Diosgenin protects against cationic bovine serum albumin-induced membranous glomerulonephritis by attenuating oxidative stress and renal inflammation via the NF-κB pathway.

CONTEXT: Membranous glomerulonephritis (MGN) is a leading cause of nephrotic syndrome in adults. Diosgenin (DG) has been reported to exert antioxidative and anti-inflammatory effects. OBJECTIVE: To investigate the renoprotective activity of DG in a cationic bovine serum albumin-induced rat model of MGN. MATERIALS AND METHODS: Fourty male Sprague-Dawley rats were randomized into four groups. The MGN model was established and treated with a DG dose (10 mg/kg) and a positive control (TPCA1, 10 mg/kg), while normal control and MGN groups received distilled water by gavage for four consecutive weeks. At the end of the experiment, 24 h urinary protein, biochemical indices, oxidation and antioxidant levels, inflammatory parameters, histopathological examination, immunohistochemistry and immunoblotting were evaluated. RESULTS: DG significantly ameliorated kidney dysfunction by decreasing urinary protein (0.56-fold), serum creatinine (SCr) (0.78-fold), BUN (0.71-fold), TC (0.66-fold) and TG (0.73-fold) levels, and increasing ALB (1.44-fold). DG also reduced MDA (0.82-fold) and NO (0.83-fold) levels while increasing the activity of SOD (1.56-fold), CAT (1.25-fold), glutathione peroxidase (GPx) (1.55-fold) and GSH (1.81-fold). Furthermore, DG reduced Keap1 (0.76-fold) expression, Nrf2 nuclear translocation (0.79-fold), and induced NQO1 (1.25-fold) and HO-1 (1.46-fold) expression. Additionally, DG decreased IL-2 (0.55-fold), TNF-α (0.80-fold) and IL-6 (0.75-fold) levels, and reduced protein expression of NF-κB p65 (0.80-fold), IKKß (0.93-fold), p-IKKß (0.89-fold), ICAM-1 (0.88-fold), VCAM-1 (0.91-fold), MCP-1 (0.88-fold) and E-selectin (0.87-fold), and also inhibited the nuclear translocation of NF-κB p65 (0.64-fold). DISCUSSION AND CONCLUSIONS: The results suggest a potential therapeutic benefit of DG against MGN due to the inhibition of the NF-κB pathway, supporting the need for further clinical trials.

Acidic Stigma maydis polysaccharides protect against podocyte injury in membranous nephropathy by maintenance of glomerular filtration barrier integrity and gut-kidney axis.

Membranous nephropathy (MN) is a chronic kidney disease and a precursor to end-stage kidney disease. In this study, we evaluated the potential protective effects of acidic and neutral Stigma maydis polysaccharides (ASMP and NSMP, respectively) on cationized bovine serum albumin-induced MN in mice. Both polysaccharides (SMPs) provided effective protection from kidney injury by decreasing daily proteinuria, kidney dysfunction, and hyperlipidemia and minimizing structural changes and immune complex expression. Furthermore, SMPs improved intestinal barrier damage by increasing the expression of tight junction proteins in the intestinal tissue. They also maintained the integrity of the glomerular filtration barrier by promoting slit diaphragm proteins expression and PI3K/AKT signaling. However, ASMP offered better protection against podocyte injury than NSMP. The use of natural polysaccharides could thus be a new protective measure against podocyte injury and perhaps be utilized for the development of functional foods to protect against MN.

Ameliorated membranous nephropathy activities of two ethanol extracts from corn silk and identification of flavonoid active compounds by LC-MS2.

The current study looks to evaluate the effect of corn silk flavonoids on membranous nephropathy (MN). Polyamide resin (PR) can be used to enrich corn silk ethanol extract (CSEE) to obtain flavonoid-rich extract (PR-CSEE), the total flavonoid content (TFC) of which we found to be 57.4%. The results of scanning electron microscope, Fourier-transform infrared, and high-performance liquid chromatography analyses determined that PR-CSEE and CSEE have different structural characteristics, but that PR-CSEE has higher TFC. MN mice models were induced by cationic bovine serum albumin, and we found that PR-CSEE administration reduced urine protein levels markedly, while renal function, glomerular atrophy, inflammatory infiltration, and in-serum immunoglobulin G and complement 3 content were improved. Through LC-MS2 spectrometry analysis, we pinpointed the 12 major flavonoid active compounds in PR-CSEE. These findings suggest that PR-CSEE can act as a potential functional food material by which to improve MN.

Renoprotective Effects Of Isoliquiritin Against Cationic Bovine Serum Albumin-Induced Membranous Glomerulonephritis In Experimental Rat Model Through Its Anti-Oxidative And Anti-Inflammatory Properties.

BACKGROUND: Membranous glomerulonephritis (MGN) is a nephrotic syndrome which shows the symptoms of heavy proteinuria and immune complex deposition in glomerular sub-epithelial space and finally leads to chronic kidney disease. Isoliquiritin (ILQ) is a flavonoid with a wide range of pharmacological properties, including antioxidant and anti-inflammatory activity. The present study was undertaken to investigate the possible mechanisms by which ILQ ameliorates cationic bovine serum albumin (C-BSA) induced MGN in rat model. METHODS: The MGN condition was confirmed by the 24 hr proteinuria and ILQ (10 mg/kg/bw/day) or TPCA-1 (10 mg/kg/bw/day; IKKß inhibitor) was administered to successfully induce rats for 4 weeks. RESULTS: The present study revealed that MGN rats treated with ILQ showed significantly ameliorated kidney dysfunction and histopathological changes in kidneys. ILQ treated MGN rats alleviated the oxidative stress and were presented with increased anti-oxidative status in kidneys. Furthermore, ILQ treatment to MGN rats showed anti-oxidative effects through the prominent stimulation of Nrf2 signaling pathway and inhibition of Keap1, which consequently increases the Nrf2 nuclear translocation and thereby induces expression of NQO1 and HO-1. In addition, ILQ-treated MGN rats demonstrated anti-inflammatory effects by inhibiting NF-κB signaling pathway through decreased mRNA and protein expressions of NF-κB p65, IKKß, COX-2, iNOS, p38-MAPK, p-p38-MAPK, TNF-α, IL-1ß, IL-8, ICAM-1, E-selectin and VCAM-1 and reduced the nuclear translocation of NF-κB p65. CONCLUSION: The protective effect of ILQ on MGN can be explained by its anti-oxidative and anti-inflammatory activities, which in turn due to the activation of Nrf2 and downregulation of NF-κB pathway.

N-Acetylglucosamine is the most effective glucosamine derivative for the treatment of membranous nephropathy in rats.

Nephroprotective drug development for optimizing treatment of chronic kidney disease (CKD) is an important task of pharmaceutical science. Our study evaluated nephroprotective properties of the two glucosamine derivatives N-acetylglucosamine and glucosamine hydrochloride in a 3-week-long parenteral and oral daily administration at doses of 50 mg/kg in rats with doxorubicin nephropathy. Nephroprotective activity (NA) was evaluated by determining the functional state of the kidneys, the level of azotemia and the activity of free-radical processes in the renal tissue. The results show a significant increase in renal excretory function, normalization of nitrogen metabolism and a decline of free-radical processes under the influence of both studied amino sugars in rats with doxorubicin nephropathy. I. m. route of administration yielded the highest efficacy for both amino sugars with the highest level of NA (83.3%) shown by N-acetylglucosamine. Thus N-acetylglucosamine in i. m. injections has the highest NA among the glucosamine derivatives, and is a promising agent for CKD treatment.

Immunological Pathogenesis of Membranous Nephropathy: Focus on PLA2R1 and Its Role.

Membranous nephropathy (MN) is the major cause of nephrotic syndrome with special pathological features, caused by the formation of immune complexes in the space between podocytes and the glomerular basement membrane. In idiopathic membranous nephropathy (IMN) the immune complexes are formed by circulating antibodies binding mainly to one of two naturally-expressed podocyte antigens: the M-type receptor for secretory phospholipase A2 (PLA2R1) and the Thrombospondin type-1 domain-containing 7A (THSD7A). Formation of antibodies against PLA2R1 is much more common, accounting for 70-80% of IMN. However, the mechanism of anti-podocyte antibody production in IMN is still unclear. In this review, we emphasize that the exposure of PLA2R1 is critical for triggering the pathogenesis of PLA2R1-associated MN, and propose the potential association between inflammation, pollution and PLA2R1. Our review aims to clarify the current research of these precipitating factors in a way that may suggest future directions for discovering the pathogenesis of MN, leading to additional therapeutic targets and strategies for the prevention and early treatment of MN.

Obesidad y riñón / Obesity and the kidney

RESUMEN Introducción: La obesidad es un problema de salud mundial y su frecuencia se está incrementando tanto en adultos como en niños. Una de sus complicaciones es la glomerulopatía asociada a la obesidad. Objetivo: Informar acerca de esta enfermedad y la actitud del pediatra para tratar de evitarla. Métodos: Revisión de la literatura médica más reciente sobre la enfermedad y el incremento de la obesidad en la edad pediátrica en las bases de datos PubMed, SciELO y LILACS. Se utilizaron las palabras clave: glomerulopatía relacionada con la obesidad, obesidad y sobrepeso en el niño, tratamiento de la obesidad. Resultados: La obesidad en el niño es en alto porcentaje de causa nutricional y en esta condición los factores ambientales y socioculturales juegan importante papel. La predisposición a padecer la glomerulopatía de la obesidad comienza desde la niñez. El tratamiento de los pediatras en estos casos estará dirigido a la prevención de la enfermedad puesto que se puede desarrollar en la adultez. Cuando fracasan las medidas preventivas, queda la posibilidad de la cirugía bariátrica con poca experiencia en la edad pediátrica y retos éticos importantes y a pesar de que pudiera ser una alternativa de tratamiento, no es aceptada hasta el presente en forma amplia. Conclusiones: La glomerulopatía de la obesidad, por lo general, no aparece hasta la adultez, pero es necesario prevenirla desde la edad pediátrica y para su prevención los pediatras deben estar atentos a los factores de riesgo que pueden aparecer desde las primeras etapas de la vida(AU)

ABSTRACT Introduction: Obesity is a global health problem and its frequency is increasing as much as in adults than in children. One of its complications is glomerulopathy associated to obesity. Objective: To inform on this disease and the attitude of pediatricians towards this trying to avoid it. Methods: Reviewing of the most recent medical literature on this disease and the increase of obesity in the pediatric age in PubMed, SCIELO and LILACS databases. The keywords used for the search were: glomerulopathy related to obesity, obesity and overweight in children, and obesity treatment. Results: Obesity in children is in a high percentage due to nutritional causes and in this disease environmental and sociocultural factors play an important role. The predisposition to suffer from glomerulopathy by obesity starts in childhood. The treatment prepared by the pediatricians in these cases will be directed to the prevention of the disease because it can be developed in adulthood. When preventive measures fail, there is the possibility of performing a bariatric surgery, having in this regard few experiences in the pediatric ages and important ethical challenges; and instead of being an alternative treatment, it is not widely accepted. Conclusions: Generally, glomerulopathy of obesity doesn't appear until adulthood, but it is necessary to prevent it since the pediatric age; and for its prevention pediatricians must be attentive to the risk factors that can appear from the earliest stages of life(AU)

MiR-130a-5p prevents angiotensin II-induced podocyte apoptosis by modulating M-type phospholipase A2 receptor.

Podocyte apoptosis is considered as the important element that promotes the development and progress of membranous nephropathy (MN). Unfortunately, the underlying mechanism of podocytes apoptosis in MN remains elusive. We compared the renal expressions of miR-130a-5p and M-type phospholipase A2 receptor (PLA2R) between MN patients (n = 30) and 30 controls by qRT-PCR and western blot, respectively. The podocyte damage model in vitro was established by angiotensin II (Ang II, 100 nmol/L) exposure for 24 h. Interaction between miR-130a-5p and PLA2R was determined using dual-luciferase reporter gene assay. MN mice were induced by intravenous injection of cBSA. In this study, miR-130a-5p expression was significantly decreased both in the renal biopsy specimens from MN patients and podocyte cell line AB8/13 following stimulation of Ang II. Overexpressed miR-130a-5p in AB8/13 cells significantly attenuated the Ang II induced-apoptosis in vitro. In contrast, down-regulated miR-130a-5p induced podocyte apoptosis. PLA2R was identified as the target of miR-130a-5p in AB8/13 cells. And up-regulated or down-regulated PLA2R could obviously attenuate the effect of miR-130a-5p overexpression or knockdown on the apoptosis of AB8/13 cells. Furthermore, it was also observed that overexpressed miR-130a-5p by miR-130a-5p agomir could obviously alleviate renal injury in MN mice. In conclusion, decreased miR-130a-5p was contributed to the pathological mechanism of MN through increasing PLA2R expression, which induced podocyte apoptosis.

Betulinic acid, isolated from the leaves of Syzygium cumini (L.) Skeels, ameliorates the proteinuria in experimental membranous nephropathy through regulating Nrf2/NF-κB pathways.

Membranous nephropathy (MN) is associated with increased oxidative stress and inflammatory markers in the kidney. Betulinic acid (BA) is a potent antioxidant and anti-inflammatory compound isolated from the leaves of Syzygium cumini (L.) Skeels. In the present study, we investigated the effects of BA on experimental MN in rats and explored the mechanisms by which it enhances antioxidant activities and resolves inflammatory condition in experimental MN. Passive Heymann nephritis (PHN) was induced in Sprague-Dawley rats by a single tail vein injection of anti- Fx1A antiserum. The rats were orally administered BA (25 and 50 mg kg -1 d -1) or dexamethasone (DEX; 0.07 mg kg-1, reference compound) for 4 weeks after the induction of PHN. Blood, urine, and kidney tissue were collected for analysis at the end of the study. Treatment of PHN rats with BA or DEX significantly attenuated renal dysfunction, histopathological alterations and reduced immune complex deposition in the kidneys. Furthermore, BA ameliorated mRNA and protein expression of NF-κB, iNOS, TNF-α, Nrf2, HO-1 and NQO1 in the kidney. BA also restored malondialdehyde level and antioxidant enzyme activities in the kidney. In a nutshell, the protective effect of BA can be explained by its anti-inflammatory and anti-oxidant activities, which in turn is due to downregulation of NF-κB pathway and activation of Nrf2. The results indicated that BA can effectively suppress experimental PHN in rats by regulating Nrf2/NF-κB pathways.

Sodium restriction potentiates the renoprotective effects of combined vitamin D receptor activation and angiotensin-converting enzyme inhibition in established proteinuric nephropathy.

BACKGROUND: Renin-angiotensin-aldosterone system (RAAS) blockade provides renoprotective effects in chronic kidney disease (CKD); yet progressive renal function loss remains common. Dietary sodium restriction potentiates the renoprotective effects of RAAS blockade. Vitamin D receptor activator (VDRA) treatment reduces proteinuria, inflammation and fibrosis, but whether these effects depend on sodium intake has not been studied. We hypothesized that the renoprotective effects of VDRA treatment, with or without RAAS blockade, are modulated by sodium intake. METHODS: Six weeks after the induction of adriamycin nephrosis in Wistar rats, i.e. with established proteinuria, animals were treated with the VDRA paricalcitol, lisinopril, the combination, or vehicle; each treatment was given during either a high- (2% NaCl) or a low-sodium (0.05% NaCl) diet for 6 weeks. We assessed proteinuria, blood pressure, renal macrophage accumulation and renal expression of the pre-fibrotic marker alpha-smooth muscle actin (α-SMA) at the end of the treatment. RESULTS: Both paricalcitol and lisinopril individually, as well as in combination, reduced proteinuria and glomerular and interstitial inflammation during a low-sodium diet, but not during a high-sodium diet. All interventions also reduced focal glomerulosclerosis and interstitial expression of α-SMA during the low-sodium diet, while similar trends were observed during the high-sodium diet. The renoprotective effects of paricalcitol were not accompanied by blood pressure reduction. As proteinuria was already abolished by lisinopril during the low-sodium diet, the addition of paricalcitol had no further effect on proteinuria or downstream inflammatory or pre-fibrotic changes. CONCLUSION: The renoprotective effects of the VDRA paricalcitol are blood pressure independent but do depend on dietary sodium status. The combination of RAAS blockade, dietary sodium restriction and VDRA may be a promising intervention to further retard renal function loss in CKD.

Varenicline induced acute interstitial nephritis in the setting of idiopathic membranous glomerulonephritis.

BACKGROUND: Varenicline is a nicotinic receptor partial agonist indicated for the cessation of smoking. It is regarded as having no or minimal renal toxicity. A single case report has linked it to acute interstitial nephritis. CASE PRESENTATION: A 56 year-old female with a long-standing history of idiopathic membranous glomerulonephritis presented on routine follow-up with an unexpected rise in her serum creatinine from a stable baseline of 225 umol/L to 319 umol/L Biopsy revealed acute interstitial nephritis. There were no preceding clinical events other than the initiation of varenicline therapy three months prior. This was discontinued with no improvement in renal function. A ten week course of prednisone was initiated and creatinine levels returned to baseline. Shortly after prednisone therapy was completed, renal function worsened but the patient declined further immunosuppressive therapy. Exposure to varenicline therapy two years prior had also resulted in a reversible decline in kidney function. CONCLUSION: This is only the second case report to document varenicline-induced acute interstitial nephritis. A careful medication history and renal biopsy were essential in identifying the etiology of the acute kidney injury in this patient with a complex renal history.

Daedalic DNA vaccination against self antigens as a treatment for chronic kidney disease.

Chronic kidney disease (CKD) is a major cause of death and morbidity in Australia and worldwide. DNA vaccination has been used for targeting foreign antigens to induce immune responses and prevent autoimmune disease, viral infection and cancer. However, the use of DNA vaccination has been restricted by a limited ability to induce strong immune responses, especially against self-antigens which are limited by mechanisms of self-tolerance. Furthermore, there have been few studies on the potential of DNA vaccination in chronic inflammatory diseases, including CKD. We have established strategies of DNA vaccination targeting specific self-antigens in the immune system including co-stimulatory pathways, T cell receptors and chemokine molecules, which have been effective in protecting against the development of CKD in a variety of animal models. In particular, we find that the efficacy of DNA vaccination is improved by dendritic cell (DC) targeting and can protect against animal models of autoimmune nephritis mimicking human membranous nephropathy. In this review, we summarize several approaches that have been tested to improve the efficacy of DNA vaccination in CKD models, including enhanced DNA vaccine delivery methods, DNA vaccine modifications and new molecular targets for DNA vaccination. Finally, we discuss the specific application of DNA vaccination for preventing and treating CKD.

DNA vaccine encoding CD40 targeted to dendritic cells in situ prevents the development of Heymann nephritis in rats.

The CD40-CD154 costimulatory pathway has been shown to be critical for both T- and B-cell activation in autoimmune disease. Here, we assessed the effects of blocking this pathway using CD40 DNA vaccine enhanced by dendritic cell targeting on the development of active Heymann nephritis, a rat model of human membranous nephropathy. DNA vaccination delivers plasmid DNA encoding the target antigen, either alone or in combination with enhancing elements, to induce both humoral and cellular immune responses. To determine whether CD40 DNA vaccine targeting the encoded CD40 directly to dendritic cells would improve the efficacy of the vaccination against self-protein CD40, we utilized a plasmid encoding a single-chain Fv antibody specific for the dendritic cell-restricted antigen-uptake receptor DEC205 (scDEC), the target gene CD40, and the adjuvant tetanus sequence p30. This vaccine plasmid was compared to a control plasmid without scDEC. Rats vaccinated with scDEC-CD40 had significantly less proteinuria and renal injury than did rats receiving scControl-CD40 and were protected from developing Heymann nephritis. Thus, CD40 DNA vaccination targeted to dendritic cells limits the development of Heymann nephritis.

Universal hepatitis B vaccination reduces childhood hepatitis B virus-associated membranous nephropathy.

OBJECTIVE: To compare the incidence of hepatitis B virus (HBV)-associated membranous nephropathy (HBVMN) before and after universal HBV vaccination and to identify factors underlying the change. METHODS: This study included 471 hospitalized children with nephrotic syndrome (NS) and 488 long-term follow-up hepatitis B surface antigen (HBsAg)-carrier children. Horizontal transmission (negative maternal HBsAg status) of HBVMN and HBV was assessed, and the incidence of HBVMN was compared before and after initiation of the universal HBV vaccination program started in 1984. RESULTS: The frequency of HBVMN in children with NS was 11.6% between 1974 and 1984, 4.5% between 1984 and 1994, 2.1% between 1994 and 2004, and 0% between 2004 and 2009. Similarly, the number of HBsAg-seropositive children with NS (mainly via horizontal infection) decreased after universal vaccination. The prevaccination frequency of HBV horizontal transmission in chronic HBsAg carriers from the general population was 36.5% compared with 5% in the postvaccination period. The incidence of HBVMN in these carriers revealed a parallel decline. CONCLUSIONS: Our results revealed a significant decrease in the frequency of HBVMN in children with NS and in long-term follow-up HBsAg carriers. Children with HBVMN are primarily infected with HBV via horizontal transmission; thus, the significant reduction in horizontal transmission in HBsAg-carrier children in the general population after universal HBV vaccination may explain the reduction of HBVMN in the vaccinated population. These findings confirm the effectiveness of HBV vaccination on reducing the incidence of HBVMN, possibly through a significant decline in horizontal HBV infection.

New vaccination technology for endogenous antigen-derived ailments.

Neither autoimmune disorders nor cancer can be prevented with treatment modalities that are currently available. These diseases are generally treated with immunosuppressive agents and cytotoxic drugs, both of which can cause numerous side effects. However, scientific evidence now exists to suggest that such endogenous antigen-derived ailments can be controlled and even terminated by immunological approaches. Both autoimmune disorders and cancer can progress into chronic, irreversible conditions because of the abnormal presentation of endogenous antigens to the cells of the immune system. By appropriate regulation of the autoimmune system, both types of ailments could be curable. This feature review describes various autoimmune events that may occur both to the benefit and the detriment of the host, and highlights a new vaccination technique against slowly progressive Heymann nephritis. This modified vaccination technique holds promise in the prevention and cure of autoimmune system-related disorders. The vaccination has been employed both against endogenous antigen-induced diseases (autoimmune disorders and cancer) and against exogenous antigens. In each study performed to date, the technique has been demonstrated to induce specific, predetermined immune response outcomes.

Amelioration of anti-Thy1-glomerulonephritis by PPAR-gamma agonism without increase of endothelial progenitor cell homing.

Impaired glomerular endothelial integrity is pivotal in various renal diseases and depends on both the degree of glomerular endothelial injury and the effectiveness of glomerular endothelial repair. Glomerular endothelial repair is, in part, mediated by bone marrow-derived endothelial progenitor cells. Peroxisome proliferator activated receptor-gamma (PPAR-gamma) agonists have therapeutic actions independent of their insulin-sensitizing effects, including enhancement of endothelial progenitor cell function and differentiation. We evaluated the effect of PPAR-gamma agonist rosiglitazone (4 mg.kg(-1).day(-1)) on the course of anti-Thy1-glomerulonephritis in rats. Rosiglitazone limited the development of proteinuria and prevented plasma urea elevation (8.1 +/- 0.4 vs. 12.5 +/- 1.1 mmol/l, P = 0.002). Histologically, inflammatory cell influx was not affected, but rosiglitazone-treated rats did show fewer microaneurysmatic glomeruli on day 7 (26 +/- 3 vs. 41 +/- 5%, P = 0.01) and reduced activation of matrix production with reduced renal cortical transforming growth factor-beta, plasminogen activator inhibitor type 1, and fibronectin-1 mRNA expression. However, bone marrow-derived endothelial cell glomerular incorporation was not enhanced (3.1 +/- 0.4 vs. 3.6 +/- 0.3 cells/glomerular cross section; P = 0.31). Rosiglitazone treatment in nonnephritic rats did not influence proteinuria, urea, or renal histology. In conclusion, treatment with PPAR-gamma agonist rosiglitazone ameliorates the course of experimental glomerulonephritis in a nondiabetic model, but not through enhancing incorporation of bone marrow-derived endothelial cells in the glomerulus.

Effects of rapamycin on active Heymann nephritis.

BACKGROUND/AIM: The effects of rapamycin (RAPA) were examined in active Heymann nephritis (HN), an experimental model of human membranous nephropathy (MN). Current opinion on the therapy of MN is controversial, and medications used for its treatment have not yielded the expected results. METHODS: In a two-part study, we examined the effects of RAPA (1.5 mg/kg/day) during the induction phase of HN and on the evolving disease. In both parts, control groups of immunized rats not treated with RAPA and control groups of unimmunized rats were observed and sacrificed concurrently with the treated groups. RESULTS: During the induction phase no significant changes in proteinuria were observed in the group treated with RAPA, in comparison to those in the untreated group (p < 0.001). During the evolving disease RAPA significantly lowered proteinuria (p < 0.001). The characteristic pathohistologic changes and IgG depositions along the glomerular basement membrane were considerably diminished, and infiltration of CD8+ cells completely prevented. CONCLUSION: RAPA demonstrated beneficial effects on disease progression, given either in the induction phase or during evolving HN. It would be desirable to investigate the effect of RAPA on patients with MN.

C-reactive protein-mediated suppression of nephrotoxic nephritis: role of macrophages, complement, and Fcgamma receptors.

C-reactive protein (CRP) is a member of the pentraxin family of proteins and an acute phase reactant. CRP modulates the response to inflammatory stimuli including LPS and C5a. We recently demonstrated that CRP prevents and reverses proteinuria in accelerated nephrotoxic nephritis (NTN). NTN is a model of active inflammatory immune complex-mediated nephritis induced by injection of antiglomerular basement membrane. CRP treatment prevented the induction of NTN in C57BL/6 (B6) mice, increased survival, and reversed ongoing nephritis. Protection was associated with a decrease in IL-1beta and chemokines in the kidney and peritoneal cells as measured by quantitative RT-PCR. However, IL-10(-/-) mice were not protected by CRP either when given before disease onset or when disease activity was maximal. FcgammaRI(-/-) mice developed NTN, but were only transiently protected by CRP treatment. This transient protection was abrogated by cobra venom factor depletion of complement from FcgammaRI(-/-) mice. However, complement depletion did not prevent CRP-mediated protection in B6 mice, and CRP was protective in C3(-/-) mice. The role of macrophages in the protection provided by CRP was tested by treating B6 mice with liposomes containing clodronate. Clodronate-containing liposomes deplete mice of splenic and hepatic macrophages for 5-7 days. Pretreatment of NTN mice with clodronate but not control liposomes completely prevented CRP-mediated protection. These studies suggest that CRP mediates protection from NTN through the induction of IL-10 and that macrophages are required. In addition, FcgammaRI plays an important role but is not the sole mediator of CRP-mediated protection.

Lamivudine in hepatitis B-associated membranous nephropathy.

BACKGROUND: Although lamivudine is effective for treatment of chronic hepatitis B (HBV) infection, its potential therapeutic impact on HBV-related membranous nephropathy (MN) in adults has not been characterized. METHODS: We treated 10 HBsAg-positive patients with biopsy-proven MN, elevated serum alanine aminotransferase (ALT), and HBV-DNAemia (group 1), and compared their clinical course with 12 patients diagnosed to have HBV infection, elevated serum ALT, and MN in the pre-lamivudine era (group 2). RESULTS: Baseline demographic and clinical parameters were not different between the 2 groups. In group 1, lamivudine treatment was associated with significant reduction in proteinuria, increase in serum albumin, normalization of ALT levels, and disappearance of circulating HBV-DNA during the first year. Four (40%) and 6 (60%) patients went into complete remission (proteinuria <0.3 g/d) at 6 and 12 months, respectively. In group 2, significant proteinuria persisted during the first year. One (8.3%) and 3 (25%) patients went into remission. Cumulative 3-year renal survival [using end-stage renal disease (ESRD) as primary end point] was 100% in group 1 and 58% in group 2 (P= 0.024, log rank test). Blood pressure control reached the target of below 130/85 mm Hg in both groups. Lamivudine was well tolerated and not associated with any adverse events. Hepatic decompensation or malignancy was not observed during follow-up in both groups. CONCLUSION: HBV-related MN leads to ESRD in a significant proportion of patients before the advent of antiviral therapy. Lamivudine treatment improves renal outcome in HBV carriers with MN and evidence of liver disease.