OBJECTIVE: To investigate the protective effects of stir-fried Semen Armeniacae Amarum (SAA) against aristolochic acid I (AAI)-induced nephrotoxicity and DNA adducts and elucidate the underlying mechanism involved for ensuring the safe use of Asari Radix et Rhizoma. METHODS: In vitro, HEK293T cells overexpressing Flag-tagged multidrug resistance-associated protein 3 (MRP3) were constructed by Lentiviral transduction, and inhibitory effect of top 10 common pairs of medicinal herbs with Asari Radix et Rhizoma in clinic on MRP3 activity was verified using a self-constructed fluorescence screening system. The mRNA, protein expressions, and enzyme activity levels of NAD(P)H quinone dehydrogenase 1 (NQO1) and cytochrome P450 1A2 (CYP1A2) were measured in differentiated HepaRG cells. Hepatocyte toxicity after inhibition of AAI metabolite transport was detected using cell counting kit-8 assay. In vivo, C57BL/6 mice were randomly divided into 5 groups according to a random number table, including: control (1% sodium bicarbonate), AAI (10 mg/kg), stir-fried SAA (1.75 g/kg) and AAI + stir-fried SAA (1.75 and 8.75 g/kg) groups, 6 mice in each group. After 7 days of continuous gavage administration, liver and kidney damages were assessed, and the protein expressions and enzyme activity of liver metabolic enzymes NQO1 and CYP1A2 were determined simultaneously. RESULTS: In vivo, combination of 1.75 g/kg SAA and 10 mg/kg AAI suppressed AAI-induced nephrotoxicity and reduced dA-ALI formation by 26.7%, and these detoxification effects in a dose-dependent manner (P<0.01). Mechanistically, SAA inhibited MRP3 transport in vitro, downregulated NQO1 expression in vivo, increased CYP1A2 expression and enzymatic activity in vitro and in vivo, respectively (P<0.05 or P<0.01). Notably, SAA also reduced AAI-induced hepatotoxicity throughout the detoxification process, as indicated by a 41.3% reduction in the number of liver adducts (P<0.01). CONCLUSIONS Stir-fried SAA is a novel drug candidate for the suppression of AAI-induced liver and kidney damages. The protective mechanism may be closely related to the regulation of transporters and metabolic enzymes.
Aristolochic Acids/toxicity* ; Animals ; Humans ; NAD(P)H Dehydrogenase (Quinone)/genetics* ; HEK293 Cells ; Kidney/pathology* ; Cytochrome P-450 CYP1A2/genetics* ; Mice, Inbred C57BL ; DNA Adducts/drug effects* ; Male ; Kidney Diseases/drug therapy* ; Drugs, Chinese Herbal/therapeutic use* ; Mice ; Prunus armeniaca ; Plant Extracts

OBJECTIVE: To investigate the protective effects of Schisandra chinensis oil (SCEO) against aristolochic acid I (AA I)-induced nephrotoxicity in vivo and in vitro and elucidate the underlying mechanism. METHODS: C57BL/6 mice were randomly divided into 5 groups according to a random number table, including control group, AA I group, and AA I +SCEO (0.25, 0.5 and 1 g/kg) groups (n=5 per group). Pretreatment with SCEO was done for 2 days by oral administration, while the control and AA I groups were treated with sodium carboxymethyl cellulose. Mice of all groups except for the control group were injected intraperitoneally with AA I (5 mg/kg) from day 3 until day 7. Histopathological examination and apoptosis of kidney tissue were observed by hematoxylin and eosin and TdT-mediated dUTP nick-end labeling (TUNEL) staining, respectively. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and serum creatinine (SCr), as well as renal malondialdehyde (MDA), glutathione, r-glutamyl cysteingl+glycine (GSH), and superoxide dismutase (SOD) were analyzed using enzyme-linked immunosorbent assay (ELISA). Expressions of hepatic cytochrome P450 1A1 (CYP1A1), CYP1A2, and nad(p)hquinonedehydrogenase1 (NQO1) were analyzed using ELISA, quantitative real-time polymerase chain reaction (qPCR) and Western blot, respectively. In vitro, SCEO (40 µ g/mL) was added 12 h before treatment with AA I (40 µ mol/mL for 48 h) in human renal proximal tubule cell line (HK-2), then apoptosis and reactive oxygen species (ROS) were analyzed by flow cytometry. RESULTS: SCEO 0.5 and 1 g/kg ameliorated histopathological changes and TUNEL⁺ staining in the kidney tissues of mice with AA I-induced nephrotoxicity, and reduced serum levels of ALT, AST, BUN and SCr (P<0.01 or P<0.05). SCEO 0.5 and 1 g/kg alleviated the ROS generation in kidney, containing MDA, GSH and SOD (P<0.01 or P<0.05). SCEO 1 g/kg increased the expressions of CYP1A1 and CYP1A2 and decreased NQO1 level in the liver tissues (P<0.01 or P<0.05). Besides, in vitro studies also demonstrated that SCEO 40 µ g/mL inhibited apoptosis and ROS generation (P<0.05 or P<0.01). CONCLUSIONS SCEO can alleviate AA I-induced kidney damage both in vivo and in vitro. The protective mechanism may be closely related to the regulation of metabolic enzymes, thereby inhibiting apoptosis and ROS production.
Animals ; Apoptosis ; Aristolochic Acids/toxicity* ; Cytochrome P-450 CYP1A1/metabolism* ; Cytochrome P-450 CYP1A2/metabolism* ; Glutathione/metabolism* ; Kidney/drug effects* ; Kidney Diseases/drug therapy* ; Mice ; Mice, Inbred C57BL ; Oxidative Stress ; Plant Oils/therapeutic use* ; Protective Agents/therapeutic use* ; Reactive Oxygen Species/metabolism* ; Schisandra ; Superoxide Dismutase/metabolism*

Recently, Ng et al. reported that the A:T > T:A substitutions, proposed to be a signature of aristolochic acid (AA) exposure, were detected in 76/98 (78%) of patients with hepatocellular carcinoma (HCC) from the Taiwan Province of China, and 47% to 1.7% of HCCs from the Chinese mainland and other countries harbored the nucleotide changes. However, other carcinogens, e.g., tobacco carcinogens 4-aminobiphenyl and 1,3-butadiene, air toxic vinyl chloride and its reactive metabolites chloroethylene oxide, melphalan and chlorambucil, also cause this signature in the genome. Since tobacco smoke is a worldwide public health threat and vinyl chloride distributes globally and is an air pollutant in Taiwan Province, the estimation of the patients' exposure history is the key to determine the "culprit" of the A:T > T:A mutations. Apparently, without estimation of the patients' exposure history, the conclusion of Ng et al. is unpersuasive and misleading.
Aristolochic Acids ; toxicity ; Carcinogens ; toxicity ; Carcinoma, Hepatocellular ; chemically induced ; genetics ; China ; Environment ; Humans ; Liver Neoplasms ; chemically induced ; genetics ; Mutation ; Taiwan ; Tobacco ; toxicity ; Vinyl Chloride ; toxicity

The renal toxicity and mutagenicity of aristolochic acid (AA) as well as its carcinogenicity on upper urinary tract transitional epithelial cells have been widely known. Since 2003, drug regulatory departments have successively cancelled the quality standards for AA-containing medicines such as Aristolochiae Radix, Aristolochiae Manshuriensis Caulis and Aristolchiae Fangchi Radix, and adopted measures for strengthening regulation and revising package insert or quality standards for other AA-containing medicines, including Aristolochia Cinnabarina Radix, Aristolochiae Fructus, Aristolochiae Mollissimae Herba, in order to control its safety risk. In recent years, domestic and foreign studies on AA have mainly involved action mechanism and clinical performance of AA toxicity, early-stage diagnosis and treatment method. In this paper, authors gave a brief summary and evaluation on risk factors for using AA-containing medicines, and offered measures and suggestions for preventing and controlling AA toxicity.
Animals ; Aristolochia ; adverse effects ; chemistry ; Aristolochic Acids ; analysis ; therapeutic use ; toxicity ; Drug Therapy ; Drug-Related Side Effects and Adverse Reactions ; epidemiology ; etiology ; Drugs, Chinese Herbal ; analysis ; therapeutic use ; toxicity ; Humans

OBJECTIVETo investigate the effect of both fermented Cordyceps powder (CS) and prednisone on the Notch2/hes-1 signaling activation in the kidney tubules of rats with acute aristolochic acid nephropathy (AAAN).

METHODSTotally 50 SD rats were randomly divided into 4 groups, i.e., the normal group, the model group, the CS group, the prednisone group, and the CS plus prednisone group, 10 in each group. The AAAN rat model was induced by intragastric administration of pure aristolochic acid A at the daily dose of 100 mg/kg for 3 days. Rats in the CS group were administered with CS at the daily dose of 5.0 g/kg by gastrogavage, while those in the prednisone group were administered with prednisone at the daily dose of 0.5 mg/kg. Rats in the CS plus prednisone group were treated by CS and prednisone. All treatment lasted for 3 successive weeks. Kidney functions [urea nitrogen (BUN) and serum creatinine (SCr)] were detected. The pathological changes of kidneys were observed by Hematoxylin-Eosin staining. The apoptosis of the renal tubular epithelial cells was detected by TUNEL. The protein expressions of Notch2 and Hes-1 in the renal tissue were detected by immunohistochemical assay and Western blot.

RESULTSResults of HE staining showed the structure in the nephridial tissue was regular in rats of the normal group. The renal tubular necrosis occurred in the rats of the model group. The pathological changes of kidneys were obviously improved in the CS group, the prednisone group, and the CS plus prednisone group. Compared with the normal group, levels of BUN and SCr, semi-quantitative score of the tubular interstitial tissue, ratio of apoptotic cells, and expressions of Notch2 and Hes-1 proteins significantly increased in the model group (P < 0.01). Compared with the model group, the aforesaid indices significantly decreased in the 3 treatment groups (P < 0.01). All indices decreased most obviously in the CS plus prednisone group (P < 0.05, P < 0. 01).

CONCLUSIONSNotch2/hes-1 signaling activation might be associated with apoptosis of renal tubular epithelial cells. Both CS and prednisone could play a nephroprotective role for AAAN. But CS plus prednisone could achieve the best effect. Inhabiting the Notch2/hes-1 signaling activation could be its nephroprotective mechanism.

Animals ; Apoptosis ; drug effects ; Aristolochic Acids ; toxicity ; Basic Helix-Loop-Helix Transcription Factors ; metabolism ; Cordyceps ; Female ; Homeodomain Proteins ; metabolism ; Kidney ; metabolism ; Kidney Diseases ; chemically induced ; metabolism ; Kidney Function Tests ; Kidney Tubules ; metabolism ; Male ; Prednisone ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptor, Notch2 ; metabolism ; Signal Transduction ; drug effects ; Transcription Factor HES-1

OBJECTIVETo investigate the distributive path and proliferative rule of marrow mesenchymal stem cells (MSCs) in the rat transplanted via caudal vein from male rat to female rats model of chronic aristolochic acid nephropathy (CAAN).

METHODSCells taken from femoral bone marrow of male Wistar rats were made into single cell suspension, cultured, purified and identified as MSCs. MSCs were transplanted via caudal vein into 50 female Wistar CAAN model rats allocated in the test group, they were killed, 10 rats in a batch, at various time points (6 h, 48 h, 10 d, 30 d and 60 d after transplantation). Besides, 10 rats allocated in the control group were killed on the 30th day after received sham-transplantation. Kidney tissue of all rats was taken for detecting cells originated from the donors by fluorescence in situ hybridization test with FAM-labeled sex determining region of Y chromosome (SRY FISH) probe, and their number in SRY was counted using SRY PCR.

RESULTSMSCs were mainly distributed in the glomerular capillaries at the time points of 6 h and 48 h, but the number of MSCs in glomerular capillaries decreased and those in renal mesenchyma increased at the time points from 10 d to 60 d gradually, then tended to a steady state, meanwhile it showed a stable increasing trend in renal tubule. Cell colony of MSCs could be found in mesenchyma with a slowed down increasing between 30 d to 60 d, but the increasing in tubule was still steady.

CONCLUSIONMSCs originated from the donor can enter the kidney of acceptor and distribute from blood capillary to renal mesenchyma and tubule, and they can long time inhabit there and make propagation.

Animals ; Aristolochic Acids ; toxicity ; Bone Marrow Cells ; cytology ; Cell Proliferation ; Female ; Kidney ; pathology ; Kidney Diseases ; chemically induced ; pathology ; Male ; Mesenchymal Stromal Cells ; cytology ; Rats ; Rats, Wistar

OBJECTIVETo investigate the antagonizing effect of Hirsutella sinensis (HS) on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) and its possible pathogenic mechanism in rats with chronic aristolochic acid nephropathy (CAAN).

METHODSEighteen male Sprague-Dawley rats were equally divided into 3 groups, the model (M) group, the intervention (I) group and the control (C) group. The 24 h urinary protein (UP) in rats was measured before intervention and at the end of the 1st, 4th, 8th, and 12th week, and creatinine clearance rate (CCr) was measured before intervention and at the end of the 12th week respectively. All rats were sacrificed at the end of the 12th week, their kidney was taken for examining the degree of fibrosis in renal interstitial with Masson's stain and determining mRNA and protein expressions of transforming growth factor-beta1 (TGF-beta1), Snail, alpha-smooth muscle actin (alpha-SMA) and cytokeratin in renal tissue by Real-time RT-PCR and immunohistochemistry staining, respectively.

RESULTSCompared with the C group, CCr was significantly lower, while 24 h UP was higher; the relative area of interstitial fibrosis was significantly larger in the M group; besides, the mRNA and protein expressions of TGF-beta1, Snail and alpha-SMA were significantly up-regulated (P < 0.01 or P < 0.05), and those of cytokeratin were significantly down-regulated (P < 0.01) in renal tissue of the M group. While in the I group, all the above-mentioned abnormalities were restored to some extent (P < 0.05) and showed significant difference (all P < 0.05) as compared with those in the M group.

CONCLUSIONHS can downregulate TGF-beta1 and Snail expressions in renal tissue, antagonize TEMT and renal interstitial fibrosis, and improve renal function in CAAN rats.

Actins ; genetics ; metabolism ; Animals ; Aristolochic Acids ; toxicity ; Cell Transdifferentiation ; Chronic Disease ; Cordyceps ; chemistry ; Drugs, Chinese Herbal ; therapeutic use ; Fibroblasts ; drug effects ; Kidney Diseases ; chemically induced ; metabolism ; Kidney Tubules ; pathology ; Male ; Phytotherapy ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Snail Family Transcription Factors ; Transcription Factors ; genetics ; metabolism ; Transforming Growth Factor alpha ; genetics ; metabolism

OBJECTIVETo investigate the effect of cytochrome P450 isozymes on aristolochic acid induced cytotoxicity on renal proximal tubular epithelial cell (cell line HK-2).

METHODHuman renal tubular cells (cell line HK-2), were treated with aristolochic acid (AA) alone or in combination with cytochrome P450 isozymes inhibitors, including alpha-naphthoflavone (CYP450 1A1 and 1 A2 inhibitors), ketoconazole (CYP450 3A4 inhibitor), sodium diethyldithiocarbamate (CYP450 2A6 and 2E1 inhibitors), quinidine (CYP450 2D inhibitor), alpha-lipoic acid (NADPH: P450 reductase inhibitor), sulfaphenazole (CYP450 2C inhibitor) in the presence or absence of liver microsome(S9). The inhibition of cell proliferation rate was studied by MTT assay and the lactate dehydrogenase release rate was determined with continuous monitoring method.

RESULTAA inhibits cell proliferation and promotes the release of LDH over the range of 12.5-100 mg x L(-1), in a dose-dependent manner. Addition of S9 into the culture system reduced AA cytotoxicity, with the cell proliferation inhibition reducing and the release of LDH decreasing (AA + S9 group vs the same concentration of AA alone group, P < 0.05). In the absence of S9, ketoconazole or alpha-naphthoflavone has no obvious effect on AA cytotoxicity, however,under the conditions of adding S9, ketoconazole or alpha-naphthoflavone enhances AA cytotoxicity. Other inhibitors of CYP450 isozymes has no distinct effect on AA cytotoxicity.

CONCLUSIONThe microsomal enzyme of Liver can reduce the AA cytotoxicity, and CYP450 3A, CYP450 1A may be the major cytochrome P450 isozymes which impact AA cytotoxicity.

Animals ; Aristolochic Acids ; toxicity ; Cell Line ; Cell Proliferation ; drug effects ; Cytochrome P-450 Enzyme Inhibitors ; Cytochrome P-450 Enzyme System ; metabolism ; Cytotoxicity, Immunologic ; drug effects ; Enzyme Inhibitors ; pharmacology ; Humans ; Kidney Tubules ; drug effects ; enzymology ; immunology ; Male ; Rats ; Rats, Wistar

OBJECTIVETo study whether aristololactam I (AL-I) can enter renal proximal tubular epithelial cells and the situation of intracellular distribution and accumulation.

METHODCultured human renal proximal tubular epithelial cell line (HK-2) was used as the subject. Intracellular fluorescence from AL-I and its distribution are examined by fluorescence microscopy after a treatment with different concentration of AL-I, the intracellular accumulation of AL-I was also investigated by incubated cells in AL-I -free medium for 48 h after washing-out the media containing AL-I.

RESULTAfter treatment of AL-I (concentration from 5 microg x mL(-1) to 20 microg x mL(-1)), glaucous fluorescence could be observed inside renal proximal tubular epithelial cells at 0.5 h, and the fluorescence distributed only in cytoplasm while not be observed in nuclei. Moreover, the fluorescence of AL-I could be kept in cytoplasm for more than 48 h after washing out the media containing AL-I .

CONCLUSIONAL-I is able to enter renal proximal tubular epithelial cells in short time and accumulate in cytoplasm, but not enter nuclei. This property may contribute to the cytotoxic mechanism of renal injury induced by AL-I, which may partially explain the persistent renal toxicity of AAs and its metabolites in the development of aristolochic acid nephropathy.

Animals ; Aristolochic Acids ; metabolism ; toxicity ; Cell Line ; Cell Nucleus ; drug effects ; metabolism ; Cytoplasm ; drug effects ; metabolism ; Epithelial Cells ; cytology ; drug effects ; metabolism ; pathology ; Humans ; Kidney Diseases ; metabolism ; pathology ; Kidney Tubules, Proximal ; cytology ; pathology ; Microscopy, Fluorescence

OBJECTIVETo investigate the relationship between renal tubular cells transdifferentiation and chronic renal interstitial fibrosis induced by Fangchi Extract in rat.

METHODThe chronic renal interstitial fibrosis rat model was made by giving Radix Aristolochiae Fangchi extract (RAFE) and aristolichic acid (AA) respectively to rats through infusing stomach about 22 weeks discontinuously. Through immunnal histochemistry methods, investigating the expression of symbol proteins: Cytokine( CK) , alpha-Smooth muscle actin ( alpha-SMA) and Vimentin, and also the important fibrosis inducing factor-Transforming growth factor-beta (TGF-beta1 )on renal tubular cells.

RESULTIn RAFE and AA Groups, the expression of CK on renal tubular cells is declined comparing with the Control Group, and the enhanced expression of alpha-SMA and Vimentin can be observed on tubular cells. The expression of TGF-beta1 on renal tubular cells stronglhy increased, too.

CONCLUSIONPart of the renal tubular cells was transdifferentiated into myofibroblasts. Renal tubular cells may participate the occurance of chronic renal interstitial fibrosis, TGF-beta1 may accelerate the transdifferentiation of tubular cells.

Actins ; metabolism ; Animals ; Aristolochia ; chemistry ; Aristolochic Acids ; isolation & purification ; toxicity ; Cell Transdifferentiation ; drug effects ; Cytokines ; metabolism ; Drugs, Chinese Herbal ; isolation & purification ; toxicity ; Epithelial Cells ; drug effects ; metabolism ; pathology ; Female ; Fibrosis ; Kidney Diseases ; chemically induced ; metabolism ; physiopathology ; Kidney Tubules ; drug effects ; metabolism ; pathology ; Male ; Plant Extracts ; isolation & purification ; therapeutic use ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; metabolism ; Vimentin ; metabolism