OBJECTIVE: To investigate the role of rebamipide in the treatment of acute gout arthritis rats induced by monosodium urate (MSU) crystal. METHODS: Forty-two male rats were randomly divided into three groups (n=14). Group A was treated with oral rebamipide, group B with oral colchicine, and group C with oral placebo. The rats were monitored for the induction of arthritis with clinical manifestations and pathological changes, and the levels of interleukin (IL)-1β、IL-6、IL-10, and tumor necrosis factor (TNF)-α in serum were measured. RESULTS: In group C, the clinical score and swelling index reached the maximum in 24 h, and then gradually decreased to 72 h. After 24 h of model induced, the clinical scores in group C were significantly higher than those in group A and group B [2 (1-3) vs. 0 (0-1) vs. 1 (0-2), P < 0.01], the swelling indexes in group C were significantly higher than those in group A and group B [0.36 (0.16-0.52) vs. 0.11 (0-0.20) vs. 0.12 (0-0.16), P < 0.01]. Histologically, after 24 h of model induced, there was a large number of neutrophil infiltration in the synovium of group C [scale score: 4 (2-4)], and there was no significant inflammatory cell infiltration in group A [1 (0-2)] and group B [1 (0-2)], the difference was statistically significant (P < 0.001). After 24 h of model induced, the levels of IL-1β, IL-6, IL-10, and TNF-α in serum of group C were significantly higher than those in group A and B [IL-1β: (41.86±5.72) vs. (27.35±7.47) vs. (27.76±5.28) ng/L, IL-6: (1 575.55±167.11) vs. (963.53±90.22) vs. (964.08±99.31) ng/L, IL-10: (37.96±3.76) vs. (21.68±4.83) vs. (16.20±2.49) ng/L, TNF-α: (21.32±1.34) vs. (15.82±2.54) vs. (17.35±7.47) μg/L, P < 0.001]. CONCLUSION Rebamipide has a protective effect on acute gout arthritis rats induced by MUS crystals.
Alanine/analogs & derivatives* ; Animals ; Arthritis, Gouty/drug therapy* ; Interleukin-1beta ; Male ; Quinolones ; Rats ; Uric Acid

OBJECTIVETo establish a method for the determination of theacrine in rat plasma after ig. administration of theacrine.

METHODBlood sample was taken timely from the eyes canthus of rats. Plasma was isolated and the protein was precipitated by ethyl acetate. Then the plasma concentration of theacrine was determined with RP-HPLC. Caffeine was used as the internal standard. The chromatographic conditions were as follows: Phenomenex Luna C18 (4.6 mm x 250 mm, 5 microm) at 25 degrees C, a mixture of methanol-water (25: 75) as the mobile phase, at the flow rate of 1.0 mL x min(-1) and the detection wavelength of 290 nm.

RESULTThe linear range of theacrine was 0.5-100 mg x L(-1) (R2 = 0.998 9). The lower limit of quantification was 0.5 mg x L(-1). The intra-day RSD was 1.49% 4.40% and inter-day RSD was 0.80% -10.27%. The average extraction recoveries of theacrine were 90.3% -95.8% at concentrations of 0.5, 5.0, 50 mg x L(-1). The main pharmacokinetic parameters after ig. administration of theacrine at concentration of 30 mg x kg(-1) were as follow: C(max) (35.45 +/- 30 2.68) mg x L(-1), t(max) (0.51 +/- 0.13) h, t1/2 (3.13 +/- 1.37) h, AUC(0-infinity) (2.65.39 +/- 94.71) mg x L(-1) x h.

CONCLUSIONThe method has been confirmed to be simple, stable, reproducible and with high specificity, and can be used for the pharmacokinetic study of theacrine in rats.

Animals ; Blood Chemical Analysis ; methods ; Calibration ; Chromatography, High Pressure Liquid ; methods ; Chromatography, Reverse-Phase ; methods ; Rats ; Rats, Sprague-Dawley ; Reproducibility of Results ; Uric Acid ; analogs & derivatives ; blood ; pharmacokinetics

AIMTo establish a HPLC method for determining five major metabolites of caffeine in the urine, 5-acetylamino-6-formylamino-3-methyluracil (AFMU), 1-methylxanthine (1X), 1-methyluric acid (1U), 1,7-dimethyluric acid (17U) and 1,7-dimethylxanthine (17X) and assess the activity of cytochrome P-450 CYP2A6.

METHODSThe contents of five major metabolites of caffeine in the urine were determined by RP-HPLC method. Frequency distribution histogram was drawn by calculating the 17U/(AFMU + 1X + 1U + 17X + 17U) and then evaluated the activity of CYP2A6.

RESULTSThe frequency distribution histograms of CYP2A6 approximately indicated three distinct groups, the cut of point is 0.23 between fast metabolizer and intermediate type. And the cut of point is 0.15 between slow metabolizer and intermediate type.

CONCLUSIONThe method is simple and rapid, suitable for the determination of metabolites of caffeine in urine. The method can be used to assay the activity of CYP2A6.

Adult ; Aryl Hydrocarbon Hydroxylases ; metabolism ; Caffeine ; metabolism ; urine ; Chromatography, High Pressure Liquid ; methods ; Cytochrome P-450 CYP2A6 ; Female ; Humans ; Male ; Mixed Function Oxygenases ; metabolism ; Theophylline ; urine ; Uracil ; analogs & derivatives ; urine ; Uric Acid ; analogs & derivatives ; urine ; Xanthines ; urine

To study the metabolite excretion of theophylline, a rapid and specific method by liquid chromatography with heated electrospray ionization tandem mass spectrometry (LC-HESI/MS/MS) method for simultaneous determination of theophylline, 1, 3-dimethyluric acid (1,3-DMU), 3-methylxanthine (3-MX) and 1-methyluric acid (1-MU) in human urine was developed using theophylline-d6 and 5-fluorouracil as internal standards. Selected reaction monitoring (SRM) with heated electrospray ionization (HESI) was used in the negative mode for mass spectrometric detection. After diluted with methanol and centrifuged, the analytes and ISs were separated on a XDB-Phenyl (150 mm x 4.6 mm, 5 microm) column with a mixture of water-methanol-formic acid (30 : 70 : 0.15) as mobile phase at a flow rate of 0.6 mL x min(-1). The linear calibration curves for theophylline, 1, 3-DMU, 3-MX and 1-MU were obtained in the concentration range of 1.0-250 microg x mL(-1), separately. The method herein described is effective and convenient, and can be used for determination of theophylline and its three metabolites. The results showed that urinary excretion ratio of theophylline, 1,3-DMU, 3-MX and 1-MU is approximately 1 : 3 : 1 : 2 in Chinese subjects, which is similar to the reported excretion pattern in Caucasian.
Administration, Oral ; Asian Continental Ancestry Group ; Calibration ; Chromatography, Liquid ; Delayed-Action Preparations ; metabolism ; Healthy Volunteers ; Humans ; Spectrometry, Mass, Electrospray Ionization ; Tablets ; Tandem Mass Spectrometry ; Theophylline ; metabolism ; urine ; Uric Acid ; analogs & derivatives ; urine ; Xanthines ; urine

To study the effect of Tibetan medicine Zuotai on the activity, protein and mRNA expression of CYP1A2 and NAT2, three different doses (1.2, 3.8 and 12 mg x kg(-1)) of Zuotai were administrated orally to rats once a day or once daily for twelve days, separately. Rats were administrated orally caffeine (CF) on the second day after Zuotai administration, and the urine concentration of CF metabolite 5-acetylamino-6-formylamino-3-methyl-uracil (AFMU), 1-methyluric acid (1U), 1-methylxanthine (1X), 1, 7-dimethylxanthine (17U) at 5 h after study drug administration was determined by RP-HPLC. The activity of CYP1A2 and NAT2 was evaluated by the ratio of metabolites (AFMU+1X+1U)/17U and the ratio of AFMU/(AFMU+1X+1U), respectively. The protein and mRNA expression of CYP1A2 and NAT2 were determined by ELISA and RT-PCR method, respectively. After single administration of Zuotai 3.8 mg x kg(-1) and repeated administration of Zuotai 3.8 and 12 mg x kg(-1), the activity of CYP1A2 and NAT2 decreased significantly compared with control group and there was no significant difference between other dose group and control group. The protein expression of CYP1A2 was significant lower than that in control group after repeated administration of Zuotai 12 mg x kg(-1), and the mRNA expression of CYP1A2 decreased significantly compared with that of control group after single administration of Zuotai 3.8 mg x kg(-1) and repeated admistration of Zuotai 12 mg x kg(-1), separately. The protein expression of NAT2 decreased significantly compared with that of control group after single and repeated administration of Zuotai 3.8 mg x kg(-1), respectively, and the mRNA expression of CYP1A2 decreased significantly compared with control group after single administration of Zuotai 3.8 mg x kg(-1). This study found that Tibetan medicine Zuotai had significant effect on the activity, protein and mRNA expression of CYP1A2 and NAT2.
Administration, Oral ; Animals ; Arylamine N-Acetyltransferase ; genetics ; metabolism ; Caffeine ; metabolism ; urine ; Cytochrome P-450 CYP1A2 ; genetics ; metabolism ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Female ; Male ; Medicine, Tibetan Traditional ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Theophylline ; urine ; Uracil ; analogs & derivatives ; urine ; Uric Acid ; analogs & derivatives ; urine ; Xanthines ; urine

Whether nonalcoholic fatty liver disease (NAFLD) is related to vitamin D and bone health in obese children is unknown. The aim of this study was to evaluate vitamin D status and bone mineral density (BMD) in obese children according to their condition within the NAFLD spectrum. Anthropometric data, laboratory tests, and abdominal ultrasonography were obtained from 94 obese children. The subjects were divided into three groups according to NAFLD spectrum: normal liver, simple steatosis, and nonalcoholic steatohepatitis (NASH). Although there were no differences in vitamin D levels between the three groups, these groups showed significant differences in highly sensitive C-reactive protein (P=0.044), homeostasis model assessment of insulin resistance (HOMA-IR) (P=0.02), hepatic fibrosis scores (P<0.05), and trunk fat percentage (P=0.025). Although there were significant differences in BMDs, the age-matched BMD z-scores were not significantly different between the three groups. Serum vitamin D levels were negatively correlated with age (r=-0.368, P=0.023), serum uric acid levels (r=-0.371, P=0.022), fibrosis 4 (FIB4) (r=-0.406, P=0.011), and HOMA-IR (r=-0.530, P=0.001) in obese children with NASH. Multiple regression analysis for vitamin D in the NASH group revealed age and HOMA-IR as significant factors. In conclusion, inflammatory markers, hepatic fibrosis scores, trunk fat, and insulin resistance may reflect the spectrum of NAFLD in obese children, whereas vitamin D levels and BMD may not. In patients with NASH, however, low serum vitamin D is associated with hepatic fibrosis and insulin resistance, but not with bone health status.
Adolescent ; Adult ; Body Composition ; *Bone Density ; C-Reactive Protein/metabolism ; Child ; Female ; Humans ; Insulin Resistance ; Liver/pathology ; Male ; Non-alcoholic Fatty Liver Disease/*blood/*complications/pathology ; Obesity/*blood/*complications ; Regression Analysis ; Uric Acid/blood ; Vitamin D/*analogs & derivatives/blood ; Young Adult

BACKGROUNDThe efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for immunoglobulin A nephropathy (IgAN) are unclear. This study was designed to evaluate the efficacy and safety of telmisartan combined with clopidogrel, leflunomide, or both drugs for IgAN.

METHODSIt is a multicenter, prospective, double-dummy randomized controlled trial. Primary IgAN patients were recruited in 13 renal units across Beijing, China, from July 2010 to June 2012. After a 4-week telmisartan (80 mg/d) wash-in, 400 patients continuing on 80 mg/d telmisartan were randomly assigned to additionally receive placebo (Group A), 50 mg/d clopidogrel (Group B), 20 mg/d leflunomide (Group C), or 50 mg/d clopidogrel and 20 mg/d leflunomide (Group D). The 24-week intervention was completed by 360 patients. The primary endpoint was change in 24-h proteinuria at 24 weeks. A linear mixed-effect model was used to analyze the changes at 4, 12, and 24 weeks. Generalized estimating equations were used to evaluate changes in hematuria grade. This trial was registered at the Chinese Clinical Trial Registry.

RESULTSThe effects of telmisartan combined with leflunomide on changes in proteinuria (0.36 [95% confidence interval (CI) 0.18-0.55] g/d, P < 0.001), in serum uric acid (76.96 [95% CI 57.44-96.49] μmol/L, P < 0.001), in serum creatinine (9.49 [95% CI 6.54-12.44] μmol/L, P < 0.001), and in estimated glomerular filtration rate (-6.72 [95% CI-9.46 to -3.98] ml·min-1·1.73 m-2, P < 0.001) were statistically significant, whereas they were not statistically significant on changes in systolic and diastolic blood pressure and weight (P > 0.05). Telmisartan combined with clopidogrel had no statistical effect on any outcome, and there was no interaction between the interventions. No obvious adverse reactions were observed.

CONCLUSIONSTelmisartan combined with leflunomide, not clopidogrel, is safe and effective for decreasing proteinuria in certain IgAN patients.

TRIAL REGISTRATIONchictr.org.cn, ChiCTR-TRC-10000776; http://www.chictr.org.cn/showproj.aspx?proj=8760.

Adolescent ; Adult ; Benzimidazoles ; adverse effects ; therapeutic use ; Benzoates ; adverse effects ; therapeutic use ; Blood Pressure ; drug effects ; China ; Creatinine ; blood ; Female ; Glomerular Filtration Rate ; drug effects ; Glomerulonephritis, IGA ; blood ; drug therapy ; Humans ; Isoxazoles ; adverse effects ; therapeutic use ; Kidney Function Tests ; Male ; Middle Aged ; Prospective Studies ; Ticlopidine ; adverse effects ; analogs & derivatives ; therapeutic use ; Treatment Outcome ; Uric Acid ; blood ; Young Adult

CYP1A2, CYP2D6 and N-acetyltransferase activities were estimated in 100 patients with bladder cancer and 84 control subjects from measurements of theophylline, metoprolol and isoniazid and their metabolites in urine, respectively. The frequency of occurrence of slow acetylators of isoniazid and poor metabolizers of metoprolol were 16.7% and 1.2% in the control group and 16.3% and 2.0% in the cancer patient group. These differences were not significant. The recovery ratio of 1-methyluric acid(1-MU) from theophylline was significantly higher in patients with bladder cancer than in control subjects(0.340 +/- 0.016 versus 0.260 +/- 0.020, p< 0.05). The 1-MU recovery ratio was a significant, independent risk factor among the metabolic capacities tested as shown by logistic regression analysis, controlling for N-acetylation of isoniazid, hydroxylation of metoprolol, age, sex, and smoking. We concluded that the capacity for 3-demethylation of theophylline, as a reflection of CYP1A2 activity, is significantly associated with increased risk of nonoccupational urinary bladder cancer.
Acetylation ; Adult ; Aged ; Amines/metabolism ; Bladder Neoplasms/enzymology/*epidemiology ; Carcinoma, Transitional Cell/enzymology/*epidemiology ; Case-Control Studies ; Cytochrome P-450 CYP1A2 ; Cytochrome P-450 CYP2D6 ; Cytochrome P-450 Enzyme System/metabolism/*urine ; Disease Susceptibility ; Enzyme Induction ; Female ; Human ; Isoniazid/*pharmacokinetics ; Korea/epidemiology ; Logistic Models ; Male ; Methylation ; Metoprolol/*pharmacokinetics ; Middle Age ; Mixed Function Oxygenases/metabolism ; Mixed Function Oxygenases/metabolism ; Oxidoreductases/*urine ; Smoking ; Support, Non-U.S. Gov't ; Theophylline/*pharmacokinetics ; Uric Acid/analogs & derivatives/urine