Gnetin C, a resveratrol dimer, reduces amyloid-ß 1-42 (Aß42) production and ameliorates Aß42-lowered cell viability in cultured SH-SY5Y human neuroblastoma cells.

Accumulation and oligomerization of amyloid-beta (Aß) peptides have been known to be a potent cause of neurodegenerative diseases such as Alzheimer's disease (AD). To expand the possibilities of preventing AD, we investigated the effects of resveratrol dimers, gnetin C and ε-viniferin, on Aß 1-42 (Aß42) production and the reduced cell viability observed after Aß42 treatment (monomers, 10 µM) in cultured SH-SY5Y human neuroblastoma cells. Among them, addition of gnetin C (20 µM) into the media reduced Aß42 production most efficiently. Gnetin C suppressed the expression of ß-site amyloid precursor protein-cleaving enzyme-1 (BACE1, ß-secretase). Furthermore, gnetin C ameliorated the Aß42-reduced cell viability most significantly. Concomitantly, gnetin C reduced intracellular Aß oligomers (ca. 15 and 130 kDa) and elevated both levels of intracellular and extracellular Aß monomers. Under the treatment with or without Aß42, gnetin C upregulated the expression of matrix metalloproteinase-14 (MMP-14) which is assumed to be an Aß-decomposing enzyme. Gnetin C may thereby prevent Aß toxicity by suppressing BACE1 and enhancing MMP-14, together with reducing both internalization and oligomerization of exogenous Aß monomers. The use of gnetin C may lead to the prevention of Aß-mediated diseases, particularly AD.

Toll-Like Receptor 3 Signaling Contributes to Regional Neutrophil Recruitment in Cultured Human Glomerular Endothelial Cells.

BACKGROUND: Given the importance of neutrophil recruitment in the pathogenesis of glomerulonephritis (GN), the representative neutrophil chemoattractant C-X-C motif chemokine 1 (CXCL1)/GROα and the adhesion molecule E-selectin in glomerular endothelial cells (GECs) play a pivotal role in the development of GN. Endothelial Toll-like receptor 3 (TLR3) is thought to be involved in the inflammatory response via innate immunity. However, the role of endothelial TLR3 signaling in the expression of neutrophil chemoattractants and adhesion molecules remains to be elucidated. Thus, we aimed to examine this issue. METHODS: We treated normal human GECs with polyinosinic-polycytidylic acid (poly IC), an authentic double-stranded RNA, and analyzed the expressions of CXCL1 and E-selectin using quantitative real-time reverse transcription-polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. To further elucidate the poly IC-induced signaling pathway, we subjected the cells to RNA interference against TLR3, interferon (IFN)-ß, nuclear factor (NF)-κB p65, and IFN regulatory factor (IRF) 3. We also used immunofluorescence to examine the endothelial expression of CXCL1 in biopsy specimens from patients with crescentic and non-crescentic purpura nephritis (PN). RESULTS: We found that the activation of TLR3 induced the endothelial expression of CXCL1 and E-selectin, and that this involved TLR3, -NF-κB, IRF3, and IFN-ß. Intense endothelial CXCL1 expression was observed in biopsy specimens from patients with crescentic PN. CONCLUSION: These findings support a role for glomerular antiviral innate immunity in the pathogenesis of GN. Intervention of glomerular TLR3 signaling may therefore be a suitable therapeutic strategy for treating GN in the future.

Long-term clinicopathologic observation in a case of steroid-resistant nephrotic syndrome caused by a novel Crumbs homolog 2 mutation.

Recent advances in high-throughput sequencing for clinical genetic testing have revealed novel disease-causing genes, such as Crumbs homolog 2 (CRB2) for early-onset steroid-resistant nephrotic syndrome (SRNS). We report the long-term clinicopathologic observation of a Japanese female patient with SRNS caused by a newly identified compound heterozygous mutation of CRB2 (p.Arg628Cys and p.Gly839Trp located in the 10th and 11th epidermal growth factor-like domains, respectively). She was initially examined during a mass urinary screening for 3.5-year-old children in Japan. Although she developed long-standing SRNS without any extrarenal clinical signs thereafter, her renal function was well-preserved over the next 17 years. In total, six sequential renal biopsy specimens revealed histologic alterations ranging from minor glomerular abnormalities to advanced focal segmental glomerulosclerosis (FSGS). A genetic analysis for SRNS performed at 19 years of age revealed a newly identified compound heterozygous mutation in CRB2. Glomerular CRB2 immunoreactivity in biopsy specimens from the patient was scanty, whereas intense expression was observed in those from patients with idiopathic FSGS or in controls. To our knowledge, this is the first report regarding a long-term outcome in a case of SRNS due to an identified CRB2 mutation. Although the phenotype of CRB2 mutation-related syndrome is now expanding, we believe that this case might provide a novel clinicopathologic aspect of this syndrome.

Cylindromatosis (CYLD), a Deubiquitinase, Attenuates Inflammatory Signaling Pathways by Activating Toll-Like Receptor 3 in Human Mesangial Cells.

BACKGROUND/AIMS: Cylindromatosis (CYLD), a deubiquitinase, negatively regulates nuclear factor-κB in various cells. However, its potential roles in glomerular inflammation remain unclear. Because the activation of the Toll-like receptor 3 (TLR3)/type I interferon (IFN) pathways plays a pivotal role in chronic kidney diseases (CKD), we examined the role of CYLD in the TLR3 signaling in cultured human mesangial cells (MCs). METHODS: We stimulated CYLD-silenced MCs with polyinosinic-polycytidylic acid (poly IC), a synthetic analogue of dsRNA, and studied representative TLR3/IFN-ß pathways (i.e., TLR3/IFN-ß/retinoic acid-inducible gene-I (RIG-I)/CCL5, and TLR3/IFN-ß/melanoma differentiation associated gene 5 (MDA5)/CXCL10 axes) using RT-PCR, western blotting, and ELISA. We also used immunofluorescence staining and microscopy to examine mesangial CYLD expression in biopsied specimens from patients with CKD. RESULTS: CYLD silencing resulted in an increase of poly IC-induced RIG-I and MDA5 protein levels and increased CCL5 and CXCL10 mRNA and protein expression, but unexpectedly decreased mRNA expressions of RIG-I and MDA5. Interestingly, CYLD silencing did not affect IFN-ß or the phosphorylated STAT1 (signal transducers and activator of transcription protein 1). CYLD was highly expressed in biopsied specimens from patients with proliferative lupus nephritis (LN). CONCLUSION: CYLD inhibits post-transcriptional regulation of RIG-I and MDA5 expression following TLR3 activation in MCs. CYLD may be involved in the pathogenesis of CKD, especially pathogenesis of LN.

Urinary excretion of sphingomyelinase phosphodiesterase acid-like 3b in children with intractable nephrotic syndrome.

Rituximab (RTX), a specific antibody to human CD20, has been successfully used to treat intractable nephrotic syndrome (NS). Recent studies have suggested a direct effect of RTX on podocytes by targeting sphingomyelinase phosphodiesterase acid-like 3b (SMPDL-3b). Thus, we examined the urinary excretion of SMPDL-3b as well as its immunoreactivity in biopsy specimens from children with intractable NS. Urine samples from six patients (five with minimal-change NS and one with focal segmental glomerulosclerosis) and from four healthy adults were examined. Glomerular immunoreactivity and urinary excretion of SMPDL3b in proteinuric NS patients decreased compared with controls. Interestingly, urine samples obtained from the same patients at the remission stage after RTX treatment showed an increase in urinary SMPDL-3b excretion compared with the proteinuric stage. Urinary excretion level of SMPDL-3b could thus be used to predict the clinical efficacy of RTX treatment in NS patients.

Rebamipide reduces amyloid-ß 1-42 (Aß42) production and ameliorates Aß43-lowered cell viability in cultured SH-SY5Y human neuroblastoma cells.

Amyloid-beta (Aß) peptides, Aß 1-42 (Aß42) and Aß43, in particular, have been implicated in the pathophysiology of neurodegenerative disease such as Alzheimer's disease (AD). Rebamipide (REB), a gastrointestinal protective drug, can cross the blood-brain barrier after oral administration; however, the effects of REB on neuronal cells have not yet been reported. In this study, we investigated the effects of REB on Aß43-induced cytotoxicity (monomers, 10µM) in cultured SH-SY5Y human neuroblastoma cells. Addition of REB (10-1000nM) into the media partially ameliorated the reduced cell viability observed after Aß43 treatment, which was determined by the MTT assay. REB reduced the levels of intracellular Aß oligomers (100-150kDa) that were formed from the exogenous addition of Aß43 monomers. In addition, REB (30nM) reduced endogenous Aß42 secretion, which was analyzed by the enzyme-linked immunosorbent assay. Furthermore, REB enhanced the expression of tumor necrosis factor-α-converting enzyme/a disintegrin and metalloproteinase-17, neprilysin, matrix-metalloproteinase-14 (MMP-14)/membrane type-1 MMP, cyclooxygenase-2, and sirtuin 1, even in cells challenged with Aß43. These results suggest that REB improves the cell viability by inducing genes that regulate Aß levels and also genes that are cytoprotective. The secondary use of REB may have potential in the prevention of Aß-mediated diseases, particularly AD.

Chloroquine attenuates TLR3/IFN-ß signaling in cultured normal human mesangial cells: A possible protective effect against renal damage in lupus nephritis.

BACKGROUND: Chloroquine has been reported to protect against renal damage in lupus nephritis (LN); however, its detailed mechanism in glomerular inflammation remains unclear. Upregulation of the type-I interferon (IFN) system plays a pivotal role in LN pathogenesis, therefore, we examined whether chloroquine inhibits toll-like receptor 3 (TLR3)/IFN-ß signaling in cultured normal human mesangial cells (MCs). METHODS: We examined chloroquine effect on the representative TLR3/IFN-ß-signaling axis, TLR3/IFN-ß/retinoic acid-inducible gene-I (RIG-I)/CCL5 in MCs treated with polyinosinic-polycytidylic acid (poly IC), a synthetic viral dsRNA analog and analyzed the expression of these molecules using reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). Furthermore, we subjected MCs to RNA interference against NF-κB p65. RESULTS: Pretreatment of cells with chloroquine attenuated IFN-ß, RIG-I and CCL5 expression and phosphorylation of STAT1 induced by poly IC, but not IFN-ß-induced phosphorylation of STAT1 and RIG-I expression induced by IFN-ß. Knockdown of p65 inhibited the poly IC-induced IFN-ß expression, and chloroquine pretreatment decreased the nuclear poly IC-induced translocation of NF-κB p65 in MCs. CONCLUSION: These results suggest that chloroquine attenuates mesangial TLR3 signaling in the early phase of NF-κB activation. Considering that TLRs/type-I IFNs signaling is implicated in LN pathogenesis, our results may further support regional renoprotective effects of chloroquine in treating LN.

Clarithromycin attenuates the expression of monocyte chemoattractant protein-1 by activating toll-like receptor 4 in human mesangial cells.

BACKGROUND: Signaling pathways induced by the activation of renal toll-like receptor 4 (TLR4) play a pivotal role in chronic kidney disease (CKD). Some recent studies suggested that clarithromycin (CAM), a 14-membered ring macrolide, exerts renoprotective effects by suppressing proinflammatory chemokines. However, its beneficial effects on signaling pathways through renal TLR4 activation are unknown. METHODS: Cultured human mesangial cells (MCs) were treated with lipopolysaccharide (LPS). Expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and interleukin-8 (IL-8/CXCL8) was analyzed by quantitative RT-PCR and enzyme-linked immunosorbent assay. Signaling pathways affected by CAM were determined by examining the activation of nuclear factor-κB (NF-κB) and p38 mitogen-activated protein kinase (MAPK) by performing western blotting. RESULTS: CAM inhibited both the mRNA and protein expression of MCP-1 without cell injury but did not affect those expressions of IL-8 in LPS-stimulated MCs. Interestingly, CAM decreased p38 MAPK activation by inhibiting phosphorylation but did not affect NF-κB activation. CONCLUSION: Our results indicated that CAM exerted renoprotective effects by suppression of p38 MAPK activity and by decreasing the expression of MCP-1 in LPS-stimulated MCs. Given the implication of TLR4 signaling in CKD, CAM may be a potential treatment of choice for CKD.

Monitoring of Epstein-Barr virus load and killer T cells in patients with juvenile idiopathic arthritis treated with methotrexate or tocilizumab.

OBJECTIVES: Methotrexate (MTX) is used for the treatment of polyarticular juvenile idiopathic arthritis (JIA), and an anti-interleukin-6 receptor monoclonal antibody (tocilizumab: TCZ) is also used and added for the treatment of intractable JIA. It has been reported that MTX might induce Epstein-Barr virus (EBV)-associated lymphoma, but the discussion about the effect of MTX and/or TCZ against reactivation of EBV in pediatric patients has been incomplete. METHODS: The EBV loads in four polyarticular JIA and three systemic arthritis JIA patients treated with MTX and/or TCZ, and the percentage of EBV-specific killer T cells (EBV-CTLs) in some patients were prospectively monitored. RESULTS: No patients had EBV-associated symptoms during the observation period. EBV loads in all patients were not significantly increased, and the levels of EBV loads were the same as EBV-seropositive healthy children following the administration of MTX and/or TCZ. EBV-CTLs were detectable during the observation period, but some patients had slightly low levels of EBV-CTLs. CONCLUSION: Treatment with MTX and/or TCZ did not severely affect EBV load and prevent induction of EBV-CTLs in JIA patients.

Dysgerminoma developing from an ectopic ovary in a patient with WAGR syndrome: A case report.

WAGR syndrome is caused by an 11p13 deletion and includes Wilms' tumor, aniridia, genitourinary anomalies and mental retardation. We encountered a case of a dysgerminoma originating in an ectopic ovary in a woman with WAGR syndrome. Our patient was a 24-year-old nulliparous woman who was diagnosed with WAGR syndrome. The patient had undergone left nephrectomy for a Wilms' tumor and postoperative chemotherapy at the age of 7 months. She also had a history of glaucoma surgery in both eyes, and was followed up at the Department of Pediatrics for diabetes mellitus, hypertension, liver dysfunction and hyperuricemia. The patient was investigated for oliguria and had elevated levels of blood urea nitrogen (45 mg/dl) and creatinine (5.4 mg/dl); she was admitted to the hospital with acute renal failure and a computed tomography scan revealed a pelvic tumor with a long axis of 10 cm that was obstructing the right ureter. Following insertion of a ureteral stent, the tumor was removed. The tumor had developed in the retroperitoneal space independent of the ovaries. The right adnexa were normal. The tumor was histopathologically diagnosed as dysgerminoma. Follicles were found in part of the tumor; it was thus hypothesized that the tumor developed from an ectopic ovary. The patient was administered etoposide after surgery, and has been recurrence-free for 4 years since treatment.

Interferon (IFN)-Induced Protein 35 (IFI35), a Type I Interferon-Dependent Transcript, Upregulates Inflammatory Signaling Pathways by Activating Toll-Like Receptor 3 in Human Mesangial Cells.

BACKGROUND/AIMS: Activation of Toll-like receptor 3 (TLR3) signaling followed by type I interferon (IFN) expression is crucial in antiviral and "pseudoviral" immune reactions in renal mesangial cells (MCs). These reactions are probably involved in the pathogenesis of chronic kidney disease (CKD). However, the role of IFN-induced 35-kDa protein 35 (IFI35), a type I IFN-dependent transcript, in glomerular inflammation is unclear. Here, we aimed to investigate the expression and the role of IFI35 in IFN-ß/retinoic acid-inducible gene-I (RIG-I)/CCL5 and IFN-ß/melanoma differentiation-associated gene 5 (MDA5)/CXCL10 axes in MCs. METHODS: We treated human MCs with polyinosinic-polycytidylic acid (poly IC), an authentic double-stranded RNA, then analysed the IFI35 expression by reverse transcription-polymerase chain reaction and western blotting. To examine the regulation of IFI35 expression, we subjected MCs to RNA interference (siRNA) against IFN-ß, RIG-I, and MDA5. RESULTS: Activation of TLR3 by poly IC induces the IFI35 expression in MCs. siRNA against IFN-ß inhibited poly IC-induced IFI35 expression. Knockdown of IFI35 resulted in a decrease of poly IC-induced RIG-I and MDA5 protein as well as decreased CCL5 and CXCL10 mRNA and protein expression. However, it did not affect the expression of none of phosphorylated signal transducers or activator of transcription (STAT) 1 protein, or RIG-I and MDA5 in mRNA levels. CONCLUSION: Regional expression of IFI35 and its dysregulation may be involved in the pathogenesis of glomerular inflammation in CKD.

Does Dent disease remain an underrecognized cause for young boys with focal glomerulosclerosis?

Focal glomerulosclerosis (FGS) is a histologic entity that causes significant proteinuria in children. Although its etiology varies, recent reports indicated that some young male patients with FGS had underlying Dent disease. We describe the case of a 14-year-old Japanese boy who presented with persistent non-nephrotic range proteinuria, hematuria, and renal insufficiency. The patient was initially diagnosed as having FGS associated with scattered tubulointerstitial fibrosis. Although he had neither nephrocalcinosis nor family history of renal disease including urolithiasis, increased excretion of urinary ß2 microglobulin was noted. Genetic analysis for Dent disease indicated a mutation (c.726 + 1G > A) in Chloride Channel, Voltage-Sensitive 5 (CLCN5). Given a recent hypothesis that Dent disease may be underrecognized in children with FGS, a careful diagnostic evaluation for possible underlying Dent disease should be considered in young boys who present with persistent albuminuria associated with high-grade low-molecular-weight proteinuria.

Interferon-Stimulated Gene 15, a Type I Interferon-Dependent Transcript, Is Involved in a Negative Feedback Loop in Innate Immune Reactions in Human Mesangial Cells.

BACKGROUND: Since innate immunity plays a pivotal role in the pathogenesis of glomerulonephritis, the activation of toll-like receptor (TLR) 3/type I interferon (IFN) cascades is important in glomerular inflammation. However, the role of IFN-stimulated gene 15 (ISG15), a type IFN-dependent transcript, in glomerular inflammation is unclear. We, therefore, examined the role of ISG15 in innate immune reactions induced by TLR3 signaling in cultured human mesangial cells (MCs). METHODS: We treated MCs with polyinosinic-polycytidylic acid (poly IC), an authentic double-stranded RNA, and analyzed the ISG15 expression by reverse transcription-polymerase chain reaction and western blotting. To examine the regulation of ISG15 expression, we subjected MCs to RNA interference (siRNA) against TLR3, IFN-ß, ISG56, and melanoma differentiation-associated gene 5 (MDA5). RESULTS: ISG15 expression induced by poly IC in MCs was inhibited by siRNA against TLR3 and IFN-ß, whereas silencing of ISG56 or MDA5 had no effect. A knockdown of ISG15 upregulated the expression of ISG56, MDA5, CXCL10 and phosphorylated signal transducers and activators of transcription protein 1 (P-STAT1), while a knockdown of ubiquitin-like modifier activating enzyme 7, a key enzyme that conjugates ISG15 to target proteins, did not affect the expression. Knockdown of ubiquitin specific protease 18, an ISG15 isopeptidase, also upregulated P-STAT1, ISG56, MDA5 and CXCL10. CONCLUSION: Since unconjugated free ISG15 negatively regulates the phosphorylation of STAT1 and its downstream reactions, ISG15 dysregulation may be involved in the pathogenesis of glomerular inflammation. We believe that suitable interventions in these innate immune cascades is desirable for the future therapeutic strategies for glomerulonephritis.

Expressions of mRNA for innate immunity-associated functional molecules in urinary sediment in immunoglobulin A nephropathy.

AIM: It has been reported that the innate immune system plays a pivotal role in the pathogenesis of immunoglobulin A nephropathy (IgAN). To explore non-invasive monitoring of disease activity in children with IgAN, we examined whether expressions of mRNA for innate immunity-associated functional molecules: CC ligand chemokine 5 (CCL5), fractalkine/CX3CL1, interferon-γ-induced protein 10 (IP-10), monocyte chemoattractant protein 1 (MCP-1), retinoic acid-inducible gene-I (RIG-I), and toll-like receptor 3 (TLR3) in urinary sediment from patients with IgAN correlate with histologic parameters. METHODS: Twenty consecutive children with IgAN and four children with thin basement membrane disease (serving as a non-inflammatory control) were enrolled in this pilot study. Urinary mRNA expressions of target genes were examined real-time quantitative polymerase chain reaction. RESULTS: The expressions of CCL5, fractalkine and RIG-I were significantly increased in IgAN (all P < 0.05). Although no significant correlation was observed between mRNA expressions of these three molecules and clinical parameters, such as levels of urinary protein excretion, degrees of occult blood in urine and serum albumin, the expression of fractalkine was significantly correlated with the histological activity index (P = 0.022) and the chronicity index (P = 0.005). Furthermore, intense glomerular immune activity of fractalkine was observed in biopsy specimens in patients with moderately to severe proliferative IgAN. CONCLUSION: Regional expression of fractalkine may be involved in the pathogenesis of childhood IgAN. Although our present findings remain preliminary, measurement of mRNA expression of fractalkine in urinary sediment could be used as a non-invasive method for predicting histologic severity in IgAN in children. Further studies of this issue are needed.

Alteration in the podoplanin-ezrin-cytoskeleton linkage is an important initiation event of the podocyte injury in puromycin aminonucleoside nephropathy, a mimic of minimal change nephrotic syndrome.

Podoplanin was identified as a protein associated with the transformation of arborized foot processes of glomerular epithelial cells (podocytes) to flat feet. However, the function of podoplanin in the podocyte is not yet fully clarified. In this study, we analyzed the molecular nature of podoplanin, and its expression in rat nephrotic models and patients with minimal change nephrotic syndrome (MCNS). We demonstrated here that podoplanin has two forms: one contains abundant sialic acid and the other a lesser amount of sialic acid. Podoplanin bound ezrin to interact with the cytoskeleton. The silencing of podoplanin in cultured podocytes caused a change in the cell shape and the distribution of ezrin and actin. The expression of podoplanin was clearly reduced before the onset of proteinuria in puromycin aminonucleoside (PAN) nephropathy, a mimic of MCNS, and the decrease in the expression of podoplanin became more evident at the proteinuric stage. Podoplanin was detected in normal urine samples, and the amount of urinary podoplanin markedly increased on day 1 of PAN nephropathy. Urinary ezrin was also detected. The amount of the phosphorylated ezrin was reduced, while the amount of the podoplanin-interacting ezrin increased. The podoplanin expression was reduced in a patient with active-phase MCNS. It is conceivable that the alteration of the podoplanin-ezrin-cytoskeleton linkage is an important event of the podocyte injury in MCNS.

Severe intrinsic acute kidney injury associated with therapeutic doses of acetaminophen.

Acetaminophen is a commonly used medication to manage fever and pain in children and the drug is generally considered to be safe when used at appropriate therapeutic dosages. Recently, we encountered the case of a 3-year-old Japanese girl who suffered from severe intrinsic acute kidney injury (AKI) after therapeutic doses of acetaminophen for a fever due to viral infection. Renal biopsy indicated severe acute tubular necrosis with a significant striped interstitial fibrosis and mild interstitial inflammation. Unfortunately, she developed chronic kidney disease thereafter. This is the youngest case of biopsy-proven severe intrinsic AKI associated with therapeutic doses of acetaminophen. Acetaminophen, even if administered at therapeutic dosages, may be dangerous in selected children, especially with possible pre-existing volume depletion.

Mizoribine in the treatment of pediatric-onset glomerular disease.

BACKGROUND: Mizoribine (MZR) is a selective inhibitor of inosine monophosphate dehydrogenase, a key enzyme in the pathway responsible for de novo synthesis of guanine nucleotides. As an immunosuppressant, MZR has been used successfully without any serious adverse effects in the treatment of renal diseases in children as well as adults. Besides its immunosuppressive effect, MZR has been reported to ameliorate tubulointerstitial fibrosis in rats via suppression of macrophage infiltration. DATA SOURCES: In this review, we summarize reported possible benefits of MZR in the treatment of pediatriconset glomerular disease. RESULTS: We recently observed that MZR itself selectively attenuates the expression of monocyte chemoattractant protein-1 at both the mRNA and protein levels in human mesangial cells. Since MZR binds specifically to 14-3-3 proteins and heat shock protein 60, both of which are reportedly expressed in inflamed glomeruli, MZR may bind directly to inflamed glomerular cells, thereby possibly preventing progressive damage from glomerulonephritis through a suppressive effect on activated macrophages and intrinsic renal cells. Moreover, it has recently been reported that MZR directly prevents podocyte injury through correction of the intracellular energy balance and nephrin biogenesis in cultured podocyte and rat models, suggesting a direct anti-proteinuric effect of MZR. CONCLUSIONS: These beneficial mechanisms of action of MZR as well as its immunosuppressive effect would warrant its use in the treatment of pediatric-onset glomerular disease. Although further studies remain to be done, we believe that MZR may be an attractive treatment of choice for children with glomerular diseases from a histologic as well as clinical standpoint.