Validity of the Oxford classification of IgA nephropathy in children

BACKGROUND

In 2009, the Oxford classification of IgA nephropathy was published. However, its validity has not been fully examined in children. This study aimed to assess this system in an independent large-scale cohort of children.

METHODS

We analyzed 161 consecutive children with newly diagnosed IgA nephropathy from 1977 to 1989 retrospectively. We examined the ability of each variable in the Oxford classification as a predictor of renal outcome defined as ≥ stage III chronic kidney disease (CKD) (estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2)) using Cox regression analysis.

RESULTS

The mean mesangial score, and ratios of segmental glomerulosclerosis, endocapillary hypercellularity, tubular atrophy, and crescents were 0.49, 0.8%, 13.1%, 3.3%, and 9.2% respectively. Seven cases reached ≥ stage III CKD. In univariate analyses, mesangial hypercellularity score, endocapillary hypercellularity, tubular atrophy, and crescents were significant predictors of renal outcome. In a multivariate analysis, only mesangial hypercellularity score, tubular atrophy, and crescents were significant though, depending on models. Segmental glomerulosclerosis was not a significant predictor of renal outcome. Although the significance of crescents was not addressed in the Oxford classification, crescents were important predictors of outcome.

CONCLUSIONS

The Oxford classification appears to be valid for predicting renal outcome in children.

[FTY720 attenuates rat anti-Thy-1 mesangial proliferative glomerulonephritis by inhibition of transforming growth factor β1-connective tissue growth factor pathway]

OBJECTIVE

To investigate whether FTY720 inhibits rat mesangial proliferation and extracellular matrix expansion through suppression of transforming growth factor β1-connective tissue growth factor (TGFβ1-CTGF) pathway, and to explore experimental evidence for its effect on mesangial proliferative glomerulonephritis.

METHODS

A rat model of anti-Thy-1 mesangial proliferative glomerulonephritis was established and FTY720 intervention was performed. Periphery blood lymphocyte count, urine protein excretion, glomerular mesangial proliferation, protein and gene expression of TGFβ1 and CTGF and extracellular matrix protein including fibronectin, laminin and collagen IV in isolated glomeruli were documented at 1, 3 and 7 days after injection of anti-Thy-1 antibody.

RESULTS

The model group developed proteinuria at 1, 3 and 7 days after injection of anti-Thy-1 antibody, which were significantly higher [(27.9 ± 7.3), (63.5 ± 18.8) and (52.4 ± 15.4)mg/d, respectively] than those in the control group [(8.4 ± 2.4), (8.4 ± 2.1) and (10.4 ± 3.2) mg/d; respectively, P < 0.01]. FTY720 intervention group showed significantly decreased proteinuria at 3 and 7 days after injection [(31.4 ± 7.0), (25.5 ± 7.7) mg/d, respectively] than model group (P < 0.01), although higher than the control group (P < 0.01). After intervention for 3 and 7 days, FTY720 significantly down-regulated both TGFβ1 and CTGF gene and protein expression in cultured glomeruli, and suppressed the production of glomerular extracellular matrix protein secretion, leading to attenuated mesangial cell proliferation and extracellular matrix expansion in rat anti-Thy-1 mesangial proliferative glomerulonephritis.

CONCLUSION

FTY720 significantly attenuates mesangial proliferation and extracellular matrix expansion through inhibition of TGFβ1-CTGF pathway in rat, and thus ameliorates the development of anti-Thy-1 mesangial proliferative glomerulonephritis.

Coexistence of fibrillary glomerulonephritis in a patient with multiple myeloma

A 71-year-old man was admitted to our hospital for two weeks due to edema in both legs. A bone marrow aspiration test confirmed a diagnosis of multiple myeloma. The result of the patient's renal biopsy showed fibrillary glomerulonephritis (FGN). FGN is a rare form of glomerulopathy that is diagnosed using electron microscopy when deposits of amyloid-like fibrils are observed on the mesangium and microvascular wall. These fibrils do not respond to Congo red staining and are generally 12-30 nm in diameter. This is a report of an unusual case of fibrillary glomerulonephritis in a patient with multiple myeloma.

[Effect of losartan on acute renal failure induced by severe ethylene glycol poisoning in rats]

The effect of an angiotensin receptor II antagonist (losartan) on the model acute renal failure (ARF) induced by severe ethylene glycol poisoning at 2/3 LD50 has been studied in rats. It is established that losartan administration (20 mg/kg for 72 h) produces a significant (4-fold) increase in the animal death rate, which is associated with ARF transition to a decompensation stage. Pronounced changes in the qualitative and quantitative composition of diurnal diuresis, more than 8-fold increase in the creatinine level, and 18-fold increase in the blood urea have been observed. Thus, the administration of losartan to ethylene glycol poisoned rats causes more pronounced degeneration of proximal tubule epithelium and destruction of glomeruli. It is concluded that the use of losartan for the treatment of ARF is inexpedient.

Myeloperoxidase anti-cytoplasmic antibody related crescentic glomerulonephritis in a patient with IgG3λ monoclonal immunoglobulin deposition disease with membranous features

A 68-year-old woman showed rapidly progressive glomerulonephritis based on the fact that she had 1+ proteinuria (1.1 g/day), a 3+ occult blood reaction, blood urea nitrogen of 32.4 mg/dL, serum creatinine of 2.96 mg/dL, and myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibodies (ANCA) at 52 ELISA Unit (normal range: below 10). A renal biopsy demonstrated a bubbling appearance associated with cellular crescent formation with segmental necrosis. Immunofluorescence studies showed granular IgG3λ deposition along the basement membrane and in the mesangial area. This is the first English-language case report describing MPO-ANCA positive crescentic glomerulonephritis in a patient demonstrating monoclonal immunoglobulin deposition disease with mainly membranous features.

[Therapeutic apheresis in idiopathic nephrotic syndrome]

Idiopathic nephrotic syndrome (INS) is characterized by diffuse foot process effacement on electron microscopy and minimal changes (called minimal change nephropathy [MCN]), focal segmental glomerular sclerosis (FSGS), or the mesangial variant with proliferation on light microscopy. No evidence of immune deposits is seen. MCN is the most common form of INS in children and is sensitive to corticosteroid therapy in 90% of cases. FSGS accounts for 20-30% of biopsy-proven glomerulopathies in adult patients. Fifty percent of drug-resistant patients develop terminal renal failure in 6-8 years. Moreover, FSGS reappears in 15-50% of cases after the first transplant and in a higher percentage after the second graft. Genetic forms of INS, with mutation of the NPHS1 and NPHS2 genes encoding nephrin and podocin, are mostly steroid resistant and very rarely recur in the transplant. On the basis of any clinical pattern they are indistinguishable from idiopathic forms. Sera from patients with FSGS may contain some proteinuric or permeability factors (PFs), which have been partially identified and are predictive of recurrence in kidney grafts. Removal of PFs by means of plasmapheresis or plasma immunoadsorption by protein A or LDL apheresis has been associated with proteinuria reduction in cases of FSGS both of native and transplanted kidneys, in small series or cohort studies described by many authors. In this review of the main studies we will analyze the results of the apheretic treatments and the role of some clinical, serological and histological parameters in determining the outcome of patients.

Early intensive insulin therapy attenuates the p38 pathway in the renal cortex and indices of nephropathy in diabetic rats

In this rodent study, we compared the effects of early versus late intensive insulin therapy on diabetic nephropathy and potential causal mechanisms. Diabetes was induced in rats by high-fat diet and low-dose streptozotocin. Intensive insulin therapy was initiated in the early intensive insulin therapy groups as soon as diabetes was confirmed and lasted for 8 (8wEI group) and 16 weeks (16wEI group). In the late insulin therapy group (LI group), intensive insulin treatment was initiated 8 weeks later and lasted for 8 weeks. Age-matched diabetic rats (8wDM group and 16wDM group) and non-diabetic rats (8wNC group and 16wNC group) served as controls. Histological analysis, real-time PCR, and western blot were performed in renal cortex specimens. Glomerular hypertrophy and mesangial matrix expansion were prominent in the 16wDM and LI groups while the EI groups remained normal and similar to the 16wNC group. Western blots revealed that p38 MAPK activities in the EI groups decreased significantly, whereas the level in the LI group was markedly higher than the 16wEI group, and not different from the DM groups. Activities of MKK3/6, CREB and MKP-1 proteins as well as CREB and MKP-1 mRNA showed a similar pattern. Therefore, we concluded that early intensive insulin treatment and attainment of good glycemic control counteracted some renal molecular pathways associated with epigenetic metabolic memory to minimize risk of diabetic nephropathy. However, late insulin therapy did not abrogate the increased renal cortical p38 MAPK pathway activation in diabetic rats and led to glomerular hypertrophy and extracellular matrix expansion.

Deletion of platelet-derived growth factor receptor-β improves diabetic nephropathy in Ca²⁺/calmodulin-dependent protein kinase IIα (Thr286Asp) transgenic mice

AIMS/HYPOTHESIS

The activation of platelet-derived growth factor receptor-β (PDGFR-β) signalling is increased in the glomeruli and tubules of diabetic animals. In this study, we examined the role of PDGFR-β signalling during the development of diabetic nephropathy.

METHODS

We recently generated pancreatic beta cell-specific Ca(2+)/calmodulin-dependent protein kinase IIα (Thr286Asp) transgenic mice (CaMKIIα mice), which show very high plasma glucose levels up to 55.5 mmol/l and exhibit the features of diabetic nephropathy. These mice were crossed with conditional knockout mice in which Pdgfr-β (also known as Pdgfrb) was deleted postnatally. The effect of the deletion of the Pdgfr-β gene on diabetic nephropathy in CaMKIIα mice was evaluated at 10 and 16 weeks of age.

RESULTS

The plasma glucose concentrations and HbA(1c) levels were elevated in the CaMKIIα mice from 4 weeks of age. Variables indicative of diabetic nephropathy, such as an increased urinary albumin/creatinine ratio, kidney weight/body weight ratio and mesangial area/glomerular area ratio, were observed at 16 weeks of age. The postnatal deletion of the Pdgfr-β gene significantly decreased the urinary albumin/creatinine ratio and mesangial area/glomerular area ratio without affecting the plasma glucose concentration. Furthermore, the increased oxidative stress in the kidneys of the CaMKIIα mice as shown by the increased urinary 8-hydroxydeoxyguanosine (8-OHdG) excretion and the increased expression of NAD(P)H oxidase 4 (NOX4), glutathione peroxidase 1 (GPX1) and manganese superoxide dismutase (MnSOD) was decreased by Pdgfr-β gene deletion.

CONCLUSIONS/INTERPRETATION

The activation of PDGFR-β signalling contributes to the progress of diabetic nephropathy, with an increase in oxidative stress and mesangial expansion in CaMKIIα mice.

[Fibrillary glomerulonephritis and immunotactoid glomerulopathy: case reports]

Fibrillary glomerulonephritis and immunotactoid glomerulopathy belong to the rare renal disorders characterized by formation of the organized glomerular deposits. Pathogenesis of these disorders is still not fully clarified but they could appear as a primary condition or be regarded as a part of the various systemic mainly lymphoproliferative disorders. Clinical presentation includes proteinuria, hematuria, arterial hypertension and progressive renal insufficiency during several years. In this work we presented a male patient with fibrillary glomerulonephritis and a female patient with immunotactoid glomerulopathy as a part of a non-Hodgkin lymphoma. The aim of this presentation is to show the features of the fibrillary glomerulonephritis and immunotactoid glomerulopathy as well as emphasize the significance of the electron microscopy in the identification of these uncommon entities.

Renal thrombotic microangiopathy in mice with combined deletion of endocytic recycling regulators EHD3 and EHD4

Eps15 Homology Domain-containing 3 (EHD3), a member of the EHD protein family that regulates endocytic recycling, is the first protein reported to be specifically expressed in the glomerular endothelium in the kidney; therefore we generated Ehd3(-/-) mice and assessed renal development and pathology. Ehd3(-/-) animals showed no overt defects, and exhibited no proteinuria or glomerular pathology. However, as the expression of EHD4, a related family member, was elevated in the glomerular endothelium of Ehd3(-/-) mice and suggested functional compensation, we generated and analyzed Ehd3(-/-); Ehd4(-/-) mice. These mice were smaller, possessed smaller and paler kidneys, were proteinuric and died between 3-24 weeks of age. Detailed analyses of Ehd3(-/-); Ehd4(-/-) kidneys demonstrated thrombotic microangiopathy (TMA)-like glomerular lesions including thickening and duplication of glomerular basement membrane, endothelial swelling and loss of fenestrations. Other changes included segmental podocyte foot process effacement, mesangial interposition, and abnormal podocytic and mesangial marker expression. The glomerular lesions observed were strikingly similar to those seen in human pre-eclampsia and mouse models of reduced VEGF expression. As altered glomerular endothelial VEGFR2 expression and localization and increased apoptosis was observed in the absence of EHD3 and EHD4, we propose that EHD-mediated endocytic traffic of key surface receptors such as VEGFR2 is essential for physiological control of glomerular function. Furthermore, Ehd3(-/-); Ehd4(-/-) mice provide a unique model to elucidate mechanisms of glomerular endothelial injury which is observed in a wide variety of human renal and extra-renal diseases.

Histological changes and immunohistochemical markers in the assessment of glomerulosclerosis in patients with glomerulonephritis

INTRODUCTION

Glomerular cells (mesangial, endothelial, epithelial) are activated during glomerulonephritis, a process indicated by the expression of the immunohistochemical marker α-smooth muscle actin (SMA). Many growth factors participate in the above-mentioned processes, among them of great importance is the transforming growth factor β (TGF-β). The result of these changes is represented by active lesions (mesangial matrix increase, mesangial cell proliferation) and chronic fibrotic lesions (glomerulosclerosis).

METHODOLOGY

We studied a group of 41 patients with primary and secondary glomerulonephritis (24 males, 17 females, mean age 45.5 ± 12.9 years), which underwent kidney biopsies, processed in light microscopy. We performed immunohistochemistry procedures with monoclonal antibodies (performed with the LSAB2-HRP system: anti-α-SMA, and anti-TGF-β), which were assessed using a semiquantitative score, that was correlated with the histological and biological data. In order to quantify the histological changes and to assess the extent of active-inflammatory and chronic-sclerotic/fibrotic lesions, we adapted a scoring system initially used only for lupus nephritis, and ANCA-associated vasculitis.

RESULTS

TGF-β expression in glomerular endothelial cells correlated with mesangial matrix increase (r=0.28, p<0.05), total activity index (r=0.29, p<0.05) and total chronicity index (r=0.34, p<0.05). Glomerular epithelial cell TGF-β correlates with mesangial proliferation (r=0.29, p<0.05), mesangial matrix increase (r=0.4, p<0.01) and total activity index (r=0.28, p<0.05). We observed a strong correlation between endothelial immunolabeling of SMA and the mesangial proliferation score (r=-0.96, p<0.005) and also an indirect correlation with the glomerulosclerosis score (r=-0.35, p<0.05) and the total chronicity index (r=-0.39, p<0.05). Concerning biological data there was a correlation between mesangial SMA expression and serum creatinine (r=0.60, p<0.001) and an indirect correlation with GFR (r=-0.37, p<0.05).

CONCLUSIONS

We conclude that TGF-β has a key role in determining glomerulosclerosis especially through mesangial matrix increase, but possibly also through mesangial cells proliferation. Another role of this growth factor is related to transdifferentiation, not only epithelial-mesenchymal, but also endothelial-mesenchymal.

Beneficial effects of C-peptide on renal morphology in diabetic rats

The study was undertaken to examine the effects of C-peptide on glomerular volume (V(GLOM)), mesangial matrix synthesis, and degradation in streptozotocin (STZ)-diabetic rats with poor or moderate glycemic control. Series 1 (poor glycemic control) included groups of healthy rats, hyperglycemic rats, diabetic insulin-treated rats and diabetic C-peptide-treated rats. Series 2 (moderate glycemic control) included groups of healthy rats, diabetic insulin-treated rats, diabetic insulin- and C-peptide-treated rats. After 8 weeks, the left kidney was excised for evaluation of V(GLOM) and mesangial matrix area via light microscopy. Mesangial cells were cultured for 48 h and type IV collagen expression and matrix metalloproteinase (MMP)-2 expression were measured by ELISA and RT-PCR. The results indicated that in Series 1, C-peptide administration suppressed the diabetes-induced increase in the V(GLOM) and the mesangial matrix area. In Series 2, C-peptide administration resulted in a similar decrease in the V(GLOM) and a greater decrease in the mesangial matrix area when compared with insulin therapy alone. Moreover, C-peptide (300 nM) completely inhibited the glucose-induced increase of the collagen IV mRNA expression and protein concentration in mesangial cells cultured in 30 mM glucose medium. MMP-2 mRNA expression was not influenced by C-peptide. In conclusion, C-peptide administration to STZ-diabetic rats for 8 weeks results in the inhibition of diabetes-induced expansion of the mesangial matrix. This effect is independent of the level of glycemic control and results from the inhibition of diabetes-induced excessive formation of mesangial type IV collagen.

Acute postinfectious glomerulonephritis associated with Campylobacter jejuni enteritis - a case report and review of the literature on C. jejuni's potential to trigger immunologically mediated renal disease

Kidney disease is a rare complication of Campylobacter jejuni (C. jejuni) enteritis. We here present the case of an 18-year-old male patient with crampy abdominal pain, vomiting, diarrhea, and fever. Three weeks later urinalysis revealed mild proteinuria and hematuria and a marked raise in serum creatinine was observed. Renal biopsy demonstrated acute endocapillary glomerulonephritis with mesangial IgM (immunoglobuline M) deposits. Extensive workup revealed no signs of skin or joint disease, thus excluding Henoch-Schönlein purpura. Due to persistent abdominal discomfort further gastro-enterological tests were performed and eventually Campylobacter jejuni was isolated from the patient's feces. In the absence of other precipitating factors for renal diseases we presumed an association between the bacterial infection and this postinfectious glomerulonephritis. Over a time period of 6 months the patient's kidney function normalized completely. However, long-term prognosis remains unclear. In addition to the case report, we conducted a review of the literature with results underlining Campylobacter jejuni's potential to trigger various types of immune mediated kidney diseases.

Mesangial pathology in glomerular disease: targets for therapeutic intervention

The glomerulus is the filtration unit of the kidney. Disruption of glomerular function may be caused by primary glomerular pathology or secondary to systemic diseases. The mesangial, endothelial and epithelial cells of the glomerulus are involved in most pathologic processes. Animal models provide an understanding of the molecular basis of glomerular disease. These studies show that mesangial cells are critical players in the initiation and progression of disease. Therefore, modulation of mesangial cell responses offers a novel therapeutic approach. The complex architecture of the kidney, specifically the renal glomerulus, makes targeted drug delivery especially challenging. Targeted delivery of therapeutic agents reduces dose of administration and minimises unwanted side effects caused by toxicity to other tissues. The currently available modalities demonstrating the feasibility of mesangial cell targeting are discussed.

[Clinical baseline and post-nephrectomy characteristics of renal donors with IgA nephropathy diagnosed by time-zero renal biopsy (T0-RBx) compared with donors with normal T0-RBx]

BACKGROUND

The renal manifestations of IgA nephropathy are wide, including patients with asymptomatic disease. The probability of developing advanced renal disease after 20 years of diagnosis varies. The prevalence of mesangial deposits of IgA in otherwise healthy people has been studied previously and there are only 2 reports in which the diagnosis is made by time-zero renal biopsy (TO-RBx).

MATERIAL AND METHODS

We compared clinical characteristics (baseline and at followup) of renal donors with IgA nephropathy diagnosed by TO-RBx compared with 20 donors with normal TO-RBx.

RESULTS

From 1999 to 2006 151 T0-RBx were analyzed. Of these 10 cases (6.62%) had IgA nephropathy. There were two patients with stage II and 8 with stage I according to HASS classification of IgA nephropathy. All donors in both groups (n=30) had normal urinary tests, however urinary protein excretion was significantly higher in the IgA nephropathy group compared with the normal group from baseline to the end of follow-up (three years). The glomerular filtration rate at three years of follow-up was significantly higher in the normal group (80 +/- 14 vs. 65 +/- 8 mL/min, p = 0.001).

CONCLUSIONS

Donors with IgA nephropathy on TO-RBx had no urinary abnormalities during pre donation screening. At three years of follow-up patients with IgA nephropathy showed a greater loss of renal function as well as increased urinary protein excretion.

Transcription factor 7-like 2 (TCF7L2) regulates activin receptor-like kinase 1 (ALK1)/Smad1 pathway for development of diabetic nephropathy

Smad1 has previously been shown to play a key role in the development of diabetic nephropathy (DN), by increasing synthesis of extracellular matrix. However, the regulatory mechanism of Smad1 in DN is still unclear. This study aims to elucidate molecular interactions between activin receptor-like kinase 1 (ALK1)/Smad1 signaling pathway and transcription factor 7-like 2 (TCF7L2) in the progression of DN in vitro and in vivo. The expressions of TCF7L2 and ALK1 were induced by advanced glycation end products (AGEs) in parallel with Smad1, phosphorylated Smad1 (pSmad1), and alpha-smooth muscle actin (α-SMA) through TGF-β1 in cultured mesangial cells. Constitutively active ALK1 increased pSmad1 and α-SMA expressions. The binding of TCF7L2 to ALK1 promoter was confirmed by chromatin immunoprecipitation assay. Furthermore, TCF7L2 induced promoter activity of ALK1. AGEs and TGF-β1 induced a marked increase in TCF7L2 expression in parallel with ALK1. Overexpression of TCF7L2 increased the expressions of ALK1 and Smad1. Inversely, TCF7L2 knockdown by siRNA suppressed α-SMA expression as well as ALK1 and Smad1. The iNOS transgenic mice (iNOS-Tgm), which developed diabetic glomerulosclerosis resembling human diabetic nephropathy, exhibited markedly increased expressions of ALK1, TCF7L2, Smad1, pSmad1, and α-SMA in glomeruli in association with mesangial matrix expansion. These results provide a new evidence that the TCF7L2/ALK1/Smad1 pathway plays a key role in the development of DN.

Deletion of the receptor for advanced glycation end products reduces glomerulosclerosis and preserves renal function in the diabetic OVE26 mouse

OBJECTIVE

Previous studies showed that genetic deletion or pharmacological blockade of the receptor for advanced glycation end products (RAGE) prevents the early structural changes in the glomerulus associated with diabetic nephropathy. To overcome limitations of mouse models that lack the progressive glomerulosclerosis observed in humans, we studied the contribution of RAGE to diabetic nephropathy in the OVE26 type 1 mouse, a model of progressive glomerulosclerosis and decline of renal function.

RESEARCH DESIGN AND METHODS

We bred OVE26 mice with homozygous RAGE knockout (RKO) mice and examined structural changes associated with diabetic nephropathy and used inulin clearance studies and albumin:creatinine measurements to assess renal function. Transcriptional changes in the Tgf-beta1 and plasminogen activator inhibitor 1 gene products were measured to investigate mechanisms underlying accumulation of mesangial matrix in OVE26 mice.

RESULTS

Deletion of RAGE in OVE26 mice reduced nephromegaly, mesangial sclerosis, cast formation, glomerular basement membrane thickening, podocyte effacement, and albuminuria. The significant 29% reduction in glomerular filtration rate observed in OVE26 mice was completely prevented by deletion of RAGE. Increased transcription of the genes for plasminogen activator inhibitor 1, Tgf-beta1, Tgf-beta-induced, and alpha1-(IV) collagen observed in OVE26 renal cortex was significantly reduced in OVE26 RKO kidney cortex. ROCK1 activity was significantly lower in OVE26 RKO compared with OVE26 kidney cortex.

CONCLUSIONS

These data provide compelling evidence for critical roles for RAGE in the pathogenesis of diabetic nephropathy and suggest that strategies targeting RAGE in long-term diabetes may prevent loss of renal function.

Roasted licorice extracts dampen high glucose-induced mesangial hyperplasia and matrix deposition through blocking Akt activation and TGF-beta signaling

Diabetic nephropathy (DN) characterized as nephrotic syndrome and diffuse glomerulosclerosis can cause renal failure and end-stage kidney disease. Expansion of mesangial matrix around capillaries in the kidney glomeruli is a prominent feature of DN. This study investigated whether licorice extracts inhibited mesangial cell (MC) proliferation and matrix accumulation induced by high glucose (HG). Human renal MC were cultured in media containing 5.5 mM glucose plus 27.5 mM mannitol as an osmotic control or 33 mM glucose for 3 d in the presence of water or ethanol extracts from raw licorice (LW, LE) or roasted licorice (RLW, RLE). Non-polar components including glycyrrhetic acid were elevated during licorice roasting, whereas polar components soluble in water extracts were diminished. Exposure of cells to HG caused significant increases in collagen IV secretion and connective tissue growth factor (CTGF) expression, which was appeased by RLW and RLE at transcriptional levels. The inhibitory potency was high in the order of RLE > or = RLW > or = LE > > LW. Non-polar glycyrrhetic acid but not glycyrrhizin retarded HG-stimulated mesangial matrix deposition through diminishing CTGF expression. In addition, RLW and RLE but not LW modulated membrane type matrix metalloproteinase-1 (MT-1 MMP) expression, MMP-2 activity and tissue inhibitor of MMP-2 (TIMP-2), which facilitated the degradation of mesangial matrix. Furthermore, the augmented expression of CTGF and TIMP-2 in HG-exposed cells was mediated by Akt activation and TGF-beta/Smad signaling through PKCbeta2-responsive signaling pathways. However, HG-down-regulated MT-1 MMP expression was independent of activation of ERK1/2 and Akt when using their inhibitors of DB98059 (ERK1/2) and LY294002 (Akt) alone or in combination. These results demonstrate that extracts from roasted licorice may be highly potent therapeutic agents for the prevention and treatment of mesangial fibrosis and glomerulosclerosis leading to diabetes nephropathy due to longstanding diabetes mellitus.

C1q nephropathy in a child presenting with recurrent gross hematuria

C1q nephropathy is a rare glomerular disease characterized by mesangial immune deposits with dominant or codominant staining for C1q. The exact pathogenesis leading to the mesangial immune deposits of C1q remains unknown. C1q nephropathy often presents with proteinuria in the nephrotic range, with an unpredictable or poor response to corticosteroid therapy. It is seen more commonly in older children and young adults and is more common in African Americans compared with Caucasians. We present a 4-year-old African American girl who presented with recurrent gross hematuria in the absence of proteinuria or hypertension and whose renal biopsy demonstrated dominant mesangial deposits of C1q. We conclude that C1q nephropathy should be considered in patients who present with recurrent gross hematuria.