sirolimus and Glomerulonephritis--IGA

There is a lack of new therapeutic strategies for IgA nephropathy. Low-dose sirolimus inhibits mesangial cell proliferation and renal fibrosis in animal models.. We performed a pilot, randomized controlled trial to evaluate the efficacy and safety of low-dose sirolimus in patients with a high-risk IgA nephropathy. Twenty-three patients with a glomerular filtration rate (GFR) within 30-60 mL/min and/or proteinuria >1 g/day were randomly assigned to low-dose sirolimus plus enalapril and atorvastatin (SRL group, n = 14) or enalapril plus atorvastatin (CONTROL group, n = 9). Primary composite end point was variation of haematuria, proteinuria and blood pressure. Secondary end points were isotopic GFR, renal histology evaluated by Oxford classification and safety parameters evaluated at 6 and 12 months.. Primary end point improved significantly in the SRL group at 12 months. Regarding isotopic GFR, patients included in the CONTROL group lost 8 mL/min/1.73 m(2), whereas those in the SRL arm improved 5 mL/min/1.73 m(2) (P = 0.03). Proteinuria decreased similarly in both study groups. At 1 year, SRL treatment was associated with a significant reduction of mesangial and endocapillary proliferation, whereas glomerular sclerosis, tubular atrophy and interstitial fibrosis were similar. Sirolimus was well tolerated; all patients remained on therapy at 12 months.. The addition of low-dose sirolimus to enalapril and statin is safe, stabilizes renal function and reduces glomerular proliferative lesions in patients with poor prognosis IgA nephropathy.

Topics: Adolescent; Adult; Aged; Angiotensin-Converting Enzyme Inhibitors; Atorvastatin; Blood Pressure; Case-Control Studies; Dose-Response Relationship, Drug; Drug Therapy, Combination; Enalapril; Female; Follow-Up Studies; Glomerular Filtration Rate; Glomerulonephritis, IGA; Heptanoic Acids; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Immunosuppressive Agents; Kidney Glomerulus; Male; Middle Aged; Pilot Projects; Prognosis; Prospective Studies; Pyrroles; Sirolimus; Young Adult

A 22-year-old manpresented as a refractory nephrotic syndrome with edema and proteinuria for more than one year. Physical examination revealed facial steatadenomas and periungual fibromas. Images were characterized by hamartomatous lesions in multiple organs, including the central nervous system, heart, lungs, liver, and kidneys. Gene tests verified TSC2 mutation and confirmed the diagnosis of tuberous sclerosis complex. The APOL1 mutation was positive in this patient, which indicated the possibility of steroid-resistant focal segmental glomerulonephritis. Thus, he was treated with sirolimus. Renal angiomyolipoma was shrunk, but proteinuria was not relieved (24h unine protein>10 g) and eventually led into renal insufficiency. Nondialytic therapy was initiated consequently. Losartan 50 mg/d was used to control proteinuria under the close watch of serum creatinine. A recent phone call on October 2018 failed to reachthe patient. Therefore, the follow-up information was not updated.. 患者男性，22岁。因水肿、蛋白尿1年余就诊，考虑为难治性肾病综合征。体检发现患者面部皮脂腺瘤、甲周纤维瘤，影像学显示中枢神经系统、心脏、肺、肝脏、肾脏等多系统受累，基因检查为TSC2基因突变，诊断结节性硬化症。基因检测同时发现APOL1基因突变，提示患者同时存在糖皮质激素抵抗型的局灶节段性肾小球硬化症的可能性。使用西罗莫司治疗，治疗初期肾脏血管平滑肌瘤体积缩小，但尿蛋白始终未缓解（24 h尿蛋白>10 g），最终仍发展为肾功能不全，开始非透析治疗，包括监测血压、血糖和血脂，餐中嚼服碳酸钙500 mg、3次/d，瑞舒伐他汀20 mg/d，补充维生素B(1)（10 mg/d）和叶酸（10 mg/d），使用氯沙坦50 mg/d控制尿蛋白并监测血肌酐变化。2018年10月电话随访未联系到患者，未能获得治疗近况。.

Topics: Angiomyolipoma; Apolipoprotein L1; Creatinine; Female; Glomerulonephritis, IGA; Humans; Kidney Failure, Chronic; Kidney Neoplasms; Losartan; Male; Mutation; Nephrotic Syndrome; Proteinuria; Sirolimus; Tuberous Sclerosis; Tuberous Sclerosis Complex 2 Protein; Young Adult

The pathogenesis of the development of IgA nephropathy has not been clear up to now. At present, some studies revealed that the mTOR pathway may participate in IgA nephropathy; however, the mechanism has not been systematically studied. In this study, we established an IgAN rat model to investigate the protective effects of rapamycin as a new type of immunosuppressant, as well as its therapeutic mechanisms.. After the establishment of IgA nephropathy model, rats were treated with different concentrations of rapamycin, and the protective effect of different concentrations of rapamycin on renal function of the rats was observed. The deposition of IgA was observed by immunofluorescence. The kidney expression of Akt and p70S6k proteins in mTOR pathway was examined using the western blot assay after rapamycin treatment.. Morphology and immunofluorescence confirmed that the rat model of IgA nephropathy was successfully established. In particular, the level of proteinuria decreased with the increase of the dose of rapamycin, as well as the deposition of IgA in glomeruli. Moreover, the western blot analysis indicated that the expression of p70S6K in the downstream of mTOR pathway decreased and the upstream protein AKT of the mTOR pathway was overexpressed in the rats model.. We found that rapamycin has protective effects in the IgA nephropathy rat model in a dose-dependent manner. In addition, the result of western blot assay suggested that rapamycin may display its therapeutic effects through interfering the AKT-mTOR-p70S6K signaling pathway.

Topics: Animals; Disease Models, Animal; Disease Progression; Glomerulonephritis, IGA; Humans; Immunoglobulin A; Immunosuppressive Agents; Kidney Glomerulus; Male; Proto-Oncogene Proteins c-akt; Rats; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome

Backgroud/Aims: The aim of this study was to investigate the potential renoprotective effect of rapamycin on the autophagy of podocytes treated with the supernatant of mesangial cells cultured with aggregated IgA1 (aIgA1) from immunoglobulin A nephropathy (IgAN) patients.. Monomeric IgA1 (mIgA1) was isolated from the serum of IgAN patients or healthy volunteers, and then transformed to aIgA1 by heating. Subsequently, the aIgA1-mesangial cell supernatant was prepared by collecting the medium of mouse mesangial cells (MSC1097) cultured with aIgA1 (100 mg/L) from different IgAN patients or healthy volunteers for 48 h. Subsequently mouse podocytes (MPC5) were exposed to the supernatant of the aIgA1-mesangial cells for 24 h, using 100 mg/L aIgA1 from healthy volunteers as the control group or 100 mg/L aIgA1 from IgAN patients as the IgANs group, in RPMI 1640 medium. The MPC5 cells in the IgANs+Rap group were cultured with rapamycin (10 nmol/L) and the supernatant of MSC-1097 cells cultured with aIgA1 from IgAN patients in RPMI 1640 medium. Autophagy was assessed by western blot analysis (LC3, p62), electron microscopy, and immunofluorescence staining (LC3, p62, and CD63). The apoptosis of podocytes was evaluated by flow cytometry, and the expression of apoptosis-associated proteins cleaved-caspase-3 and caspase-3 were determined by western blot analysis.. Deficient autophagy, which was evident by decreased LC3-II and CD63 levels, caused accumulation of p62, and fewer autophagosomes were observed in the MPC5 cells cultured with the IgAN supernatant, along with stronger expression of cleaved caspase-3 and a higher apoptosis rate. Inhibition of autophagy was alleviated in the IgANs+Rap group. The LC3-II/LC3-I ratio increased by almost 30%, the accumulated p62 amount was reduced by 50%, and the number of autophagosomes per podocyte increased to about 7 times that of the IgAN groups. These results were confirmed by immunofluorescence staining. In addition, the apoptosis rate of MPC5 cells decreased from 19.88% in the IgAN group to 16.78% in the IgANs+Rap group, which was accompanied by a weaker expression level of cleaved caspase-3.. Rapamycin can reduce the apoptosis of podocytes by inducing autophagy in IgAN.

Topics: Animals; Apoptosis; Apoptosis Regulatory Proteins; Autophagy; Cells, Cultured; Glomerulonephritis, IGA; Humans; Mesangial Cells; Mice; Podocytes; Sirolimus

IgA nephropathy (IgAN) has been considered to be the most frequent form of primary glomerulonephritis that occurs worldwide with a variety of factors involved in its occurrence and development. The impact of autophagy in IgAN, however, remains partially unclear. This study was designed to investigate the effects of rapamycin in an IgAN model.. After establishing an IgAN rat model, SD rats were divided into 4 groups: control, control + rapamycin, IgAN, IgAN + rapamycin. Proteinuria and the pathological changes and the level of autophagy of kidney were texted. Identify the expression of phosphorylation and total mammalian target of rapamycin (mTOR) and s6k1 as well as cyclin D1 in the kidney of rats through Western blot and immunohistochemistry.. With rapamycin treatment, we observed a significant reduction in the progression of proteinuria as well as alleviation of pathological lesions in IgAN rats. Besides, autophagy was inhibited, while the mTOR/S6k1 pathway was activated and expression of cyclin D1 was increased in IgAN. Rapamycin treatment increased autophagy and decreased the expression of cyclin D1.. These results may suggest that mTOR-mediated autophagy inhibition may result in mesangial cell proliferation in IgAN.

Topics: Animals; Autophagy; Cell Proliferation; Cyclin D1; Disease Models, Animal; Glomerulonephritis, IGA; Humans; Immunohistochemistry; Immunosuppressive Agents; Mesangial Cells; Microscopy, Electron; Proteinuria; Rats; Rats, Sprague-Dawley; Ribosomal Protein S6 Kinases; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Galactose-deficient IgA1 (Gd-IgA1) and IgA-IgG complexes are known to play an important role in the pathogenesis of IgA nephropathy (IgAN). We aimed therefore to determine the impact of immunosuppression on the serum levels of Gd-IgA1, total IgA1 and IgA-IgG complexes in IgAN patients. In a retrospective study, serum samples from IgAN patients collected before transplantation (t0) and at 3- and 6-month posttransplant (t3 & t6) were used to measure the levels of Gd-IgA1, total IgA1 and IgA-IgG complexes. The area under the curves (AUC) of immunosuppressants was calculated by the plot of plasma trough level or dosage of each immunosuppressant versus time and was interpreted as the extent of drug exposure. Thirty-six out of 64 IgAN patients, who underwent kidney transplantation between 2005 and 2012, were enrolled. From t0 to t3, serum Gd-IgA1 and total IgA1 decreased significantly (24.7 AU (18.6-36.1) to 17.2 (13.1-29.5) (p<0.0001); 4.1 mg/ml (3.6-5.1) to 3.4 (3.0-4.1) (p = 0.0005)), whereas IgA-IgG complexes remained similar. From t3 to t6, Gd-IgA1 and IgA-IgG complexes significantly increased (17.2 AU (13.1-29.5) to 23.9 (16.8-32.0) (p = 0.0143); OD 0.16 (0.06-0.31) to 0.26 (0.14-0.35) (p = 0.0242)), while total IgA1 remained similar. According to median regression analysis, AUC of prednisone t0-6 was significantly associated with the decrease of Gd-IgA1 t0-6 (P = 0.01) and IgA1 t0-6 (p = 0.002), whereas AUC of tacrolimus t0-6 was associated with the decrease of IgA1 t0-6 (p = 0.02). AUC of prednisone t0-3 was associated with the decrease of IgA-IgG complexes t0-3 (p = 0.0036). The association of AUC prednisone t0-6 with Gd-IgA1 t0-6 remained highly significant after adjustment for other immunosuppressants (p = 0.0036). Serum levels of Gd-IgA1, total IgA1 and IgA-IgG in patients with IgAN vary according to the changing degrees of immunosuppression. The exposure to prednisone most clearly influenced the serum levels of Gd-IgA1.

Topics: Antibodies, Monoclonal; Basiliximab; Drug Therapy, Combination; Female; Galactose; Glomerulonephritis, IGA; Humans; Immunoglobulin A; Immunoglobulin G; Immunosuppressive Agents; Kidney; Male; Middle Aged; Mycophenolic Acid; Prednisone; Recombinant Fusion Proteins; Sirolimus; Tacrolimus

IgA nephropathy is the most frequent type of glomerulonephritis worldwide. The role of cell cycle regulation in the pathogenesis of IgA nephropathy has been studied. The present study was designed to explore whether rapamycin ameliorates IgA nephropathy via cell cycle-dependent mechanisms. After establishing an IgA nephropathy model, rats were randomly divided into four groups. Coomassie Brilliant Blue was used to measure the 24-h urinary protein levels. Renal function was determined using an autoanalyzer. Proliferation was assayed via Proliferating Cell Nuclear Antigen (PCNA) immunohistochemistry. Rat mesangial cells were cultured and divided into the six groups. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) and flow cytometry were used to detect cell proliferation and the cell cycle phase. Western blotting was performed to determine cyclin E, cyclin-dependent kinase 2, p27(Kip1), p70S6K/p-p70S6K, and extracellular signal-regulated kinase 1/2/p- extracellular signal-regulated kinase 1/2 protein expression. A low dose of the mammalian target of rapamycin (mTOR) inhibitor rapamycin prevented an additional increase in proteinuria, protected kidney function, and reduced IgA deposition in a model of IgA nephropathy. Rapamycin inhibited mesangial cell proliferation and arrested the cell cycle in the G1 phase. Rapamycin did not affect the expression of cyclin E and cyclin-dependent kinase 2. However, rapamycin upregulated p27(Kip1) at least in part via AKT (also known as protein kinase B)/mTOR. In conclusion, rapamycin can affect cell cycle regulation to inhibit mesangial cell proliferation, thereby reduce IgA deposition, and slow the progression of IgAN.

Topics: Animals; Blotting, Western; Cell Cycle; Cell Proliferation; Disease Models, Animal; Flow Cytometry; Fluorescent Antibody Technique; Glomerulonephritis, IGA; Immunohistochemistry; Immunosuppressive Agents; Male; Mesangial Cells; Rats; Rats, Sprague-Dawley; Sirolimus

IgA nephropathy (IgAN) is one of the most frequent forms of glomerulonephritis, and 20 to 40% of patients progress to end-stage renal disease (ESRD) within 20 years of disease onset. However, little is known about the molecular pathways involved in the altered physiology of mesangial cells during IgAN progression. This study was designed to explore the role of mTOR signaling and the potential of targeted rapamycin therapy in a rat model of IgAN. After establishing an IgA nephropathy model, the rats were randomly divided into four groups: control, control+rapamycin, IgAN and IgA+rapamycin. Western blotting and immunohistochemistry were performed to determine phospho-Akt, p70S6K and S6 protein levels. Coomassie Brilliant Blue was utilized to measure 24-h urinary protein levels. The biochemical parameters of the rats were analyzed with an autoanalyzer. To evaluate IgA deposition in the glomeruli, FITC-conjugated goat anti-rat IgA antibody was used for direct immunofluorescence. Cellular proliferation and the mesangial matrix in glomeruli were assayed via histological and morphometric procedures. Our results showed that p70S6K, S6 and Akt phosphorylation were significantly upregulated in IgAN rats, and rapamycin effectively inhibited p70S6K and S6 phosphorylation. A low dose of the mTOR inhibitor rapamycin reduced proteinuria, inhibited IgA deposition, and protected kidney function in an IgAN rat model. Low-dose rapamycin treatment corresponded to significantly lower cellular proliferation rates and a decreased mesangial matrix in the glomeruli. In conclusion, the Akt/mTOR/p70S6K pathway was activated in IgAN, and our findings suggested that rapamycin may represent a viable option for the treatment of IgAN.

Topics: Animals; Cell Proliferation; Glomerulonephritis, IGA; Immunoglobulin A; Kidney Diseases; Kidney Glomerulus; Male; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Ribosomal Protein S6 Kinases, 70-kDa; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

IgA nephropathy (IgAN) is the most frequent glomerulonephritis worldwide. Different therapeutic approaches have been tested against IgAN. The present study was designed to explore the renoprotective potential of low-dose mammalian target of rapamycin (mTOR) inhibitor rapamycin in an IgAN rat model and the possible mechanism of action.. After establishing an IgAN model, the rats were randomly divided into four groups: control, control with rapamycin treatment, IgAN model, and IgAN model with rapamycin treatment. Coomassie Brilliant Blue was utilized to measure 24-hour urinary protein levels. Hepatic and renal function was determined with an autoanalyzer. Proliferation was assayed via 5-bromo-2'-deoxyuridine incorporation. Real-time PCR and immunohistochemistry were utilized to detect the expression of α-SMA, collagen I, collagen III, TGF-β1 and platelet-derived growth factor. Western blotting and immunohistochemistry were performed to determine p-S6 protein levels.. Low-dose mTOR inhibitor rapamycin prevented an additional increase in proteinuria and protected kidney function in a model of IgAN. Rapamycin directly or indirectly interfered with multiple key pathways in the progression of IgAN to end-stage renal disease: (1) reduced the deposition of IgA and inhibited cell proliferation; (2) decreased the expression of fibrosis markers α-SMA and type III collagen, and (3) downregulated the expression of the profibrotic growth factors platelet-derived growth factor and TGF-β1. The expression of p-S6 was significantly elevated in IgAN rats.. The mTOR pathway was activated in IgAN rats and the early application of low-dose mTOR inhibitor rapamycin may slow the renal injury of IgAN in rats.

Topics: Animals; Cell Proliferation; Disease Models, Animal; Disease Progression; Fibrosis; Glomerulonephritis, IGA; Immunosuppressive Agents; Kidney; Kidney Glomerulus; Liver; Male; Platelet-Derived Growth Factor; Rats; Rats, Sprague-Dawley; Sirolimus; Time Factors; TOR Serine-Threonine Kinases; Transforming Growth Factor beta

Topics: Everolimus; Female; Glomerulonephritis, IGA; Humans; Immunosuppressive Agents; Kidney Transplantation; Middle Aged; Optic Nerve Diseases; Posterior Leukoencephalopathy Syndrome; Postoperative Complications; Sirolimus; Vision, Ocular

Herein we have described the case of a male renal transplant recipient who developed drug fever apparently related to sirolimus. He had been stable under an immunosuppressive regimen of tacrolimus and mycophenolate mofetil, but developed acute cellular rejection at 5 years after transplantation due to noncompliance. Renal biopsy showed marked interstitial fibrosis, and immunosuppression was switched from mycophenolate to sirolimus, maintaining low tacrolimus levels. One month later he was admitted to our hospital for investigation of intermittently high fever, fatigue, myalgias, and diarrhea. Physical examination was unremarkable and drug levels were not increased. Lactic dehydrogenase and C-reactive protein were increased. The blood cell count and chest radiographic findings were normal. After extensive cultures, he was started on broad-spectrum antibiotics. Inflammatory markers and fever worsened, but diarrhea resolved. All serologic and imaging tests excluded infection, immune-mediated diseases, and malignancy. After 12 days antibiotics were stopped as no clinical improvement was achieved. Drug fever was suspected; sirolimus was replaced by mycophenolate mofetil. Fever and other symptoms disappeared after 24 hours; inflammatory markers normalized in a few days. After 1 month the patient was in good health with stable renal function. Although infrequent, the recognition of drug fever as a potential side effect of sirolimus may avoid unnecessary invasive diagnostic procedures. Nevertheless, exclusion of other common causes of fever is essential.

Topics: Fever; Glomerulonephritis, IGA; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Mycophenolic Acid; Prednisone; Radiography, Thoracic; Sirolimus; Treatment Outcome