No abstract available.
Animals ; DNA* ; LLC-PK1 Cells* ; Swine

Four flavonoids were isolated from Gynostemma pentaphyllum by chromatography methods and their structures were identified by MS and NMR spectra data as quercetin-3-O-( 2″,6″-di-α-L-rhamnosyl)-β-D-galactopyranoside( 1),quercetin-3-O-( 2″,6″-di-α-L-rhamnosyl)-β-D-glucopyranoside( 2),quercetin-3-O-( 2″-α-L-rhamnosyl)-β-D-galactopyranoside( 3),and quercetin-3-O-( 2″-α-L-rhamnosyl)-β-D-glucopyranoside( 4). Among them,compounds 1-3 were obtained from the Cucurbitaceae family for the first time.The four flavonoids showed potent antioxidant effects against the DPPH,·OH and ■radicals in vitro,especially for DPPH radical scavenging activity with the IC50 values of 71. 4,29. 5,48. 3 and 79. 2 μmol·L~(-1),respectively. Moreover,the four flavonoids displayed strong cytoprotection against AAPH-induced oxidative damage in LLC-PK1 cells by suppressing the increase of malondialdehyde( MDA) and the decrease of the superoxide dismutase( SOD) and glutathione( GSH). Since further research is needed to prove its efficacy in vivo and clinical trial,the study may provide four potential antioxidants from G. pentaphyllum.
Animals ; Antioxidants ; Flavonoids ; Gynostemma ; LLC-PK1 Cells ; Oxidative Stress ; Plant Extracts ; Quercetin ; Swine

Cis-dichlorodiammine platinum II (Cisplatin), an effective chemotherapeutic agent, induces acute renal failure by unknown mechanisms. To investigate direct toxic effects of cisplatin on the renal proximal tubular transport system, LLC-PK-1 cell line was selected as a cell model and the sugar transport activity was evaluated during a course of cisplatin treatment. Cells grown to confluence were treated with cisplatin for 60 min, washed, and then incubated for up to 5 days. At appropriate intervals, cells were tested for sugar transport activity using alpha-methyl-D-(14C)glucopyranoside (AMG) as a model substrate. In cells treated with 100 micrometer cisplatin, the AMG uptake was progressively impaired after 3 days. The viability of cells was not substantially changed with cisplatin of less than 100 micrometer, but it decreased markedly with 150 and 200 micrometer. In cisplatin-treated cells, the Na+/-dependent AMG uptake was drastically inhibited with no change in the Na+/-independent uptake. Kinetic analysis indicated that Vmax was suppressed, but Km was not altered. The Na+/-dependent phlorizin binding was also decreased in cisplatin-treated cells. However, the AMG efflux from preloaded cells was not apparently retarded by cisplatin treatment. These data indicate that the cisplatin treatment impairs Na+/-hexose cotransporters in LLC-PK-1 cells and suggest strongly that defects in transporter function at the luminal plasma membrane of the proximal tubular cells constitute an important pathogenic mechanism of cisplatin nephrotoxicity.
Acute Kidney Injury ; Animals ; Cell Line ; Cell Membrane ; Cisplatin* ; Epithelial Cells* ; LLC-PK1 Cells ; Phenobarbital ; Phlorhizin ; Platinum ; Swine

OBJECTIVETo sift and identify the nephrotoxic components in Zexie for controlling the quality of the herb.

METHODThe fractions of zexie were prepared by Pre-HPLC, then the nephrotoxicity of the fraction was sifted using LLC-PK1 labelled with fluorescein diacetate and MTT assay. Finally, the compounds in the most obvious nephrotoxic fraction were identified with LC-MS.

RESULTUsing MTT and FDA assay, similar results were obtained. Fraction C13 was found to be the most toxic with FDA assay, in which three compounds, alisol C, 16, 23-oxido-alisol B and alisol O, were detected and characterized by multi -stage mass spectrometric analysis.

CONCLUSIONAlisol C, 16, 23-oxido-alisol B and alisol O in Zexie may cause nephrotoxicity.

Alisma ; chemistry ; toxicity ; Animals ; Chromatography, High Pressure Liquid ; Kidney ; drug effects ; LLC-PK1 Cells ; Mass Spectrometry ; Swine

Renal impairment is one of frequent and serious complications in patients with multiple myeloma (MM) and is associated with a higher incidence of infections and early death rate. The catalytic activity of Bence Jones proteins (BJP) affects the clinical processes of patients with MM, and can lead to renal impairment. Scientists point out that BJP have peptidolytic and nucleolytic activity, which can lead porcine kidney proximal tubule (LLC-PK1) to apoptosis in vitro experiments. By treating the cytotoxic BJP with serine protease inhibitor (DFP), BJP lost not only their catalytic activity, but also the cytotoxic effects. Therefore, further research on BJP will helpful to understand the pathogenesis of renal impairment in MM patients and may provide a new idea and measure for the treatment of MM with renal impairment. This article reviews the basic research and progress on the catalytic activity of BJP.
Animals ; Apoptosis ; Bence Jones Protein ; metabolism ; Humans ; Kidney ; pathology ; LLC-PK1 Cells ; Multiple Myeloma ; metabolism ; pathology ; Swine

This study was purposed to investigate the relationship between the catalysis of Bence Jones protein (BJP) in urine of patients with multiple myeloma(MM) and toxicity on the renal proximal tubular cells in vitro, and to explore the potential mechanism for the toxicity of BJP to renal impairment in patients with MM. The Michaelis-Menten constant (K(m)) and catalytic constant (k(cat)) of the amidase activity of BJP was calculated by Hanes equation. The LLC-PK1 cells were cultured with different concentration of BJP for 24 h, then proliferation of the cells were determined by MTT method and apoptosis were determined by flow cytometry. The results showed that the BJP from the MM patients with renal impairment significantly inhibited cell proliferation, as compared with that from MM patients without renal impairment. The BJP with higher k(cat) had higher toxicity to LLC-PK1 cells. BJP could induce apoptosis and necrosis of LLC-PK1 cells when reached a certain concentration and this effect enhanced with increase of BJP concentration. It is concluded that the catalysis of BJP and its toxicity to renal tubular epithelial cells has a positive correlation, and toxic effect of BJP on renal tubular epithelial cells results from inhibiting proliferation and inducing apoptosis and necrosis of the cells, which may be one of renal impairment mechanisms in MM patients.
Animals ; Bence Jones Protein ; metabolism ; toxicity ; Catalysis ; Coculture Techniques ; Epithelial Cells ; metabolism ; pathology ; Humans ; Kidney ; metabolism ; pathology ; Kidney Tubules ; cytology ; LLC-PK1 Cells ; Multiple Myeloma ; metabolism ; pathology ; Swine

BACKGROUND/OBJECTIVES: This study was performed to investigate the in vitro antioxidant and cytoprotective effects of fermented sesame sauce (FSeS) against hydrogen peroxide (H2O2)-induced oxidative damage in renal proximal tubule LLC-PK1 cells. MATERIALS/METHODS: 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical (*OH), and H2O2 scavenging assay was used to evaluate the in vitro antioxidant activity of FSeS. To investigate the cytoprotective effect of FSeS against H2O2-induced oxidative damage in LLC-PK1 cells, the cellular levels of reactive oxygen species (ROS), lipid peroxidation, and endogenous antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-px) were measured. RESULTS: The ability of FSeS to scavenge DPPH, *OH and H2O2 was greater than that of FSS and AHSS. FSeS also significantly inhibited H2O2-induced (500 microM) oxidative damage in the LLC-PK1 cells compared to FSS and AHSS (P < 0.05). Following treatment with 100 microg/mL of FSeS and FSS to prevent H2O2-induced oxidation, cell viability increased from 56.7% (control) to 83.7% and 75.6%, respectively. However, AHSS was not able to reduce H2O2-induced cell damage (viability of the AHSS-treated cells was 54.6%). FSeS more effectively suppressed H2O2-induced ROS generation and lipid peroxidation compared to FSS and AHSS (P < 0.05). Compared to the other sauces, FSeS also significantly increased cellular CAT, SOD, and GSH-px activities and mRNA expression (P < 0.05). CONCULUSIONS: These results from the present study suggest that FSeS is an effective radical scavenger and protects against H2O2-induced oxidative damage in LLC-PK1 cells by reducing ROS levels, inhibiting lipid peroxidation, and stimulating antioxidant enzyme activity.
Animals ; Catalase ; Cats ; Cell Survival ; Glutathione Peroxidase ; Hydrogen Peroxide ; Hydrogen* ; Hydroxyl Radical ; Lipid Peroxidation ; LLC-PK1 Cells ; Oxidative Stress ; Reactive Oxygen Species ; RNA, Messenger ; Sesamum* ; Superoxide Dismutase ; Swine

This study aimed to investigate the in vivo relevance of P-glycoprotein (P-gp) in the pharmacokinetics and adverse effect of phenformin. To investigate the involvement of P-gp in the transport of phenformin, a bi-directional transport of phenformin was carried out in LLC-PK1 cells overexpressing P-gp, LLC-PK1-Pgp. Basal to apical transport of phenformin was 3.9-fold greater than apical to basal transport and became saturated with increasing phenformin concentration (2-75 µM) in LLC-PK1-Pgp, suggesting the involvement of P-gp in phenformin transport. Intrinsic clearance mediated by P-gp was 1.9 µL/min while passive diffusion clearance was 0.31 µL/min. Thus, P-gp contributed more to phenformin transport than passive diffusion. To investigate the contribution of P-gp on the pharmacokinetics and adverse effect of phenformin, the effects of verapamil, a P-gp inhibitor, on the pharmacokinetics of phenformin were also examined in rats. The plasma concentrations of phenformin were increased following oral administration of phenformin and intravenous verapamil infusion compared with those administerd phenformin alone. Pharmacokinetic parameters such as Cmax and AUC of phenformin increased and CL/F and Vss/F decreased as a consequence of verapamil treatment. These results suggested that P-gp blockade by verapamil may decrease the phenformin disposition and increase plasma phenformin concentrations. P-gp inhibition by verapamil treatment also increased plasma lactate concentration, which is a crucial adverse event of phenformin. In conclusion, P-gp may play an important role in phenformin transport process and, therefore, contribute to the modulation of pharmacokinetics of phenformin and onset of plasma lactate level.
Administration, Oral ; Animals ; Area Under Curve ; Diffusion ; Intestinal Absorption ; Lactic Acid* ; LLC-PK1 Cells ; P-Glycoprotein* ; Pharmacokinetics ; Phenformin* ; Plasma* ; Rats ; Swine ; Verapamil

OBJECTIVETo study the cytotoxicity of maitotoxin (MTX) and its protective effects on calcium-channel blocking agents, so as to provide the data for control and treatment of MTX poisoning.

METHODSCytotoxicity was measured by MTT detecting system, and cytoplasmic free [Ca(2+)]i was measured by F-4500 fluorometry.

RESULTSIncubation with 8 ng/ml MTX for 3 h reduced the survival ratio of LLC-PK(1) cells. The response was found in a time- and concentration-dependent manner, with significant differences as compared with the control group. The MTX-induced increase in [Ca(2+)]i was inhibited by Verapamil and Nifedipine at 5 x 10(-5) mol/L and 1 x 10(-4) mol/L respectively. Both of them significantly reduced the death of the LLC-PK(1) cells.

CONCLUSIONSCytotoxicity of MTX may be caused by the elevated intracellular [Ca(2+)]i. Calcium-channel blocking agents could protect LLC-PK(1) cells from injury by MTX.

Animals ; Calcium ; metabolism ; Calcium Channel Blockers ; pharmacology ; Drug Antagonism ; LLC-PK1 Cells ; Marine Toxins ; toxicity ; Nifedipine ; pharmacology ; Oxocins ; Swine ; Verapamil ; pharmacology

BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a prototype compound of polyhalogenated aromatic hydrocarbons, produces diverse biologic effects. Although nephrotoxicity of aromatic hydrocarbons such as benzo[a]pyrene(BP) is well known, little is known about the effects of TCDD on renal function. Thus, the present study examined the effects of TCDD on cell viability, proliferation, and extracellular matrix(ECM) synthesis by glomerular mesangial cells, LLC-PK1 cells representing proximal tubular epithelial cells, and MDCK cells representing distal epithelial cells and compared with the effects of BP. METHODS: Quiescent cells were incubated with serum free media containing different concentrations of TCDD(1-100 nM) and BP(3 and 30 micro M) for 24- 96 hours. Cell viability and proliferation were assessed by lactate dehydrogenase(LDH) release and [3H]-thymidine incorporation, respectively. Secreted fibronectin was measured by Western blot analysis. RESULTS: When cells were continuously exposed to TCDD, LDH release significantly increased in MMC, LLC-PK1, and MDCK in a dose- and a time- dependent manner. [3H]-Thymidine incorporation was increased in MMC and LLC-PK1 but decreased in MDCK by TCDD. Contrary to TCDD, 30 micro BP significantly inhibited [3H]-thymidine incorporation in MMC and MDCK but not in LLC-PK1. Both TCDD and BP increased fibronectin secretion by MMC, LLC-PK1, and MDCK cells, suggesting that TCDD and BP may cause renal fibrosis leading to loss of renal function. CONCLUSION: These data provide experimental evidence that TCDD can alter cell viability and proliferation and increase ECM synthesis by renal cells which may lead to renal injury.
Animals ; Blotting, Western ; Cell Survival ; Culture Media, Serum-Free ; Epithelial Cells* ; Fibronectins ; Fibrosis ; Hydrocarbons, Aromatic ; Lactic Acid ; LLC-PK1 Cells ; Madin Darby Canine Kidney Cells ; Mesangial Cells ; Swine ; Tetrachlorodibenzodioxin