This study aims to reveal the endogenous metabolic characteristics of acteoside in the young rat model of purinomycin aminonucleoside nephropathy(PAN) by non-targeted urine metabolomics and decipher the potential mechanism of action. Biochemical indicators in the urine of rats from each group were determined by an automatic biochemical analyzer. The potential biomarkers and related core metabolic pathways were identified by ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) combined with principal component analysis(PCA) and orthogonal partial least squares-discriminant analysis(OPLS-DA). MetaboAnalyst 5.0 was used to establish the receiver operating characteristic(ROC) curve for evaluating the clinical diagnostic performance of core metabolites. The results showed that acteoside significantly decreased urinary protein-to-creatinine ratio in PAN young rats. A total of 17 differential metabolites were screened out by non-targeted urine metabolomics in PAN young rats and they were involved in phenylalanine metabolism and phenylalanine, tyrosine and tryptophan biosynthesis. Thirtten differential metabolites were screened by acteoside intervention in PAN young rats, and they were involved in phenylalanine metabolism and arginine and proline metabolism. Among them, leucylproline and acetophenone were the differential metabolites that were significantly recovered after acteoside treatment. These pathways suggest that acteoside treats PAN in young rats by regulating amino acid metabolism. The area under the curve of two core biomarkers, leucylproline and acetophenone, were both greater than 0.9. In summary, acteoside may restore amino acid metabolism by regulating endogenous differential metabolites in PAN young rats, which will help to clarify the mechanism of acteoside in treating chronic glomerulonephritis in children. The characteristic biomarkers screened out have a high diagnostic value for evaluating the treatment of chronic glomerulonephritis in children with acteoside.
Humans ; Child ; Rats ; Animals ; Puromycin Aminonucleoside ; Metabolomics/methods* ; Biomarkers/urine* ; Chromatography, High Pressure Liquid/methods* ; Acetophenones ; Glomerulonephritis ; Phenylalanine ; Amino Acids

Nephrotic syndrome (NS) is a kidney disease characterized by hypertriglyceridemia, massive proteinuria, hypo-albuminemia and peripheral edema. Sinkihwan-gamibang (SKHGMB) was recorded in a traditional Chinese medical book named "Bangyakhappyeon ()" and its three prescriptions Sinkihwan, Geumgwe-sinkihwan, and Jesaeng-sinkihwan belong to Gamibang. This study confirmed the effect of SKHGMB on renal dysfunction in an NS model induced by puromycin aminonucleoside (PAN). The experimental NS model was induced in male Sprague Dawley (SD) rats through injection of PAN (50 mg·kg^-1)via the femoral vein. SKHGMB not only reduced the size of the kidneys increased due to PAN-induced NS, but also decreased proteinuria and ascites. In addition, SKHGMB significantly ameliorated creatinine clearance, creatinine, and blood urea nitrogen. SKHGMB relieved glomeruli dilation and tubules fibrosis in the glomeruli of the NS model. SKHGMB inhibited the protein and mRNA levels of the NLRP3 inflammasome including NLRP3, ASC, and pro-caspase-1 in NS rats. SKHGMB reduced the protein and mRNA levels of fibrosis regulators in NS rats. The results indicated that SKHGMB exerts protective effects against renal dysfunction by inhibiting of renal inflammation and fibrosis in NS rats.
Animals ; Kidney ; Male ; Nephrotic Syndrome/drug therapy* ; Proteinuria/metabolism* ; Puromycin Aminonucleoside/toxicity* ; Rats ; Rats, Sprague-Dawley

BACKGROUND: Puromycin aminonucleoside (PAN) is a known podocytotoxin. PAN-induced nephrosis is a widely used animal model for studying human idiopathic nephrotic syndrome. Abnormal protein accumulation associated with podocyte-specific endoplasmic reticulum (ER) stress damages cells structurally and functionally, which in turn induces apoptosis and severe proteinuria. In the present study, we investigated the effect of PAN on ER stress and apoptosis in podocytes in vitro. METHODS: Mouse podocytes were cultured and treated with various concentrations of PAN. ER stress markers were then evaluated by western blotting, and apoptosis was evaluated by fluorescence-activated cell sorting (FACS) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays. RESULTS: PAN treatment increased ER stress markers such as activating transcription factor (ATF) 6α and caspase-12 in a dose-dependent manner at 12 and 24 hours, respectively. These markers were reduced by chemical chaperones, such as sodium 4-phenylbutyric acid and tauroursodeoxycholic acid. PAN treatment also increased 78 kD glucose-regulated protein (GRP78)/binding immunoglobulin protein (BiP) at the earlier stage of 12 hours. PAN significantly induced podocyte apoptosis in concentration- and time-dependent manners, as seen using FACS and TUNEL assays. This result was improved by Nox4 siRNA, ATF6 siRNA, and chemical chaperones. LY294002, a PI3-kinase inhibitor, significantly boosted ER stress and apoptosis. PAN-induced ER stress increased oxidative stress and subsequently induced apoptosis, and could be mitigated by inhibition of PI3-kinase signaling. CONCLUSION: Our findings suggest that PAN induces ER stress in podocytes mainly through the GRP78/BiP, ATF6α, and caspase-12 pathways, which trigger apoptosis via induction of oxidative stress. This stress is mitigated by inhibiting PI3-kinase signaling.
Animals ; Apoptosis* ; Blotting, Western ; Caspase 12 ; DNA Nucleotidylexotransferase ; Endoplasmic Reticulum Stress* ; Endoplasmic Reticulum* ; Flow Cytometry ; Humans ; Immunoglobulins ; In Situ Nick-End Labeling ; In Vitro Techniques ; Mice ; Models, Animal ; Nephrosis ; Nephrotic Syndrome ; Oxidative Stress ; Phosphatidylinositol 3-Kinases ; Podocytes* ; Proteinuria ; Puromycin Aminonucleoside* ; Puromycin* ; RNA, Small Interfering ; Sodium ; Transcription Factors

OBJECTIVETo observe the effect of Wenyang Huoxue Lishui Recipe (WHLR) containing serum on the expression of cathepsin L (CatL) in puromycin aminonucleoside-induced injury of mouse glomerular podocytes.

METHODSMouse podocyte cells (MPCs) in vitro cultured were divided into the normal control group, the model group, the dexamethasone (DEX) group, 10% WHLR containing serum group, 20% WHLR containing serum group, the vehicle serum control group. MPCs in the normal control group were cultured at 37 degrees C culture solution for 24 h. 45 mg/L puromycin was acted on MPCs in the model group for 24 h. On the basis of puromycin intervention, 1 limol/L DEX was co-incubated in MPCs of the DEX group for 24 h; 10% or 20% WHLR containing serum was co-incubated in MPCs of the 10% WHLR containing serum group and 20% WHLR containing serum group for 24 h. The vehicle serum control group was also set up by incubating with WHLR containing serum alone for 24 h. The expression of CatL and its substrate Synaptopodin in podocytes were detected by cell immunofluorescence staining. FITC-conjugated phalloidin was used to stain F-actin. A cortical F-actin score index (CFS index) was designed to quantify the degree of cytoskeletal reorganization in cultured podocytes.

RESULTSCompared with the normal control group, the expression of synaptopodin significantly decreased and the expression of CatL significantly-increased in the model group. F-actin arranged in disorder, gradually forming pericellular F-actin ring. CFS index was obviously elevated (P < 0.01). Compared with the model group, the epression of synaptopodin increased, the expression of CatL decreased, and CFS index also decreased in the DEX group, 10% WHLR containing serum group, and 20% WHLR containing serum group (P < 0.05, P < 0.01). Compared with the DEX group, the expression of synaptopodin decreased in 10% WHLR containing serum group, CFS index also decreased in 20% WHLR containing serum group (P < 0.05).

CONCLUSIONSWHLR could up-regulate the expression of synaptopodin, down-regulate the expression of CatL, and alleviate cytoskeletal reorganization of F-actin. It was helpful to stabilize the cytoskeleton of F-actin and improve the merging of podocytes.

Actins ; metabolism ; Animals ; Cathepsin L ; metabolism ; Cells, Cultured ; Down-Regulation ; Drugs, Chinese Herbal ; pharmacology ; Kidney Glomerulus ; cytology ; Mice ; Microfilament Proteins ; metabolism ; Podocytes ; drug effects ; pathology ; Puromycin Aminonucleoside ; adverse effects ; Up-Regulation

OBJECTIVETo investigate RANK-RANKL expression in the kidneys of a rat model of puromycin aminonucleoside nephropathy (PAN).

METHODSThirty-six SD rats were randomly divided into PAN model group and normal control group. PAN was induced by a single intravenous injection of 100 mg/kg puromycin aminonucleoside. Serum creatinine and 24-hour urinary protein were measured on days 3, 7, and 14 after the injection, and renal pathologies were assessed with optical and immune transmission electron microscopy. The expression of RANK and RANKL in the kidneys was examined using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting.

RESULTSThe PAN model rats showed massive proteinuria and elevated serum creatinine on day 3, which peaked on day 7. RANK-RANKL protein and mRNA expressions in PAN model group was higher than those in the control group. In the PAN rats, RANK was expressed mainly on the top cell membrane and in the cytoplasm of renal podocytes with a significantly increased expression level compared with that in the control group.

CONCLUSIONThe PAN rat model shows aberrant RANK and RANKL expressions in the podocytes, indicating their contribution to podocyte injury in PAN.

Animals ; Creatinine ; blood ; Female ; Kidney ; drug effects ; metabolism ; Kidney Diseases ; chemically induced ; metabolism ; pathology ; Male ; Podocytes ; drug effects ; metabolism ; Proteinuria ; pathology ; Puromycin Aminonucleoside ; adverse effects ; RANK Ligand ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptor Activator of Nuclear Factor-kappa B ; metabolism

PURPOSE: To test whether the expression of P-cadherin, a component of slit diaphragms between podocyte foot processes, would be altered by puromycin aminonucleoside (PAN) in a cultured podocyte in vitro. METHODS: Rat glomerular epithelial cells (GEpC) were cultured with various concentrations of PAN. The distribution of P-cadherin was examined with a confocal microscope. Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR) were used to measure the change in P-cadherin expression. RESULTS: This study found that P-cadherin was concentrated in the inner and peripheral cytoplasm with high concentrations of PAN under immunofluorescence views. Western blotting of GEpC revealed that PAN induced a decrease of P-cadherin in dose- and time-dependent manners. A high dose (50 microg/mL) of PAN decreased P-cadherin expression by 21.9% at 24 h (P<0.05) and 31.9% at 48 h (P<0.01) compared to those without PAN. In RT-PCR, high concentrations (50 microg/mL) of PAN also decreased P-cadherin mRNA expression, similar to protein suppression, by 23.5% at 48 h (P<0.05). CONCLUSION: Podocytes exposed to PAN in vitro concentrated P-cadherin internally, and reduced P-cadherin mRNA and protein expression. This could explain the development of proteinuria in experimental PAN-induced nephropathy.
Animals ; Ascorbic Acid ; Blotting, Western ; Cadherins* ; Cytoplasm ; Diaphragm ; Epithelial Cells ; Fluorescent Antibody Technique ; Foot ; Glycyrrhetinic Acid ; Podocytes* ; Proteinuria ; Puromycin Aminonucleoside* ; Puromycin* ; Rats ; RNA, Messenger

OBJECTIVETo observe the differential expression characteristics of microRNAs (miRNAs) in renal tissues in puromycin aminonucleoside (PAN) nephritic model, and its relationship with key structural molecules of slid diaphragm (SD) nephrin and podocin and expression of skeleton protein synaptopodin; and to explore the in vivo mechanisms of Leizhi capsule (LZC) for ameliorating the expressions of nephrin, podocin and synaptopodin and reducing proteins by regulating the modal rat renal tissues miRNAs.

METHODFifty male Wistar rats were randomly divided into five groups: the control group (A), the model group (B), the LZC-treated group (C), the multi-glycoside of Tripterygium wilfordii (GTW)-treated group (D) and the valsartan-treated group (E). Apart from group A, all of rats in the remaining groups are injected with PAN (100 mg x kg(-1)) through jugular veins to establish the PAN nephropathy model. On the 2nd day after PAN nephropathy model was established, group C was orally administered with LZC (5 mL x kg(-1) x d(-1)) in group C, group DGTW (10 mL x kg(-1) x d(-1)), and E group valsartan (7.5 mL x kg(-1) x d(-1)), while groups A and B were intervened with physiological saline, for 10 days. Body weight and 24 h urinary protein ration (Upro) in all rats were measured at day 0, 3, and 9. All rats were sacrificed at day 11 after the establishment of the model, and their blood and renal tissues were collected to observe such blood biochemical indicators including albumin (Alb), serum creatinine (Scr), blood urea nitrogen (BUN) and glomerular ultrastructure (podocyte foot process form) and expressions of dicer enzyme, nephrin, podocin and synaptopodin in renal tissues. Meanwhile, the differential expressional characteristics of miRNAs in renal cortex were analyzed by biochip assay. Additionally, the differential expressional volumes of rno-miR-23a, rno-miR-300-3p, rno-miR-24 and rno-miR-30c were measured by real-time PCR.

RESULTProteinuria, renal dysfunction, hypoproteinemia and podocyte foot process fusion were investigated in model rats induced by PAN. In renal tissues of PAN nephropathy model rats, dicer enzyme affected the expressions of nephrin, podocin and synaptopodin in podocytes, up-regulated the expressions of rno-miR-23a and rno-miR-300-3p, and down-regulated the expressions of rno-miR-24 and rno-miR-30c. The miRNAs with differential expressions included rno-miR-24, rno-miR-30c, rno-miR-23a and rno-miR-300-3p. LZC could improve the general state, proteinuria, serum BUN and podocyte foot process fusion of PAN nephropathy model rats, reduced the expressions of dicer enzyme, increased the expressions of nephrin, podocin and synaptopodin in podocytes, weakened the up-regulated rno-miR-23a and rno-miR-300-3p, and strengthened the down-regulated rno-miR-24 and rno-miR-30c in renal tissues.

CONCLUSIONPAN in vivo impacts the expressions of miRNAs in renal tissues, intervenes the expressions of nephrin, podocin and synaptopodin in podocytes, damages podocyte structures and functions and generates proteinuria by means of differential expression of dicer enayme/miRNAs. LZC can reduce proteinuria in PAN nephropathy model rats. Its mechanism may intervene dicer enayme/miRNAs differential expression, regulate nephrin, podocin and synaptopodin in podocytes and improve podocyte structures and functions.

Animals ; Drugs, Chinese Herbal ; administration & dosage ; Gene Expression ; drug effects ; Humans ; Kidney Diseases ; chemically induced ; drug therapy ; genetics ; metabolism ; Male ; MicroRNAs ; genetics ; metabolism ; Puromycin Aminonucleoside ; adverse effects ; Rats ; Rats, Wistar

PURPOSE: Puromycin aminonucleoside (PAN) specifically injures podocytes, leading to foot process effacement, actin cytoskeleton disorganization, and abnormal distribution of slit diaphragm proteins. p130Cas is a docking protein connecting F-actin fibers to the glomerular basement membrane (GBM) and adapter proteins in glomerular epithelial cells (GEpCs; podocytes). We investigated the changes in the p130Cas expression level in the PAN-induced pathological changes of podocytes in vitro. METHODS: We observed changes in the p130Cas expression in cultured rat GEpCs and mouse podocytes treated with various concentrations of PAN and antioxidants, including probucol, epigallocatechin gallate (EGCG), and vitamin C. The changes in the p130Cas expression level were analyzed using confocal immunofluorescence imaging, Western blotting, and polymerase chain reaction. RESULTS: In the immunofluorescence study, p130Cas showed a diffuse cytoplasmic distribution with accumulation at distinct sites visible as short stripes and colocalized with P-cadherin. The fluorescences of the p130Cas protein were internalized and became granular by PAN administration in a dose-dependent manner, which had been restored by antioxidants, EGCG and vitamin C. PAN also decreased the protein and mRNA expression levels of p130Cas at high doses and in a longer exposed duration, which had been also reversed by antioxidants. CONCLUSION: These findings suggest that PAN modulates the quantitative and distributional changes of podocyte p130Cas through oxidative stress resulting in podocyte dysfunction.
Actin Cytoskeleton ; Actins ; Animals ; Antioxidants ; Ascorbic Acid ; Blotting, Western ; Cadherins ; Catechin ; Crk-Associated Substrate Protein ; Cytoplasm ; Cytoskeleton ; Diaphragm ; Epithelial Cells ; Fluorescent Antibody Technique ; Foot ; Glomerular Basement Membrane ; Mice ; Oxidative Stress ; Podocytes ; Probucol ; Proteins ; Puromycin ; Puromycin Aminonucleoside ; Rats ; RNA, Messenger

This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA (shRNA) targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside (PAN)-induced podocyte injury. Two DNA sequences containing the small hairpin structure targeting TRPC6 were designed, synthesized and then inserted into the green fluorescence protein (GFP)-contained plasmids (pGC) to establish the plasmids pGCsi-TRPC6A and pGCsi-TRPC6B. Plasmids expressing scrambled shRNA were used as negative control and named pGCsi-NC. These plasmids were transfected into a conditionally immortalized murine podocyte cell line by using liposome. Flow cytometry was used to examine the transfection efficiency. TRPC6 mRNA and protein expression levels were detected by RT-PCR and Western blotting. Cultured podocytes were divided into four groups: control group, PAN treatment group, PAN+TRPC6 shRNA transfected group and PAN+scrambled shRNA transfected group. The paracelluar permeability to BSA was evaluated by Millicell-PCF Inserts and cell viability was measured by the trypan blue assay. Immunofluorescent assay was used to observe the distribution of α-actinin-4 and α-tubulin. The results showed that the transfection efficiency of the shRNA expression vector was about 45%. Expression levels of TRPC6 mRNA and protein were downregulated after transfection with pGCsi-TRPC6A and pGCsi-TRPC6B. Knocking down TRPC6 gene could effectively reverse the PAN-induced increase in the paracelluar permeability to BSA. The distribution of α-actinin-4 and α-tubulin was disrupted after treatment with PAN, which was reversed by knocking down TRPC6 gene. It was concluded that knocking down TRPC6 gene could effectively prevent podocytes from the permeability increase induced by PAN, which may be related to the regulation of podocyte cytoskeleton.
Animals ; Cell Membrane Permeability ; drug effects ; physiology ; Cell Survival ; drug effects ; physiology ; Cells, Cultured ; Gene Knockdown Techniques ; Mice ; Mice, Knockout ; Podocytes ; drug effects ; physiology ; Puromycin Aminonucleoside ; pharmacology ; TRPC Cation Channels ; genetics ; metabolism

Proteinuria is a major promoter that induces tubulointerstitial injury in glomerulopathy. Dietary salt restriction may reduce proteinuria, although the mechanism is not clear. We investigated the effects of dietary salt restriction on rat kidneys in an animal model of glomerular proteinuria. Male Sprague-Dawley rats were used and divided into 3 groups: vehicle-treated normal-salt controls, puromycin aminonucleoside (PA)-treated normal-salt rats, and PA-treated low-salt rats. PA was given at a dose of 150 mg/kg BW at time 0, followed by 50 mg/kg BW on days 28, 35, and 42. Sodium-deficient rodent diet with and without additional NaCl (0.5%) were provided for normal-salt rats and low-salt rats, respectively. On day 63, kidneys were harvested for histopathologic examination and immunohistochemistry. PA treatment produced overt proteinuria and renal damage. Dietary salt restriction insignificantly reduced proteinuria in PA-treated rats, and PA-treated low-salt rats had lower urine output and lower creatinine clearance than vehicle-treated normal-salt controls. When tubulointerstitial injury was semiquantitatively evaluated, it had a positive correlation with proteinuria. The tubulointerstitial injury score was significantly increased by PA treatment and relieved by low-salt diet. ED1-positive infiltrating cells and immunostaining for interstitial collagen III were significantly increased by PA treatment. These changes appeared to be less common in PA-treated low-salt rats, although the differences in PA-treated normal-salt versus low-salt rats did not reach statistical significance. Our results suggest that renal histopathology in PA nephrosis may potentially be improved by dietary salt restriction. Non-hemodynamic mechanisms induced by low-sodium diet might contribute to renoprotection.
Animals ; Collagen ; Creatinine ; Diet ; Diet, Sodium-Restricted ; Humans ; Immunohistochemistry ; Kidney ; Male ; Models, Animal ; Nephrosis ; Proteinuria ; Puromycin ; Puromycin Aminonucleoside ; Rats ; Rats, Sprague-Dawley ; Rodentia