Based on the target occupancy mathematical model, the binding kinetic process of potential active ingredients of lowering uric acid in Chrysanthemum morifolium with xanthine oxidase(XOD) was evaluated. The potential active ingredients of lowering uric acid in Ch. morifolium were screened by UPLC-Q-Exactivems MS technology, reference substance identification and in vitro enzymatic kinetics experiments. The binding kinetic parameters of xanthine oxidase and potential inhibitor in Ch. morifolium were determined by surface plasma resonance(SPR). The verified mathematical model of the XOD target occupancy evaluated the kinetic binding process of inhibitors and xanthine oxidase in vivo. According to UPLC-Q-Exactive MS and reference substance identification, 39 potential uric acid-lowering active ingredients in Ch. morifolium extracts were identified and the inhibitory activities of 23 compounds were determined. Three potential xanthine oxidase inhibitors were screened, namely genistein, luteolin, and apigenin. whose IC_(50 )were 1.23, 1.47 and 1.59 μmol·L~(-1), respectively. And the binding rate constants(K_(on)) were 1.26×10~6, 5.23×10~5 and 6.36×10~5 mol·L~(-1)·s~(-1), respectively. The dissociation rate constants(K_(off)) were 10.93×10~(-2), 1.59×10~(-2), and 5.3×10~(-2 )s~(-1), respectively. After evaluation by different administration methods, the three selected compounds can perform rapid and sustained inhibition of xanthine oxidase in vivo under combined administration. This study comprehensively evaluated the target occupancy process of three effective components in different ways of administration in vivo by UPLC-MS, concentration-response method, SPR technology and xanthine oxidase target occupancy model, which would provide a new research idea and method for screening active ingredients in traditional Chinese medicine.
Chromatography, Liquid ; Chrysanthemum ; Flavonoids ; Kinetics ; Pharmaceutical Preparations ; Tandem Mass Spectrometry ; Xanthine Oxidase/metabolism*

OBJECTIVETo evaluate the antioxidant activities of different chemical constituents from Astragalus mongholicus Bunge and their protection against xanthine (XA)/xanthine oxidase (XO)-induced toxicity in PC12 cells.

METHODSThe compounds of Astragalus mongholicus Bunge were isolated by chromatography and the structures were elucidated on the basis of spectral data interpretation. Their antioxidant activities were detected by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities in a cell-free system. Meanwhile, the effects against XA/XO-induced toxicity were assessed using MTT assay in PC12 cells.

RESULTSTen principal constituents were isolated and identified as formononetin (I), ononin (II), calycosin (III), calycosin-7-O-beta-D-glucoside (IV), 9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (V), adenosine (VI), pinitol (VII), daucosterol (VIII), beta-sitoster (IX) and saccharose (X) from Astragalus mongholicus Bunge. The compounds I, III, and IV scavenged DPPH free radicals in vitro. Formononetin and calycosin were found to inhibit XA/XO-induced cell injury significantly, with an estimated EC50 of 50 ng/mL.

CONCLUSIONCompound II, VI, and VII are first reported in this plant. Calycosin exhibits the most potent antioxidant activity both in the cell-free system and in the cell system.

Animals ; Astragalus Plant ; chemistry ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Free Radical Scavengers ; chemistry ; pharmacology ; Free Radicals ; metabolism ; Isoflavones ; chemistry ; pharmacology ; PC12 Cells ; Rats ; Xanthine ; toxicity ; Xanthine Oxidase ; toxicity

OBJECTIVETo investigate the protection effects of electroacupuncture on injury of lipid peroxidation induced by liver ischemia in septic rats.

METHODSForty-eight male SD rats were subjected to sepsis induced by cecal ligation and puncture (CLP), and were randomly divided into a Sham operation group (group A), a CLP model group (group B), a CLP model plus electroacupuncture at "Zusanli" (ST 36) group (group C), a CLP model plus electroacupuncture at the shame acupoint (group D), a vagotomy plus CLP model group (group E) and CLP model plus electroacupuncture group after vagotomy (group F), 8 rats in each group. CLP was performed in group E and group F after the abdominal vagotomy. Bilateral "Zusanli"(ST 36) points and the shame acupoint were electroacupunctured (2 mA, 2/100 Hz) for 1 hour in group C, group F and group D, respectively. The hepatic blood flow (HBF) was detected by a laser-Doppler flowmetry at 6 h after CLP. The plasma activity of alanine aminotransferase (ALT) was also determined and specimens of liver were harvested for evaluation of malondialdehyde (MDA), xanthine oxidase (XOD) and assessment of the rate of water content.

RESULTSThe blood flow of the liver was (56.97 +/- 11.95) U in group C which was significantly lower than (80.12 +/- 19.57) U in group A but higher than (42.61 +/- 10.97) U in group B, (44.53 +/- 9.23) U in group D, (30.05 +/- 4.46) U in group E and (30.46 +/- 6.38) U in group F (all P < 0.05) 6 h after CLP. Meanwhile, the levels of MDA, XOD, ALT and the rates of water content in liver in group C were all significantly higher than those in group A, but lower than those in the other four groups (all P < 0.05). The levels of MDA, XOD, ALT and the rates of water content in liver in group E and group F were all significantly higher than those in group D (all P < 0.05), while the blood flow of the liver lower than that in group D (P < 0.05), and with no significant differences in all above measurements between group E and group F (all P > 0. 05).

CONCLUSIONElectroacupuncture at "Zusanli" (ST 36) can promote hepatic blood flow, inhibit lipid peroxidation and alleviate hepatic edema and dysfunction in septic rats, which might be related with the completeness of cranial nerve.

Alanine Transaminase ; blood ; Animals ; Electroacupuncture ; Lipid Peroxidation ; Liver Circulation ; Male ; Rats ; Rats, Sprague-Dawley ; Sepsis ; physiopathology ; therapy ; Xanthine Oxidase ; metabolism

Eight compounds,(R)-2-[5-(methoxycarbonyl)-4-methyl-6-oxo-3,6-dihydro-2H-pyran-2-yl]acetic acid(1),(3S,4R)-3,4-dihydro-3,4-epoxy-5-hydroxynaphthalen-1(2H)-one(2),(-)-mitorubrinol(3),(-)-mitorubrin(4),(±)-asperlone A(5), terreusinone(6), verrucisidinol(7) and cerebroside C(8) were isolated from the endophytic fungus Talaromyces purpurogenus by using various column chromatographic techniques. Their structures were identified by NMR, MS, CD and optical rotation. Compounds 1 and 2 were new compounds. Their anti-diabetic activities in vitro were evaluated, and compound 1 showed moderate inhibitory activity toward XOD at 10 μmol·L~(-1) with the inhibition rate of 69.9%.
Endophytes/chemistry* ; Hypoglycemic Agents/chemistry* ; Magnetic Resonance Spectroscopy ; Molecular Structure ; Secondary Metabolism ; Talaromyces/chemistry* ; Tylophora/microbiology* ; Xanthine Oxidase/antagonists & inhibitors*

AIMTo explore the role of ligustrazin on dynamic changes of lipid peroxidation in hepatic ischemia/reperfusion injury (HIRI) and its mechanism.

METHODSThe HIRI model was used. Twenty rabbits were randomly divided into control group (n = 10) and ligustrazin group (n = 10). The xanthine oxidase (XO) activity, superoxide dismutase (SOD) activity,malondialdehyde (MDA) content and glutamic pyruvic transaminase (GPT) activity in plasma were observed before ischemia and at ischemia 25 min, reperfusion 25 min, reperfusion 60 min and reperfusion 120 min.

RESULTSThe XO activity, SOD activity, MDA content and GPT activity of ligustrazin group, as compared with control group, showed significant differences (P < 0.05 or P < 0.01) at total time points of reperfusion.

CONCLUSIONLigustrazin has notable anti-lipid peroxidation effect on HIRI, which is due to its inhibiting the generation of oxygen free radicals and its strengthening scavenging of oxygen free radicals.

Alanine Transaminase ; metabolism ; Animals ; Female ; Lipid Peroxidation ; drug effects ; Liver ; drug effects ; metabolism ; Male ; Malondialdehyde ; blood ; Pyrazines ; pharmacology ; Rabbits ; Reperfusion Injury ; metabolism ; Superoxide Dismutase ; metabolism ; Xanthine Oxidase ; metabolism

The attenuating effect of daidzein (DAI) on oxidative toxicity induced by Aroclor 1254 (A1254) was investigated in mouse testicular cells. Cells were exposed to A1254 alone or with DAI. The oxidative damage was estimated by measuring malondialdehyde (MDA) formation, superoxide dismutase (SOD) activity and glutathione (GSH) content. Results show that A1254 induced a decrease of germ cell number, an elevation in thiobarbituric acid reactive substances (TBARS) but a decrease in SOD activity and GSH content. However, simultaneous supplementation with DAI decreased TBARS level and increased SOD activity and GSH content. Consequently, dietary DAI may restore the intracellular antioxidant system to attenuate the oxidative toxicity of A1254 in testicular cells.
Animals ; Chlorodiphenyl (54% Chlorine) ; toxicity ; Hypoxanthine ; toxicity ; Isoflavones ; pharmacology ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred ICR ; Oxidation-Reduction ; Testis ; drug effects ; metabolism ; Xanthine Oxidase ; toxicity

OBJECTIVETo explore the mischief mechanism of oxidative stress in the varicocele (VC).

METHODSSerum was taken from the spermatic and peripheral veins on ligation of the internal spermatic veins in 28 infertile males with VC. Experimental VC was established in male rats by partial ligation of the left renal vein. And testis tissue was taken three months after operation. The nitric oxide(NO), nitric oxide synthetase (NOS), xanthine oxidase (XO), lactic acid(Lac) and lactic dehydrogenase (LDH) in the serum of 28 infertile males with VC and the testis tissue of the VC rats were detected by spectrophotometry.

RESULTSNO, NOS, XO and Lac in the serum of internal spermatic veins in the infertile males with VC were significantly higher than in the serum of peripheral veins in the VC patients (P < 0.01, P < 0.05). LDH was lower than that in peripheral serum. NO and XO of the left testis tissue in the VC rats were higher compared with the control group (P < 0.01). Lac in the left testis of the VC rats was lower than that in the control group rats (P < 0.01).

CONCLUSIONNO, NOS and XO in the serum of the VC patients and in the testis tissues of the VC rats were increased, and Lac and LDH were changed obviously, which might not only disturb spermatogenesis, but also inhibit sperm motility. Therefore they might be one of the causes of infertility in VC patients.

Adult ; Animals ; Humans ; Infertility, Male ; etiology ; Male ; Nitric Oxide ; analysis ; Nitric Oxide Synthase ; analysis ; Oxidative Stress ; Rats ; Rats, Wistar ; Varicocele ; complications ; metabolism ; Xanthine Oxidase ; analysis

Animals ; Chronic Disease ; Febuxostat ; Heart Failure ; drug therapy ; metabolism ; Humans ; Reactive Oxygen Species ; Thiazoles ; pharmacology ; therapeutic use ; Xanthine Oxidase ; antagonists & inhibitors

Human xanthine oxidase is considered to be a target for therapy of hyperuricemia. Cichorium intybus is a Chinese plant medicine which widely used in Xinjiang against various diseases. In order to screen the inhibitors of xanthine oxidase from C. intybus and to explore main pharmacological actions of cichory a compound collection of C. intybus was built via consulting related references about chemical research on cichory. The three-dimensional crystal structure of xanthine oxidase (PDB code: 1N5X) from Protein Data Bank was downloaded.. Autodock 4.2 was employed to screen the inhibitors of xanthine oxidase from cichory 70 compounds were found to possess quite low binding free energy comparing with TEI (febuxostat). C. intybus contains constituents possessing potential inhibitive activity against xanthine oxidase. It can explain the main pharmacological actions of cichory which can significantly lower the level of serum uric acid.
Chicory ; chemistry ; Databases, Protein ; Drugs, Chinese Herbal ; chemistry ; Enzyme Inhibitors ; chemistry ; Humans ; Molecular Docking Simulation ; Molecular Structure ; Xanthine Oxidase ; antagonists & inhibitors ; metabolism

Hyperuricemic patients with gouty arthritis or tophi, a serum uric acid concentration of 8.0 mg/dL or higher, and complications should be treated with urate-lowering drugs. Conventionally, allopurinol is used to treat hyperuricemia and gout, but it is necessary to adjust the dosage according to the degree of renal impairment. Uncommonly, allopurinol may have severe or fatal side effects. The non-purine xanthine oxidase inhibitor febuxostat undergoes hepatic metabolism and may require less dose adjustment in association with renal function. It is considered to be an alternative treatment for hyperuricemic patients with chronic kidney disease. Our experience suggests that low-dose febuxostat is a promising alternative to allopurinol for the treatment of gouty arthritis or tophi in peritoneal dialysis patients.
Allopurinol ; Arthritis, Gouty ; Gout* ; Humans ; Hyperuricemia ; Kidney Failure, Chronic ; Metabolism ; Peritoneal Dialysis ; Peritoneal Dialysis, Continuous Ambulatory* ; Renal Insufficiency, Chronic ; Uric Acid ; Xanthine Oxidase ; Febuxostat