Drug-induced nephrotoxicity in children is dependent upon the histological, anatomical and physiological features of their kidneys and the structural and functional characteristics of drugs. The kidney is mainly composed of microvascular network and tubulointerstitial tissue, so drug-induced nephrotoxicity is usually manifested by interstitial nephropathy. The mechanisms of drug-induced nephrotoxicity include cytotoxicity (necrosis or apoptosis), ischemic injury, and immunological injury. Individual drugs cause renal damage by various mechanisms due to differences in chemical structure and pharmacology. This article reviews the main features of nephrotoxicity induced by common antibiotics (cephalosporins, aminoglycosides, vancomycin, carbapenems and amphotericin B), non-steroidal anti-inflammatory drugs, and cyclosporine A.
Anti-Bacterial Agents ; toxicity ; Anti-Inflammatory Agents, Non-Steroidal ; toxicity ; Child ; Cyclosporine ; toxicity ; Humans ; Kidney Diseases ; chemically induced

Sirolimus (SRL) is a promising drug for replacing calcineurin inhibitors. We performed this study to determine the optimal time of conversion from cyclosporine (CsA) to SRL in an experimental model of chronic CsA nephropathy. Three separate studies were performed. In the first study, SRL was given to rats with or without CsA for 4 weeks. In the second study, rats were treated initially with CsA for 1 week, and then switched to SRL (early conversion). In the third study, CsA was given for 4 weeks and then replaced by SRL for 4 weeks treatment of CsA (late conversion). The influence of SRL on CsA-induced renal injury was evaluated by assessing renal function, histopathology (interstitial inflammation and fibrosis), and apoptotic cell death. Combined CsA and SRL treatment significantly impaired renal function, increased apoptosis, and interstitial fibrosis and inflammation compared with CsA or SRL treatment alone. Early conversion to SRL did not change renal function, histopathology, or apoptosis compared with early CsA withdrawal. By contrast, late conversion to SRL significantly aggravated these parameters compared with late CsA withdrawal. In conclusion, early conversion from CsA to SRL is effective in preventing CsA-induced renal injury in a setting of CsA-induced renal injury.
Animals ; Apoptosis/drug effects ; Chronic Disease ; Cyclosporine/*toxicity ; Immunosuppressive Agents/*pharmacology ; Intestines/drug effects/pathology ; Kidney Diseases/chemically induced/*pathology ; Male ; Models, Animal ; Rats ; Rats, Sprague-Dawley ; Sirolimus/*pharmacology

BACKGROUND/AIMS: Hypoalbuminemia occurs frequently in renal transplant recipients immediately after renal transplantation. We studied the regulation of hepatic albumin synthesis by cyclosporin A (CsA) in Huh7 cells. METHODS: Huh7 cells were incubated with various concentrations of CsA for 4, 8, 16, and 24 hours. Albumin was measured in Huh7 cell-conditioned medium by sandwich enzyme-linked immunosorbent assay and Western blot. Albumin mRNA expression was analyzed by Northern blotting in CsA-treated cells. RESULTS: CsA (10(-7)-10(-4) M) inhibited albumin synthesis in Huh7 cells in a dose- dependent manner. A Western blot analysis for albumin in the conditioned medium released from CsA-treated (10(-7)-10(-5) M) cells also showed significant inhibition of albumin synthesis in a dose-dependent manner. Vehicle (olive oil) did not affect albumin synthesis. In contrast, a Northern blot analysis revealed no inhibition of albumin mRNA expression by CsA at any time point from 1-24 hours, indicating that the inhibition of albumin synthesis occurred at the translational level. CONCLUSIONS: Our results suggest that inhibition of hepatic albumin synthesis by high dose CsA contributes to the hypoalbuminemia in renal transplant recipients.
Blotting, Northern ; Blotting, Western ; Carcinoma, Hepatocellular/genetics/*metabolism ; Cell Line, Tumor ; Cell Survival/drug effects ; Culture Media, Conditioned/metabolism ; Cyclosporine/*pharmacology/toxicity ; Dose-Response Relationship, Drug ; Enzyme-Linked Immunosorbent Assay ; Gene Expression Regulation, Neoplastic/drug effects ; Humans ; Hypoalbuminemia/chemically induced/metabolism ; Immunosuppressive Agents/*pharmacology/toxicity ; Liver Neoplasms/genetics/*metabolism ; RNA, Messenger/metabolism ; Serum Albumin/genetics/*metabolism ; Time Factors

OBJECTIVE: To determine the expression and mechanism of osteoactivin (OA) in the kidney by establishing SD rat model of acute cyclosporine A (CsA) toxicity. METHODS: SD rats were fed with normal diet for a week, which they were then randomly divided into 3 groups: an experimental group (gavage with cycloporin A and olive oil), a vector group (gavage with olive oil), and a control group (gavage with normal saline). SD rats were killed 2 days, 1 week, or 2 weeks after the gavage to examine the serum creatinine (SCr) and body weight. HE staining was used to detect the kidney histopathological change. Immunohistochemistry was used to observe the staining degree and area of OA. Western blot was used to detect the OA protein.The mRNA expressions of the OA, matrix metalloproteinase-13(MMP-13), and collagen type III(Col III) were examined by RT-PCR. RESULTS: The body weight and SCr of the rats in the experimental group 1 week and 2 days after the gavage had no significant difference compared with the vector group or the control group (P>0.05).On the end of 2nd week, the rats' body weight was significantly reduced, and SCr significantly increased compared with the vector group or the control group (P<0.001).The main histopathological changes in the experimental group were inflammatory cell infiltration, vacuolar degeneration of interstitial cells, or tubular epithelial cell necrosis. Intense OA expression located in the tubular epithelium and interstitial fibroblasts in the kidney of the experimental group was observed by immunohistochemistry. After CsA gavage, the relative mRNA expressions of OA, MMP-13, and Col III significantly increased with time. Western blot did not find the expression of OA protein in the control and the vector group, which increased with time in the experimental group. CONCLUSION OA expresses in the kidney of SD rats after acute CsA toxicity and mainly expresses in the tubular epithelial cells and renal interstitium. OA is more sensitive to the damage of kidney tissue caused by CsA than by SCr. The early-phase up-regulation of OA expression in the tubular epithelium in response to renal injury caused by acute CsA toxicity might play a key role in triggering the renal interstitial fibrosis via activating expression of MMPs and collagen remodeling in SD rats.
Animals ; Collagen Type III ; genetics ; metabolism ; Cyclosporine ; toxicity ; Epithelial Cells ; metabolism ; pathology ; Immunosuppressive Agents ; toxicity ; Kidney Diseases ; chemically induced ; metabolism ; pathology ; Kidney Tubules ; metabolism ; pathology ; Male ; Matrix Metalloproteinase 13 ; genetics ; metabolism ; Membrane Glycoproteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo establish a new rat model of chronic cyclosporine A nephrotoxicity and explore its features.

METHODSTotally 24 male SD rats were equally randomized divided into 3 groups: sham-adrenalectomized (sham-ADX) group, ADX group and ADX plus cyclosporine A (CsA) group. Rats in ADX and CsA group first underwent adrenalectomy, followed by the administration of placebo or dexamethasone, respectively. Rats in sham-ADX group received sham adrenalectomy and distilled water as control. Six weeks later, all rats were sacrificed and the following indicators were evaluated: urine protein excretion, creatinine clearance, aldosterone level in serum and urine, aldosterone level and its synthase CYP11B2 gene expression in kidney, serum natrium and potassium, urine natrium and potassium excretion, and tubulointerstitial fibrosis by masson trichrome stain.

RESULTSIn ADX and CsA group, serum and urine aldosterone were undetectable on the second post-operative day, with other observations including natriuresis, hyponatremia, decreased urine potassium excretion, and hyperpotassemia, suggesting that adrenals were removed intact and the adrenalectomy was successful. Rats in CsA group showed increased urine protein, decreased creatinine clearance and tubulointerstitial fibrosis, suggesting that a model of chronic CsA nephrotoxicity was successfully established. At the endpoint, serum potassium, serum aldosterone, urine potassium and urine aldosterone excretion partially retrieved. Natrium in serum and urine was not significant different between ADX group/CsA group and sham-ADX group. Local renal aldosterone and its gene expression were remarkably upregulated.

CONCLUSIONSWe successfully established a new rat model of chronic CsA nephrotoxicity by adrenalectomy without low sodium diet. After adrenalectomy, local renal aldosterone in kidney may compensate for circulatory aldosterone deficit to maintain electrolyte balance.

Acute Kidney Injury ; chemically induced ; Adrenalectomy ; Aldosterone ; metabolism ; Animals ; Cyclosporine ; toxicity ; Disease Models, Animal ; Immunosuppressive Agents ; toxicity ; Kidney ; drug effects ; metabolism ; pathology ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the gene expression of MAPEG in the cortex of concanavalin A (Con A)-induced mouse immune inflammatory model and the effect of cyclosporine A (Cs A).

METHODSMale Balb/c mouse immune inflammation model was developed by intravenous injection of Con A (20 mg/kg). Cs A (150 mg/kg) was intravenously infected prior to Con A administration. The MAPEG expressions were determined by RT-PCR.

RESULTmGST1, mGST3, LTC(4)S, FLAP and mPGES-1 were detected by RT-PCR but not mGST2. Eight hours after Con A treatment, mGST1 level was up-regulated to 1.2 approximately 1.5 folds of control with or without Cs A treatment. mGST3ìLTC(4)S, FLAP and mPGES-1 mRNA levels were not influenced by Con A administration.

CONCLUSIONImmune mechanism may be not involved in mGST1 up-regulation in this model and Con A does not alter arachidonic acid metabolism in cortex.

5-Lipoxygenase-Activating Proteins ; Animals ; Brain ; metabolism ; Carrier Proteins ; genetics ; metabolism ; Concanavalin A ; toxicity ; Cyclosporine ; pharmacology ; Eicosanoids ; metabolism ; Glutathione ; metabolism ; Glutathione Transferase ; genetics ; metabolism ; Intramolecular Oxidoreductases ; genetics ; metabolism ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred BALB C ; Prostaglandin-E Synthases

PURPOSE: We recently reported that rosiglitazone (RGTZ), a peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has a protective effect against cyclosporine (CsA)- induced renal injury. Here we report the effect of RGTZ on peroxisome proliferator-activated receptor gamma (PPARgamma) expression in an experimental model of chronic cyclosporine (CsA) nephropathy. MATERIALS AND METHODS: Chronic CsA nephropathy was induced in Sprague-Dawley rats by administering CsA (15mg/kg per day) for 28 days, and control rats were treated with vehicle (VH group, olive oil 1mL/kg per day) for 28 days. RGTZ (3mg/kg) was concurrently administered via gavage to the CsA and VH groups. Expression of PPARgamma mRNA and protein was evaluated with RT-PCR, immunohistochemistry, and immunoblotting. RESULTS: PPARgamma mRNA expression was similar to the level of PPARgamma protein constitutively expressed in the kidneys of the VH treated rats, with expression in the glomerular epithelial, distal tubular cells, and collecting tubular cells. PPARgamma protein expression in CsA-treated rat kidneys was significantly less than in the VH group. However, concomitant administration of RGTZ restored PPARgamma protein expression in the kidneys of the CsA- reated rats. CONCLUSION: Exogenous administration of RGTZ treatment upregulates PPARgamma expression and that this mechanism may play a role in protecting against CsA-induced renal injury.
Transcription, Genetic/*drug effects ; Thiazolidinediones/*pharmacology ; Rats, Sprague-Dawley ; Rats ; RNA, Messenger/*genetics ; Protein Biosynthesis/*drug effects ; PPAR gamma/*genetics ; Male ; Kidney Diseases/genetics/pathology/*prevention & control ; Gene Expression Regulation/*drug effects ; Disease Models, Animal ; Cyclosporine/*toxicity ; Animals

OBJECTIVETo explore the gene expressions of LTC4 synthase homologs in concanavalin A (Con A)-induced mouse hepatitis and regulation role of cyclosporine A (Cs A) treatment.

METHODSMale Balb/c mouse liver injury model was developed by iv injection of Con A (20 mg/kg) and protected by Cs A pretreatment (150 mg/kg) before Con A administration. Blood samples were collected at indicated times after Con A treatment with or without Cs A pretreatment. Liver damage was assessed by serum transaminase ALT and AST measurement and histological evaluation. Meantime, three LTC4 synthase homolog gene expressions were determined by RT-PCR.

RESULTSSerum ALT and AST upregulation were accompanied with histological damage at 2 h after Con A administration, and further aggravated at 8 h. mGST2 gene expression increased 1.7 fold at 2 h and 1.9 fold at 8 h, while the expression of LTC4 S and mGST3 changed little. Pretreatment with Cs A prevented mouse liver from injury by Con A and partly inhibited the mGST2 gene expression upregulation.

CONCLUSIONSAdministration of Con A in mouse lead to a significant increase of mGST2 gene expression without any significant effect on LTC4 S and mGST3 mRNA levels. Cs A pretreatment results in protection of liver damage, whereas fails to fully inhibit the increase of mGST2 gene expression.

Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Chemical and Drug Induced Liver Injury ; enzymology ; etiology ; prevention & control ; Concanavalin A ; administration & dosage ; toxicity ; Cyclosporine ; pharmacology ; Gene Expression Regulation, Enzymologic ; genetics ; Glutathione Transferase ; genetics ; Hepatitis, Animal ; chemically induced ; enzymology ; prevention & control ; Immunosuppressive Agents ; pharmacology ; Injections, Intravenous ; Isoenzymes ; genetics ; Male ; Mice ; Mice, Inbred BALB C ; Reverse Transcriptase Polymerase Chain Reaction

PURPOSE: Local activation of the complement system plays a role in target organ damage. The aim of our study was to investigate the influence of cyclosporine (CsA)- induced renal injury on the complement system in the kidney. MATERIALS AND METHODS: Mice fed a low salt (0.01%) diet were treated with vehicle (VH, olive oil, 1mL/kg/day) or CsA (30mg/kg/day) for one or four weeks. Induction of chronic CsA nephrotoxicity was evaluated with renal function and histomorphology. Activation of the complement system was assessed through analysis of the expression of C3, C4d, and membrane attack complex (MAC), and the regulatory proteins, CD46 and CD55. CsA treatment induced renal dysfunction and typical morphology (tubulointerstitial inflammation and fibrosis) at four weeks. RESULTS: CsA-induced renal injury was associated with increased the expression of C3, C4d, and MAC (C9 and upregulation of complement regulatory proteins (CD 46 and CD55). Immunohistochemistry revealed that the activated complement components were mainly confined to the injured tubulointerstitium. CONCLUSION: CsA-induced renal injury is associated with activation of the intrarenal complement system.
Animals ; Antigens, CD45/analysis ; Antigens, CD46/analysis ; Antigens, CD55/analysis ; Complement C3/analysis ; Complement C4b/analysis ; Complement Membrane Attack Complex/analysis ; Complement System Proteins/*analysis ; Cyclosporine/*toxicity ; Disease Models, Animal ; Immunity, Innate/drug effects ; Immunoblotting ; Immunohistochemistry ; Immunosuppressive Agents/toxicity ; Kidney/*drug effects/immunology/pathology ; Kidney Diseases/*chemically induced/immunology ; Mice ; Microscopy, Confocal ; Peptide Fragments/analysis

OBJECTIVETo reconstitute an Alzheimer's disease model by administering bradykinin (BK) or cyclosporine A (CSA) to the rat hippocampus.

METHODSBK or CSA was administered to the rat hippocampus using a stereotaxic apparatus. The behavior of the rats was observed with an electronic attack jump platform. The phosphorylation of Tau protein was examined through immunohistochemical assay.

RESULTSBehavior studies showed that an obvious disturbance in learning and memory was seen in BK injected rats.No obvious dysfunction was observed in CSA injected rats. The results obtained by immunohistochemical assay indicated that the staining of M4, 12E8, paired helical filament-1 (PHF-1) and calcium/calmodulin-dependent protein kinase II (CaMKII) was stronger, and that of Tau-1 was weaker in BK injected rats compared with the control group. We also found that the binding of M4 and PHF-1 but not 12E8 to Tau was significantly increased in CSA injected rats. As for BK injection, binding of Tau-1 to Tau was decreased after CSA injection.

CONCLUSIONTo our knowledge, this is the first data showing in vivo that the activation of CaMKII induces both Alzheimer-like Tau phosphorylation and behavioral disturbances.

Alzheimer Disease ; etiology ; Animals ; Bradykinin ; toxicity ; Calcium ; metabolism ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; Calcium-Calmodulin-Dependent Protein Kinases ; metabolism ; Cyclosporine ; toxicity ; Disease Models, Animal ; Hippocampus ; drug effects ; metabolism ; Immunohistochemistry ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; tau Proteins ; analysis ; metabolism