Decreased Excretion of Urinary Exosomal Aquaporin-2 in a Puromycin Aminonucleoside-Induced Nephrotic Syndrome Model

Urinary exosomes, small extracellular vesicles present in urine, are secreted from all types of renal epithelial cells. Aquaporin-2 (AQP2), a vasopressin-regulated water channel protein, is known to be selectively excreted into the urine through exosomes (UE-AQP2), and its renal expression is decreased in nephrotic syndrome. However, it is still unclear whether excretion of UE-AQP2 is altered in nephrotic syndrome. In this study, we examined the excretion of UE-AQP2 in an experimental rat model of nephrotic syndrome induced by the administration of puromycin aminonucleoside (PAN). Rats were assigned to two groups: a control group administered saline and a PAN group given a single intraperitoneal injection of PAN (125 mg/kg) at day 0. The experiment was continued for 8 days, and samples of urine, blood, and tissue were collected on days 2, 5, and 8. The blood and urine parameters revealed that PAN induced nephrotic syndrome on days 5 and 8, and decreases in the excretion of UE-AQP2 were detected on days 2 through 8 in the PAN group. Immunohistochemistry showed that the renal expression of AQP2 was decreased on days 5 and 8. The release of exosomal marker proteins into the urine through UEs was decreased on day 5 and increased on day 8. These data suggest that UE-AQP2 is decreased in PAN-induced nephrotic syndrome and that this reflects its renal expression in the marked proteinuria phase after PAN treatment.

Curcumin, as a pleiotropic agent, improves doxorubicin-induced nephrotic syndrome in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Curcumin, a phenolic compound extracted from the rhizome of turmeric (Curcuma longa L.), has been reported to have broad biological functions including potent antioxidant and renoprotective effects. It has been reported that Curcumin has a certain protective effect on the kidney. However, its mechanism of action needs further study.

AIM OF THE STUDY

The present research aims at investigating the therapeutic effects and its underlying mechanism of curcumin on NS.

MATERIALS AND METHODS

The conditionally immortalized mouse podocyte cell line was utilized to evaluate the podocyte-protective effect of curcumin and its effects on NF-κB pathway and Nrf2/ARE pathway in podocyte in vitro. Furthermore, the DOX-induced NS rats were utilized to investigate the therapeutic effects and its underlying mechanism of curcumin against NS in vivo.

RESULTS

The consequences of this study revealed that curcumin activated Nrf2, inhibited NF-κB pathway and up-regulated podocin in DOX-induced podocyte. Further research results showed that curcumin can considerably alleviate proteinuria and improve hypoalbuminemia in NS rats, and lower blood lipid levels to alleviate hyperlipidemia in NS rats, indicating that curcumin has significant therapeutic effects on rat NS. Further observation by electron microscopy and detection showed that curcumin can improve renal function and podocyte injury, which may be related to the repairment of mRNA expression and podocin protein. Interestingly, the results of the blood rheology test showed that curcumin can effectively reduce whole blood viscosity (WBV) and plasma viscosity (PV), and reduce hematocrit (Hct). In addition, the oxidative stress state of kidney in NS rats was considerably reversed by curcumin, which may be achieved by activating Nrf2 and increasing the expression of antioxidant enzymes HO-1, NQO-1. We also found that NF-κB pathway is activated in the kidney of NS rats, and curcumin can inhibit the activation of NF-κB by down-regulating the expression of NF-κB p65, reducing the level of p-IκBα and up-regulating the expression of IκBα.

CONCLUSION

These findings suggest that curcumin, as a multifunctional agent, exerts a protective effect on DOX-induced nephrotic syndrome in rats, which provides a pharmacological basis for the further development of curcumin and also provides a basis for the advantages of multi-targeted drugs in the processing of NS.

[A Case of Nephrotic Syndrome Induced by FOLFIRI plus Ramucirumab for Metastatic Descending Colon Cancer]

We report a case of multiple lung metastases of RAS mutant type descending colon cancer with development of nephrotic syndrome after the introduction of FOLFIRI plus ramucirumab(RAM). A female patient in her 50s underwent adjuvant chemotherapy with capecitabine and oxaliplatin after primary tumor and partial lung resection. For recurrent multiple lung metastases, 4 years of capecitabine and bevacizumab therapy was administered. FOLFIRI plus RAM therapy was introduced because of tumor progression. After treatment, the patient showed increased urine protein content, decreased serum albumin levels, marked hypertension, and increased edema, and was diagnosed with nephrotic syndrome. The patient's condition improved with prednisolone, additional doses of antihypertensive, and diuretics. Even in cases where it is possible to control proteinuria during bevacizumab administration, it is necessary to keep in mind that RAM administration as second-line therapy may cause nephrotic syndrome.

Bevacizumab-induced immunoglobulin A vasculitis with nephritis: A case report

RATIONALE

Bevacizumab-an inhibitor of vascular endothelial growth factor-is effective against various advanced cancers. However, it is associated with the development of hypertension and high-grade proteinuria during thrombotic microangiopathy of the kidney. In addition, there are several reports of immunoglobulin A deposition in the glomeruli, but the etiology is unclear.

PATIENT CONCERNS

A 67-year-old Japanese man with metastatic rectal cancer underwent low anterior rectal resection, followed by treatment with bevacizumab and SOX (S-1 plus oxaliplatin). Six months later, the patient developed hematuria, nephrotic syndrome, and purpura.

DIAGNOSES

Renal biopsy revealed endocapillary proliferative glomerulonephritis. Immunofluorescence analyses showed granular mesangial deposition of galactose-deficient immunoglobulin A1. Skin biopsy revealed leukocytoclastic vasculitis.

INTERVENTIONS

We ceased bevacizumab treatment, while continuing the remaining chemotherapy regimen, as we suspected bevacizumab-induced nephropathy.

OUTCOMES

Proteinuria and purpura improved immediately after cessation of bevacizumab. We identified this as a case of bevacizumab-induced immunoglobulin A vasculitis with nephritis.

LESSONS

To our knowledge, this is the first case of bevacizumab-related immunoglobulin A vasculitis with nephritis, as evidenced by galactose-deficient immunoglobulin A1. When a patient's urine tests are abnormal during bevacizumab treatment, clinicians should consider not only thrombotic microangiopathy but also vasculitis.

Sertraline Reduces Albuminuria by Interfering with Caveolae-Mediated Endocytosis through Glomerular Endothelial and Epithelial Cells

INTRODUCTION

Previously, we reported the caveolae-mediated intracellular trafficking pathway of albumin through glomerular endothelial cells (GEnCs) as a new etiological hypothesis of urinary albumin excretion. The selective serotonin reuptake inhibitor, sertraline (Ser), inhibits dynamin, which plays a pivotal role in the fission of caveolae from the cell membrane during caveolae endocytosis.

OBJECTIVE

In this study, we evaluated whether Ser reduces albuminuria levels by interfering with albumin endocytosis through caveolae into GEnCs and podocytes as a novel treatment for glomerulonephritis.

METHODS

After treating the cells with Ser, albumin and caveolin-1 (Cav-1) expression levels were evaluated by immunofluorescence (IF) and western blot (WB) analyses. The albuminuria level was determined by histology in a puromycin aminonucleoside (PAN)-induced nephrotic syndrome mouse model (PAN mice) treated with or without Ser.

RESULTS

IF and WB analyses showed that the albumin expression level was significantly decreased by Ser treatment; however, Cav-1 expression was not decreased in GEnCs or podocytes based on the IF results. In PAN mice treated with or without Ser, Cav-1 expression increased, and the foot process effacement of podocytes and swelling of GEnCs were observed. However, proteinuria levels were not increased in PAN mice treated with Ser relative to that in normal control mice (p = 0.17), and a significant increase was observed in PAN mice without Ser treatment (p = 0.0027).

CONCLUSIONS

Ser interfered with albumin internalization through the caveolae into GEnCs and podocytes and reduced albuminuria. Dynamin inhibitors may serve as a novel therapeutic option for reducing albuminuria in glomerulonephritis.

[Minimal change disease during lithium therapy: case report]

Lithium is a largely used and effective therapy in the treatment of bipolar disorder. Its toxic effects on kidneys are mostly diabetes insipidus, hyperchloremic metabolic acidosis and tubulointerstitial nephritis. Also, a correlation between lithium and minimal change disease has sometimes been described. We report here the case of a patient with severe bipolar disorder on lithium therapy who, without any pre-existing nephropathy, developed nephrotic syndrome and AKI with histopathologic findings pointing to minimal change disease. The patient was treated with symptomatic therapy; the discontinuation of lithium therapy resulted in the remission of AKI and of the nephrotic syndrome, thus suggesting a close relationship between lithium and minimal change disease.

Nephrotic syndrome following four-component meningococcal B vaccination: Epidemiologic investigation of a surveillance signal

BACKGROUND

In May 2014, a mass vaccination campaign with four-component meningococcal serogroup B (4CMenB) vaccine was launched in a localized region of Quebec, Canada experiencing high invasive meningococcal B disease endemicity. Active post-marketing surveillance identified several cases of nephrotic syndrome (NS) among ∼49,000 vaccinated individuals aged 2 months to 20 years. We report the epidemiologic investigation of this potential vaccine safety signal.

METHODS

Active vaccine safety surveillance was conducted electronically, with participants completing an online questionnaire prompted at 7 days after each dose and 6 months following the last dose. Additional NS cases were sought from provincial hospitalization and emergency room databases.

RESULTS

In the year following the first dose of 4CMenB vaccination, four confirmed NS cases (three hospitalized) were identified among vaccinated children 2-5-years-old with onset several months post-vaccination. None had renal biopsy but given their age, and positive response to steroids, idiopathic NS was presumptively diagnosed. Among vaccinated children 1-9-years-old, the NS incidence in the year post-vaccination was 17.7 per 100,000 (1 per 5650 vaccinees) with an NS hospitalization rate (i.e. excluding the outpatient case) that was 3.6-fold higher (95%CI = 0.7-11.8; p = 0.12) than the rest of the province for the same period, and 8.3-fold greater (95%CI = 1.1-62.0; p = 0.039) than during the eight years preceding the immunization campaign in the affected region.

CONCLUSION

Active safety surveillance identified an unexpected increase in NS incidence following 4CMenB vaccination. Further epidemiological investigation identified four vaccinated cases in total over a 12 month period of follow up. The greater risk in vaccinees had wide confidence intervals with he lower limit including or just above the nul value, an observation with no or marginal statistical significance. The temporal association with vaccination may be explained by other causes and/or chance clustering of a rare event unrelated to vaccination. To confirm or refute a potential link to vaccination, surveillance in other jurisdictions administering 4CMenB to children 1-9-years-old is needed.

Nephrotic syndrome associated with ramucirumab therapy: A single-center case series and literature review

Ramucirumab is a human immunoglobulin G1 monoclonal antibody that binds to vascular endothelial growth factor receptor 2 and is used for the treatment of metastatic or inoperable gastric, colorectal, and non-small cell lung cancers. However, ramucirumab can result in renal adverse events, including nephrotic syndrome, and the clinical course of this event is unclear. This study aimed to investigate the clinical course and pathological findings of patients with nephrotic syndrome after ramucirumab treatment.We evaluated 5 patients with malignancies (2 cases of gastric cancer and 3 cases of colorectal cancer) who developed nephrotic syndrome during treatment with ramucirumab. Two patients were diagnosed based on renal biopsy. We investigated the relationship between ramucirumab treatment and clinical courses, pathological findings, and renal outcomes.Four of 5 patients developed nephrotic syndrome after 1 or 2 doses of ramucirumab. All patients had hypertension, and 2 of 5 patients had renal dysfunction, defined as an increase in serum creatinine levels of ≥50% or ≥0.3 mg/dL. The 2 renal biopsy samples revealed a diffuse glomerular basement membrane double contour, intracapillary foam cell infiltration, and partial foot process effacement. Early drug discontinuation and antihypertensive therapy improved proteinuria, renal dysfunction, and hypertension in all patients.Nephrotic syndrome is a renal adverse event observed in cancer patients after ramucirumab treatment. We suggest that urinalysis, renal function, and blood pressure should be closely monitored in patients undergoing ramucirumab treatment, and treatment should be discontinued if renal adverse events are detected.

A Novel Hybrid Cytokine IL233 Mediates regeneration following Doxorubicin-Induced Nephrotoxic Injury

Kidney injury, whether due to ischemic insults or chemotherapeutic agents, is exacerbated by inflammation, whereas Tregs are protective. We recently showed that IL-2 and IL-33, especially as a hybrid cytokine (IL233 - bearing IL-2 and IL-33 activities in one molecule), potentiated Tregs and group 2 innate lymphoid cells (ILC2) to prevent renal injury. Recent studies have indicated a reparative function for Tregs and ILC2. Here, using doxorubicin-induced nephrotoxic renal injury model, we investigated whether IL233 administration either before, late or very late after renal injury can restore kidney structure and function. We found that IL233 treatment even 2-weeks post-doxorubicin completely restored kidney function accompanied with an increase Treg and ILC2 in lymphoid and renal compartments, augmented anti-inflammatory cytokines and attenuated proinflammatory cytokine levels. IL233 treated mice had reduced inflammation, kidney injury (Score values - saline: 3.34 ± 0.334; IL233 pre: 0.42 ± 0.162; IL233 24 hrs: 1.34 ± 0.43; IL233 1 week: 1.2 ± 0.41; IL233 2 week: 0.47 ± 0.37; IL233 24 hrs + PC61: 3.5 ± 0.74) and fibrosis in all treatment regimen as compared to saline controls. Importantly, mice treated with IL233 displayed a reparative program in the kidneys, as evidenced by increased expression of genes for renal progenitor-cells and nephron segments. Our findings present the first evidence of an immunoregulatory cytokine, IL233, which could be a potent therapeutic strategy that augments Treg and ILC2 to not only inhibit renal injury, but also promote regeneration.

[A Case of Nephrotic Syndrome Due to SOX plus Bmab Therapy for Liver Metastasis of Rectal Cancer]

A 66-year-old man was postoperatively diagnosed with pT4a, pN2, cM1a(H2), cP0, fStage Ⅳ, RAS wild type rectal cancer. He underwent SOX plus Bmab chemotherapy 4 weeks later. After 9 courses of SOX plus Bmab, he was admitted to the hospital for leg edema and proteinuria(4+). Because of severe proteinuria(14.7 g/day)and low protein(Alb 2.0 g/dL, TP 4.9 g/dL), he was diagnosed with nephrotic syndrome. His general condition improved on stopping chemotherapy and administration of conservative treatment, and he was discharged on day 20 after admission. The proteinuria improved 3 months later. He had been undergoing SOX chemotherapy for 4 months.

Renal-limited thrombotic microangiopathy after switching from bevacizumab to ramucirumab: a case report

BACKGROUND

It is well known that vascular endothelial growth factor (VEGF) inhibitors can cause proteinuria. The incidence of proteinuria is high for bevacizumab, a humanized monoclonal antibody directed against VEGF, but the range of proteinuria rarely becomes nephrotic (2.2% occurrence according to a meta-analysis). In such cases, renal pathology shows thrombotic microangiopathy (TMA). Ramucirumab, anti-VEGF receptor 2 (VEGFR2) monoclonal antibody, can also cause proteinuria, but it is not yet reported whether the drug may induce TMA.

CASE PRESENTATION

Here, we report a case who immediately developed TMA by ramucirumab after multiple courses of bevacizumab treatment. This is the first case of pathologically-proved TMA by ramucirumab. After cessation of the drug, symptoms of TMA improved gradually.

CONCLUSIONS

This case demonstrates that not only blockade of VEGF but also VEGFR2 antagonism may result in TMA, which is a rare but life-threatening complication of cancer treatment drug.

[Nephrotic Syndrome Induced by Ramucirumab for Metastatic Rectal Cancer]

We report a case of nephrotic syndrome induced by ramucirumab for metastatic rectal cancer. A 48-year old woman who had received FOLFIRI plus ramucirumab for rectal cancer with liver, lung, and bone metastases presented to our hospital with edema and increased body weight. Laboratory studies showed hypoalbuminemia and severe proteinuria, and the patient was diagnosed with nephrotic syndrome. After administration of an angiotensin II receptor blocker and thiazide diuretic, her symptoms disappeared and serum albumin level normalized. To the best of our knowledge, this is the first detailed report of nephrotic syndrome related to ramucirumab. This case serves to emphasize that the possibility of nephrotic syndrome should be considered during anti-vascular endothelial growth factor therapy.

Minimal change disease related to rifampicin presenting with acute renal failure during treatment for latent tuberculosis infection: A case report

RATIONALE

The standard drugs used to treat tuberculosis are rifampicin and isoniazid. These agents are usually safe and inexpensive for short-term use in treatment of latent tuberculosis infection, but sometimes cause adverse renal effects, including minimal change disease (MCD).

PATIENT CONCERNS

Here, we report a 51-year-old woman with latent tuberculosis infection who developed nephrotic syndrome during treatment with rifampicin and isoniazid for 25 days.

DIAGNOSES

Renal biopsy findings were compatible with MCD, and she had no relevant medical history and was not taking other medications. A diagnosis of anti-tuberculosis drug- induced MCD was made. This is the first report of acute renal failure due to rifampicin and/or isoniazid-induced MCD.

INTERVENTIONS

After cessation of rifampicin and isoniazid, however, acute renal failure progressed and she was treated with temporary dialysis and oral prednisolone.

OUTCOMES

The patient achieved complete remission after cessation of rifampicin and isoniazid with steroid therapy.

LESSONS

This case demonstrates that rifampicin and/or isoniazid can cause nephrotic syndrome with acute renal failure during the first months of continuous latent tuberculosis therapy. Therefore, renal function and proteinuria should be monitored carefully in all patients taking rifampicin and isoniazid, especially during the first few months of therapy.

Pazopanib-induced Endothelial Injury with Podocyte Changes

Pazopanib has been reported to induce proteinuria; however, no pathological findings have been reported. We herein report the case of a 31-year-old man with rhabdomyosarcoma treated with pazopanib who developed nephrotic syndrome. A renal biopsy revealed endothelial injury with podocyte changes. Based on the biopsy findings, we diagnosed the patient with nephrotic syndrome caused by pazopanib. Following the discontinuation of pazopanib, the patient's proteinuria gradually decreased without any specific treatment. We should be careful when encountering drug-induced proteinuria in patients taking pazopanib.

The Detection of Urinary Podocytes from Drug-Induced Glomerular Thrombotic Microangiopathy in Advanced Cancer Patients

BACKGROUND

Focusing on glomerular thrombotic microangiopathy (TMA), we detected urinary podocytes to evaluate podocyte damage following glomerular endothelial cell injury.

METHODS

We analyzed the relationship between urinary podocytes as biomarkers for podocyte injuries and clinical manifestations in five patients of anti-cancer-drug-induced glomerular TMA.

RESULTS

Cancer in all five patients was advanced, including 4 cases of renal cell carcinoma treated with tyrosine kinase inhibitor, and one with intrahepatic bile duct carcinoma treated with gemcitabine. Urinary podocytes were detected in 2 cases that rapidly developed acute kidney injury (AKI) and nephrotic syndrome, while they were not detected in 3 cases of slowly progressive chronic renal failure. One case with AKI, presenting sequential manifestations of urinary podocytes, showed the decrease and disappearance of urinary podocytes in accordance with the cessation of the anti-cancer drug, followed by improvement in renal function and in clinical symptoms such as hypertension.

CONCLUSIONS

These findings indicate that severe endothelial cell dysfunction during the acute phase of glomerular TMA leads to podocyte loss.

Nephrotic syndrome under treatment with dasatinib: be aware of a possible adverse drug reaction

The protein kinase inhibitor dasatinib, targeting BCR-ABL and Src family kinases, is used in chronic myeloid leukaemia and Philadelphia-chromosome positive acute lymphoblastic leukaemia. The Netherlands Pharmacovigilance Centre Lareb has received one report of nephrotic syndrome associated with the use of dasatinib. With some other protein kinase inhibitors, targeting vascular endothelial growth factor, nephrotic syndrome is a well-known adverse drug reaction. The Dutch and European pharmacovigilance databases and scientific literature contain several cases indicating a causal relationship between dasatinib and nephrotic syndrome. Nephrotic syndrome was recently added to the list of adverse drug reactions in the Dutch summary of product characteristics for dasatinib. It is important to recognise the possibility of this adverse drug reaction when a patient develops nephrotic syndrome under treatment with dasatinib.

Plantago asiatica L. Ameliorates Puromycin Aminonucleoside-Induced Nephrotic Syndrome by Suppressing Inflammation and Apoptosis

Objective: Nephrotic syndrome, a kidney disease with a variety of causes, is mainly characterized by heavy proteinuria, hypoproteinemia, and ascites. This study was designed to evaluate the underlying mechanism of action of Plantago asiatica L. (PAL) in treating nephrotic syndrome induced by puromycin aminonucleoside. Methods: PAL has been used in Asia as a traditional medicine and dietary health supplement. Sprague-Dawley (SD) rats were intravenously injected with puromycin aminonucleoside (75 mg/kg/day), then treated with either Losartan (30 mg/kg/day) or PAL (200 mg/kg/day) by oral gavage for seven days. Results: PAL significantly decreased ascites, proteinuria level, and plasma lipid parameters. In addition, treatment with PAL attenuated histological damage and hypoalbuminemia. Treatment with PAL also restored podocin expression and reduced inflammation markers such as intracellular adhesion molecules (ICAM-1), monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor alpha (TNF-α) and high-mobility group box-1 (HMGB1). Lower expression levels of the apoptosis markers Bax, caspase-3 and capase-9 were documented in SD rats receiving PAL. PAL also significantly decreased the phosphorylation levels of MAPKs such as ERK, JNK and p38. Conclusion: As a multifunctional agent, PAL has a renoprotective effect in nephrotic syndrome rat models. The anti-inflammatory and anti-apoptotic properties, along with reductions in hyperlipidemia and ascites, represent important therapeutic effects. These results indicate that Plantago asiatica is likely to be a promising agent in the treatment of nephrotic syndrome.

NAC attenuates adriamycin-induced nephrotic syndrome in rats through regulating TLR4 signaling pathway

OBJECTIVE

Nephrotic syndrome (NS) is a detrimental renal disease that affects a large population. It is suggested that Toll-like Receptor 4 (TLR4) signaling pathway plays an important role in NS. The aim of this study was to evaluate the immunosuppressive effect of N-acetylcysteine (NAC) in the treatment of NS elucidate its interaction with TLR4 pathway in a rat model.

MATERIALS AND METHODS

Rat NS model was constructed using the Bertain method by injecting adriamycin (4.5 mg/kg) intravenously at day 1, and injecting 2 mg/kg adriamycin (ADR) at day 7. NS rats were treatment with NAC of 150 mg/kg daily through gavage. Control rats received equivalent amounts of saline daily. Quantitative Real-time PCR was used to evaluate TLR4 expression in kidney tissues after treatments. Western blot analysis was used to evaluate NF-κBp65 expression. ELISA was used to evaluate the expression of immunological factors, including TNF-α, IL-6, and IL-1β.

RESULTS

Rat NS models demonstrated higher protein levels in urine, accompanied by an increased in the TLR4 level. After NAC treatment, TLR4 level was reduced. NAC treatment also attenuated the NF-κBp65 overexpression in NS rats. Concomitantly, TNF-α, IL-6, and IL-1β levels, which are indicators of immunological and informatory responses, were also decreased after NAC treatment.

CONCLUSIONS

NAC treatment ameliorated nephrotic syndrome in NS rat models by suppressing TLR4 signaling, as well as immunological and inflammatory responses.

Histopathological Changes in Arsenic Kushta Induced Nephrotoxicity in Wistar Rats

OBJECTIVE

To determine the nephrotoxic effects of arsenic kushta (Kushta Sam-ul-Far) in Wistar rats.

STUDY DESIGN

Experimental study.

PLACE AND DURATION OF STUDY

Department of Morbid Anatomy and Histopathology, University of Health Sciences, Lahore from May to August 2014.

METHODOLOGY

This experimental study was conducted on 48 healthy Wistar rats, each weighing 200 - 250 grams. The rats were randomly divided into 4 experimental groups each containing 12 rats. Group I was taken as control given flour pellets. Group II was given single dose (180 mg/kg) of arsenic kushta for 2 weeks. Group III received 150 mg/kg of arsenic kushta for 12 weeks; whereas, group IV was also given 150 mg/kg of arsenic kushta for 12 weeks along with 75 mg of BSA (bovine serum albumin). Histopathological changes in glomeruli, tubules and interstitium were noted in the kidney.

RESULTS

Mesangial proliferation, thickening of basement membrane, necrosis, and interstitial edema were mainly observed in all the above groups except group I which served as control. These changes were seen in greater severity in high dose groups and the group given BSA injection along with kushta (group III, IV).

CONCLUSION

Herbo-mineral preparations of arsenic kushta are nephrotoxic in rats and may have similar toxic effects in human beings.

Effect of clofibrate on fatty acid metabolism in the kidney of puromycin-induced nephrotic rats

BACKGROUND

Proteinuria plays an essential role in the progression of tubulointerstitial damage, which causes end-stage renal disease. An increased load of fatty acids bound to albumin reabsorbed into proximal tubular epithelial cells (PTECs) contributes to tubulointerstitial damage. Fibrates, agonists of peroxisome proliferator-activated receptor α (PPARα), have renoprotective effects against proteinuria whereas the effects of these compounds on fatty acid metabolism in the kidney are still unknown. Therefore, the present study examined whether the renoprotective effects of clofibrate were associated with improvement of fatty acid metabolism in puromycin aminonucleoside (PAN)-induced nephrotic rats.

METHODS

Rats were allocated to the control, PAN or clofibrate-treated PAN group. Biochemical parameters, renal injury and changes in fatty acid metabolism were studied on day14.

RESULTS

PAN increased proteinuria, lipid accumulation in PTECs, excretions of N-acetyl-β-D-glucosaminidase (NAG) and 8-hydroxydeoxyguanosine (8OHdG) and the area of caspase 3-positive tubular cells. It decreased renal expressions of medium-chain acyl-CoA dehydrogenase (MCAD), cytochrome P450 (CYP)4A, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and estrogen-related receptor α (ERRα) without change of the expression of PPARα. Clofibrate reduced proteinuria, lipid accumulation, NAG excretion and the area of caspase 3-positive tubular cells. However, albumin excretion was not reduced and 8OHdG excretion was increased. Clofibrate minimized changes in MCAD, CYP4A, PGC-1α and ERRα expressions with increased PPARα, very long-chain acyl-CoA dehydrogenase (VLCAD) and long-chain acyl-CoA dehydrogenase (LCAD) expressions.

CONCLUSION

Clofibrate is protective against renal lipotoxicity in PAN nephrosis. This study indicates that clofibrate has renoprotective effects through maintaining fatty acid metabolism in the kidney of PAN-induced nephrotic rats.

Treatment of Experimental Nephrotic Syndrome with Artesunate

The present study was designed to test the therapeutic effect of a new antimalarial drug, artesunate in experimental model of nephrotic syndrome. To induce this experimental model, Adriamycin was given once by a single intravenous injection (7.5 mg/kg) through the tail vein. Six days after injection of Adriamycin, therapeutic protocol was developed by intraperitoneally (IP) administration of 5 mg/kg artesunate (ARS). Total of IP injections were 14, of which 5 injections were made every day and 9 injections were carried out at regular 48-h intervals. Therapeutic protocol was terminated on day 28 and animals were killed on day 49. The results showed that treatment with ARS caused a significant reduction in the level of proteinuria, urine urea and urine sodium compared with nontreated controls. In addition, decrease in serum triglyceride and increase in the level of serum albumin was significant in treated group with ARS compared with nontreated controls. Moreover, treatment with ARS significantly reduced glomerular polymorphonuclear (PMN) and mononuclear cells infiltration, hypercellularity, karyorrhexis, wire loops, and hydropic change in capillary network within the renal cortex, as well as decreased hyalin casts. On the other hand, healthy controls receiving ARS showed a significant decrease in amounts of serum triglyceride, urine urea, and urine sodium and potassium compared with normal group. These data suggest that artesunate therapy can ameliorate proteinuria, and suppress the progression of glomerular lesions in experimental model of nephrotic syndrome; it may also be recommended as a lipid-lowering drug.

Presumed masitinib-induced nephrotic syndrome and azotemia in a dog

Masitinib mesylate is a tyrosine-kinase inhibitor approved for the treatment of nonresectable or recurrent, Grade 2 or 3 mast cell tumors in dogs. This report describes nephrotic syndrome and acute kidney injury attributed to masitinib and illustrates the need for regular monitoring of serum creatinine concentration, urinalysis, and urine protein:creatinine ratio during its use.

Urine and serum ghrelin, sCD80 and sCTLA-4 levels in doxorubicin-induced experimental nephrotic syndrome

BACKGROUND

Nephrotic syndrome (NS) is an immune-mediated disorder associated with hyperlipidemia. NS has been proposed to be mediated through CD80-related T cell immune response, which could be blocked using soluble cytotoxic T lymphocyte-associated s(CTLA)-4. Although ghrelin is a hormone-modulating lipid metabolism and suppressing immune system, the precise role of ghrelin in NS is not well established.

METHODS

We evaluated the levels of ghrelin, soluble CD80 (sCD80) and sCTLA4 in serum and urine in doxorubicin-induced NS in rats. We also investigated the relation between their levels and the levels of serum total cholesterol (TC), triglyceride, albumin and urine protein.

RESULTS

While urinary ghrelin levels were significantly lower in the nephrotic rats compared to the control group, serum ghrelin levels were comparable in the nephrotic and control rats. In contrast, serum and urinary sCD80 and sCTLA4 levels were higher in the nephrotic rats than the controls. The urinary ghrelin levels were negatively correlated with the levels of serum triglyceride, TC and urine protein, sCD80 and sCTLA4. The urine sCD80 levels were positively correlated with the TC, urine protein and urine sCTLA4 levels, and negatively correlated with the serum albumin. The urine sCTLA4 levels were positively correlated with the TC and urine protein levels and negatively correlated with the serum albumin levels. In regression analysis, the urine ghrelin levels significantly relate to urine sCD80 levels. Besides, hyperlipidemia in NS did not appear to be related to serum ghrelin levels.

CONCLUSION

Low urine ghrelin levels might be relevant to pathogenesis of doxorubicin-induced NS. The reduction in urine ghrelin levels might also be associated with increased levels of urine sCTLA4 and sCD80 which reflect proteinuria.

Intestinal Intravascular Large B-cell Lymphoma Mimicking Ulcerative Colitis with Secondary Membranoproliferative Glomerulonephritis

A 47-year-old woman with ulcerative colitis (UC) was admitted to our hospital for renal dysfunction and progressive anemia. Colonoscopy revealed intestinal lesions and pathological findings showed intravascular large B-cell lymphoma (IVLBCL). According to the polymerase chain reaction analysis of sequential rectal specimens, we concluded that she suffered from intestinal BCL, not UC. After chemotherapy, her renal function progressed to nephrotic syndrome. The pathological findings of renal biopsy specimens indicated membranoproliferative glomerulonephritis (MPGN). Chemotherapy was continued and led to the remission of BCL and MPGN. We herein describe the first case of intestinal IVLBCL mimicking UC with secondary MPGN.