima Indian subjects with T2DM enrolled in a clinical trial. On high-power electron micrographs, 35% of the subjects had no evidence of podocyte detachment. Among the remaining subjects, the median percentage of basement membrane with podocyte detachment was 0.62% (interquartile range = 0.32–1.52%). Conclusion: Podocyte detachment from the glomerular basement membrane has been described and measured in type 1 diabetes mellitus using a different method. We now document podocyte detachment microscopically and quantify it morphometrically in humans with T2DM. The findings offer quantitative histologic support to a potential mechanism for the functional impairment, and possibly the sclerosis of glomeruli, in diabetic glomerular injury.

P47 Importance of renal function evaluation during pregnancy performed by obstetricians/gynecologists and residents

and 0.4g/24h for PE and 2.9mg/dl and 4.8g/24h for PG. Podocyte cells were observed in all three groups, but there were only significant numbers in PG and PE. In PE group it was found almost three times the quantity detected in PG. Conclusions: Urinary podocyte excretion occurs in PE and PG besides other renal abnormalities; furthermore, it may contribute to the development of glomerulosclerosis. The detection of podocyturia in PE could be useful for preventing, diagnosing and following up the glomerular injury and it may also be correlated to its severity or activity, although additional studies are necessary to confirm these points. Apoio FAPESP 08/56338-1

Spironolactone ameliorates podocytic adhesive capacity via restoring integrin α3 expression in streptozotocin-induced diabetic rats

Podocyte responses to various injuries include detachment from the glomerular basement membrane (GBM) with impaired adhesion ability. Growing evidence suggests inappropriately enhanced aldosterone levels in glomeruli may contribute to podocytic injury and subsequently glomerulosclerosis in diabetic nephropathy (DN). In the present study, we aimed to investigate podocytic integrin alpha 3 expression and urinary podocyte excretion in streptozotocin (STZ)-induced diabetic rats, and to evaluate their responses to spironolactone (SPL). STZ-induced male diabetic Wistar rats were treated with vehicle (the STZ group, n=7), or spironolactone (the STZ+SPL group, n=6) for 12 weeks, six additional rats of similar body weight serving as control. Urine specimens were obtained for measurement of urine albumin concentration and urinary podocyte quantitation upon completion of the 12 weeks. Urinary podocyte excretion was quantified by immunofluorescence and expression of integrin alpha 3 was detected by immunohistochemistry and Western blotting. At 12 weeks, rats given STZ alone revealed an increase in blood glucose and were unaffected by spironolactone, whereas the STZ+SPL group showed considerable improvement in urine albumin and podocyte excretion, as well as up-regulation of integrin alpha 3. Our results suggest that spironolactone ameliorates impaired podocytic adhesion capacity and prevents STZ-induced DN progression.

281: Urinary Excretion of Podocytes as an Early Marker of Diabetic Nephropathy

281: Urinary Excretion of Podocytes as an Early Marker of Diabetic Nephropathy